#include <mw/coecntrl.h>
Link against: cone.lib
| class CCoeControl : public CBase, public MObjectProvider |
| Protected Attributes | |
|---|---|
| CCoeEnv * | iCoeEnv |
| MCoeControlContext * | iContext |
| TPoint | iPosition |
| TSize | iSize |
| Public Member Enumerations | |
|---|---|
| enum | TEventDataConfig { EEventDataAllowGroupedPointerEvents } |
| enum | TPrepareType { EPrepareProcess, EPrepareHandle } |
| enum | TZoomType { EAbsoluteZoom, ERelativeZoom } |
Control base class from which all other controls are derived.
| CCoeEnv * | iCoeEnv | [protected] |
| MCoeControlContext * | iContext | [protected] |
| TPoint | iPosition | [protected] |
| TSize | iSize | [protected] |
Contains flags for configuring event data.
| Enumerator | Value | Description |
|---|---|---|
| EEventDataAllowGroupedPointerEvents | 0x01 | Used for enabling grouped pointer events. |
There can be grouped and normal non-grouped events, which both need different kind of processing. These "preparation types" are used in common event handling code to tell what to do with the events once they are prepared for handling.
| Enumerator | Value | Description |
|---|---|---|
| EPrepareProcess | Events are being prepared for ProcessPointerEventL. | |
| EPrepareHandle | Events are being prepared for HandlePointerEventL. |
| Enumerator | Value | Description |
|---|---|---|
| EAbsoluteZoom | ||
| ERelativeZoom |
| IMPORT_C | CCoeControl | ( | ) |
Default C++ constructor.
Initialises the CCoeControl base class.
Note: CCoeControl is normally used as a base class from which concrete control classes are derived. However, it can also be instantiated as a concrete class.
| IMPORT_C | CCoeControl | ( | CCoeEnv * | aCoeEnv | ) |
C++ constructor.
Initialises the CCoeControl base class.
Note: CCoeControl is normally used as a base class from which concrete control classes are derived. However, it can also be instantiated as a concrete class.
| Parameters | |
|---|---|
| aCoeEnv | The control environment. |
| CCoeControl | ( | const CCoeControl & | aControl | ) | [protected, inline] |
| IMPORT_C | ~CCoeControl | ( | ) |
Destructor.
It destroys the window owned by the control, if it is a window-owning control.
In debug builds, this checks if the control still exists on the control stack and raises a CONE 44 panic if it is. An application must remove every control that it has added to the stack.
| IMPORT_C TZoomFactor | AccumulatedZoom | ( | ) | const |
Return the zoom factor for this control. Takes account of zoom factors in parent controls to calculate accumulated zoom factor.
| IMPORT_C void | ActivateGc | ( | ) | const [protected] |
Activates the standard graphics context.
This is the graphics context owned by the control environment (CCoeEnv).
Applications do not normally need to call this function, as it is called by the control framework whenever it is about to call Draw().
| IMPORT_C void | ActivateL | ( | ) | [virtual] |
Sets the control as ready to be drawn.
The application should call this function on all controls that are not components in a compound control.
The purpose of this function is that controls are not always ready to be drawn as soon as they have been constructed. For example, it may not be possible to set the control's extent during construction, but its extent should always be set before it is drawn. Similarly, if a control is to be made invisible, this should be done before it is activated.
The default implementation sets a flag in the control to indicate it is ready to be drawn. If the control is a compound control, the default implementation also calls ActivateL() for all the control's components. To get the control's components it uses CountComponentControls() and ComponentControl(), which should be implemented by the compound control.
ActivateL() is typically called from the control's ConstructL() function .
Notes:
This function can be overridden. This is useful for doing late initialisation of the control, using information that was not available at the time the control was created. For example, a text editor might override ActivateL() and use it to enquire whether it is focused: if it is, it makes the cursor and any highlighting visible. At the time when the editor is created, it doesn't know whether or not it has keyboard focus.
If overriding ActivateL(), the implementation must include a base call to CCoeControl's ActivateL().
| IMPORT_C RBackedUpWindow & | BackedUpWindow | ( | ) | const [protected] |
Gets the backed-up window owned by the control.
The window must be of type RBackedUpWindow. If you don't know whether the window is of type RWindow or RBackedUpWindow, you should use DrawableWindow().
Deprecated
| IMPORT_C const MCoeControlBackground * | Background | ( | ) | const |
Returns the background drawer object associated with this object, if any. Null is returned if there is no such object. Compare with FindBackground(), which looks up the parent chain to find a background drawer.
| IMPORT_C TBool | CapturesPointer | ( | ) | const [protected] |
Tests whether pointer capture is set for the control.
This returns true if SetPointerCapture() has been called with aCapture=ETrue.
| IMPORT_C void | ClaimPointerGrab | ( | TBool | aSendUpEvent = ETrue | ) |
Claims the pointer-grab from another control.
This ensures that all subsequent pointer events are delivered to it and not to the control that originally owned the grab.
The function allows a control to claim the pointer grab only if the pointer is already grabbed by another control.
This method is to be used in systems implementing single-pointer events. Or in systems implementing multiple-pointer events but where this control's window has single-pointer emulation enabled.
See also: RWindowBase::ClaimPointerGrab()
| Parameters | |
|---|---|
| aSendUpEvent | Passed as the argument to RWindowBase::ClaimPointerGrab(). |
Claims pointer grab from another control.
This ensures that all subsequent pointer events of the specified pointer are delivered to it and not to the control that originally owned the grab.
The function allows a control to claim the pointer grab only if the pointer is already grabbed by another control.
This method is intended to be called on a control who's window implements multi-pointer events. If called on a window without multiple pointers enabled, wserv will ignore the pointer number and grab the emulated pointer.
See also: RWindowBase::ClaimPointerGrab() RWindowBase::EnableMMultiplePointers()
| Parameters | |
|---|---|
| aPointerNumber | The number of the pointer for which to claim the grab. |
| aSendUpEvent | Passed as the argument to RWindowBase::ClaimPointerGrab(). |
| IMPORT_C void | CloseWindow | ( | ) | [protected] |
Closes the window owned by this control.
It is called from CCoeControl's destructor for window-owning controls.
| IMPORT_C TBool | ComponentArrayExists | ( | ) | const |
| IMPORT_C CCoeControl * | ComponentControl | ( | TInt | aIndex | ) | const [virtual] |
Gets an indexed component of a compound control.
There are 2 ways to implement a compound control. One way is to override this function. The other way is to use the CCoeControlArray functionality (see the InitComponentArrayL method).
Note: within a compound control, each component control is identified by an index, where the index depends on the order the controls were added: the first is given an index of 0, the next an index of 1, and so on.
| Parameters | |
|---|---|
| aIndex | The index of the control. |
| IMPORT_C CCoeControlArray & | Components | ( | ) | [protected] |
Returns a component array to store child controls.
This function is useful when the control is a compound control. The CCoeControlArray class provides functions to easily add and remove controls. The array must have been created before this function can be called. The InitComponentArrayL does this.
See also: CCoeControl::InitComponentArrayL()
| IMPORT_C const CCoeControlArray & | Components | ( | ) | const [protected] |
Returns a component array to store child controls.
This function is useful when the control is a compound control. The CCoeControlArray class provides functions to easily add and remove controls. The array must have been created before this function can be called. The InitComponentArrayL does this.
See also: CCoeControl::InitComponentArrayL()
Configures events, used e.g. for enabling grouped pointer events.
See also: TEventDataConfig for possible values.
| Parameters | |
|---|---|
| aEventDataConfig | The configuration flags, |
| IMPORT_C void | ConstructFromResourceL | ( | TResourceReader & | aReader | ) | [virtual] |
Constructs the control from a resource file.
This function has an empty default implementation. It should be implemented if the control is to be displayed within a dialog. It should initialise the control, reading in resource values from the resource file.
Note: if a control is not displayed in a dialog, it is necessary to set the control's associated window using SetContainerWindowL(). Since this may leave, the control should be constructed using ConstructL().
| IMPORT_C MCoeControlContext * | ControlContext | ( | ) | const |
Gets the control context being used by this control.
The function does not transfer ownership to the caller.
| CCoeEnv * | ControlEnv | ( | ) | const [inline] |
Gets the control environment object for this control.
| IMPORT_C void | CopyControlContextFrom | ( | const CCoeControl * | aControl | ) |
Sets the control's context from another control.
| Parameters | |
|---|---|
| aControl | The control whose context is copied. |
| IMPORT_C TInt | CountComponentControls | ( | ) | const [virtual] |
Gets the number of controls contained in a compound control.
There are 2 ways to implement a compound control. One way is to override this function. The other way is to use the CCoeControlArray functionality (see the InitComponentArrayL method).
| IMPORT_C void | CreateBackedUpWindowL | ( | RWindowTreeNode & | aParent | ) | [protected] |
Creates a control's window as a backed-up window.
The new window is the child of aParent and the display mode of the control becomes the same as that of aParent.
Deprecated
| Parameters | |
|---|---|
| aParent | The window to be the parent of this control's window. Does not have to be a backed-up window. |
| IMPORT_C void | CreateBackedUpWindowL | ( | RWindowTreeNode & | aParent, |
| TDisplayMode | aDisplayMode | |||
| ) | [protected] | |||
Creates a control's window as a backed-up window.
The new window is the child of aParent. Furthermore, the window's extent is set to that of the control.
The window will have the same display mode as the system display mode (the provided aDisplayMode is ignored).
Deprecated
| Parameters | |
|---|---|
| aParent | The window of the control to be the parent of this control. Does not have to be a backed-up window. |
| aDisplayMode | Ignored. The window will always be created with the system display mode. |
| IMPORT_C void | CreateWindowL | ( | ) | [protected] |
Creates a control's window.
The created window is the child of the application's window group.
This function makes the specified control a window-owning control, and would typically be called in the control's ConstructL() function.
Note:
The use of window owning controls is discouraged, as these tax run-time resources. Ideally only the top level control in an appUi would be window owning. There are some exceptions to this rule, e.g. floating controls like menus, dialogs and scroll bars.
| IMPORT_C void | CreateWindowL | ( | const CCoeControl * | aParent | ) | [protected] |
Creates a control's window, specifying the parent control.
The control's window is created as a child of the parent control's window.
This function makes the specified control a window-owning control, and would typically be called in the control's ConstructL() function.
Note:
The use of window owning controls is discouraged, as these tax run-time resources. Ideally only the top level control in an appUi would be window owning. There are some exceptions to this rule, e.g. floating controls like menus, dialogs and scroll bars.
In general, the overload with no parameters should be used.
| Parameters | |
|---|---|
| aParent | The control to be the parent of this control. |
| IMPORT_C void | CreateWindowL | ( | RWindowTreeNode & | aParent | ) | [protected] |
Creates a control's window, specifying its parent window and its extent.
This function makes the specified control a window-owning control, and would typically be called in the control's ConstructL() function. It also sets the window's extent to that of the control.
Note:
The use of window owning controls is discouraged, as these tax run-time resources. Ideally only the top level control in an appUi would be window owning. There are some exceptions to this rule, e.g. floating controls like menus, dialogs and scroll bars.
In general, the overload with no parameters should be used.
| Parameters | |
|---|---|
| aParent | The window of the control to be the parent of this control. |
| IMPORT_C void | CreateWindowL | ( | RWindowGroup * | aParent | ) | [protected] |
Creates a control's window, specifying its parent window group.
This function makes the specified control a window-owning control, and would typically be called in the control's ConstructL() function.
Note:
The use of window owning controls is discouraged, as these tax run-time resources. Ideally only the top level control in an appUi would be window owning. There are some exceptions to this rule, e.g. floating controls like menus, dialogs and scroll bars.
In general, the overload with no parameters should be used.
| Parameters | |
|---|---|
| aParent | The window group of the control to be the parent of this control |
| IMPORT_C CWindowGc * | CustomGc | ( | ) | const |
Returns the custom graphics context set for this control (if any). Note that unlike CCoeControl::SystemGc(), this function ignores the parent window's state and returns the context set explicitly for this control instance, or NULL if none has been set.
| IMPORT_C void | DeactivateGc | ( | ) | const [protected] |
Deactivates the standard graphics context owned by the UI control framework.
Applications do not normally need to call this function, as it is called by the control framework whenever it has called Draw() and drawing is completed.
| IMPORT_C void | DrawBackground | ( | const TRect & | aRect | ) | const |
Draws the control's background using its graphics context. Unlike DrawNow() and DrawDeferred(), this function does not propagate the draw to component controls.
| Parameters | |
|---|---|
| aRect | The area to be redrawn. This can be the control's entire rectangle, or a sub-rectangle within it. |
| IMPORT_C void | DrawDeferred | ( | ) | const |
Draws the control, with low priority.
This function is called by an application or other code.
It causes the control area to be marked as invalid, which will eventually cause a redraw initiated by the window server. The control framework handles redraw events at a lower priority than user input events, which means that any pending user input events will be processed before the redraw event. DrawDeferred() therefore allows a control to do drawing at a lower priority than drawing performed by DrawNow().
An advantage of using DrawDeferred() is that if you make multiple calls to DrawDeferred() on the same area of a control, the window server will not generate a redraw event to do drawing that has already been superceded. If you make multiple calls to DrawNow(), however, all of them get processed, even if they have already been superceded by the time they are processed.
| IMPORT_C void | DrawForeground | ( | const TRect & | aRect | ) | const |
Draws the control's foreground using the control's graphics context. Unlike DrawNow() and DrawDeferred(), this function does not propagate the draw to component controls.
| Parameters | |
|---|---|
| aRect | The area to be redrawn. This can be the control's entire rectangle, or a sub-rectangle within it. |
| IMPORT_C void | DrawNow | ( | ) | const |
Draws the entire control
This function is called by an application or other code. The application should call this function when the control is first created and is ready for drawing, or if a change in application data or the control's internal state means that entire control's appearance is no longer up-to-date.
Partial redrawing of a control is sometimes more appropriate than drawing the entire control, and in this case, use DrawNow(const TRect &aRect) instead.
DrawNow() is implemented by CCoeControl and MAY NOT be overridden. It calls Draw() on the control itself, and also on all its component controls, if it is a compound control. (To do this it uses CountComponentControls() and ComponentControl(), which should be implemented by the derived control class.) If the control is a window-owning control, it also calls Draw() for its child windows (if any).
| IMPORT_C void | DrawNow | ( | const TRect & | aRect | ) | const |
Draws the control, its components and child windows, within the bounds defined by the given rectangle.
| Parameters | |
|---|---|
| aRect | The rectangular region of the control to be drawn. |
| IMPORT_C RDrawableWindow * | DrawableWindow | ( | ) | const |
Gets the control's associated drawable window.
The control must be a window-owning control.
This function should be called if it is not known whether the window is of type RWindow or RBackedUpWindow. RDrawableWindow is an abstract base class from which RWindow and RBackedUpWindow are derived.
See also: Window()
| IMPORT_C void | EnableDragEvents | ( | ) | [protected] |
Requests pointer drag events.
This function should be called if a control is required to receive pointer drag and move events. The default behaviour for all controls is that pointer drag and move events are not delivered.
The control framework does not provide a function to disable drag events at a later time, but this can be done via the Window Server API, by calling Window()->PointerFilter().
Note:
By default, pointer move events are not delivered, even after calling EnableDragEvents(), because they are not normally required in a pen-based system. The window server can be configured to deliver pointer move events if required, e.g. for a mouse-based system.
See also: RWindowBase::PointerFilter()
| IMPORT_C void | EnableReportControlStateChange | ( | TBool | aState | ) |
Set the status of the report control state change.
See also: SetDimmed(), MakeVisible()
| Parameters | |
|---|---|
| aState | Set the state as Enable or Disable to control the report control state change. |
| IMPORT_C void | EnableWindowTransparency | ( | ) | [protected] |
By default, all windows are opaque. This means that semi-transparent drawing performed into the window will blend with other content of that window, but not with the content of the window(s) behind. This acts as an important performance optimization, limiting the amount of drawing needed to update the screen.
Call this method to allow semi-transparent drawing into the window to be blended with the content of the windows behind. (Because of the performance implications, be careful not to enable window transparency unless really required.)
This will set the window to use the alpha channel information of the drawing performed into it, and set the initialize window background to fully transparent (before any drawing is made into it).
Note that although the same effect can be achieved by calling the RWindow methods directly, calling this method instead will allow correct drawing of semi-transparent control backgrounds (see MCoeControlBackground).
This method must only be called on (non-BackedUp) window owning controls.
See also: MCoeControlBackground
| TInt | EventDataConfiguration | ( | ) | const |
| IMPORT_C const MCoeControlBackground * | FindBackground | ( | ) | const |
Return an MCoeControlBackground object, if there is one - looking up the parent chain as necessary. Compare to Background(), which does not go up the parent chain.
| IMPORT_C const CCoeFontProvider & | FindFontProvider | ( | ) | const |
Return the font provider used by this control
| IMPORT_C void | FocusChanged | ( | TDrawNow | aDrawNow | ) | [protected, virtual] |
Responds to a change in focus.
This is called whenever the control gains or loses focus, as a result of a call to SetFocus(). A typical use of FocusChanged() is to change the appearance of the control, for example by drawing a focus rectangle around it.
The default implementation is empty, and should be overridden by the CCoeControl-derived class.
| Parameters | |
|---|---|
| aDrawNow | Contains the value that was passed to it by SetFocus(). |
Gets the overridden physical colour.
This is the colour which has been mapped to the logical colour specified by a call to OverrideColorL(). If the logical colour specified has not been overridden, the aColor value is not changed.
| Parameters | |
|---|---|
| aLogicalColor | The logical colour for which the corresponding physical colour will be retrieved. The set of logical colours for a standard GUI application are defined in TLogicalColor. |
| aColor | On return, contains the physical colour which has been mapped to aLogicalColour by a call to OverrideColorL(). |
| IMPORT_C void | GetColorUseListL | ( | CArrayFix< TCoeColorUse > & | aColorUseList | ) | const [virtual] |
Gets the list of logical colours used to draw the control.
The list includes an explanation of how each colour is used. The default implementation is empty.
If overriding GetColorUseListL(), the implementation must include a base call to CCoeControl's GetColorUseListL().
| Parameters | |
|---|---|
| aColorUseList | The colour list. |
| IMPORT_C void | GetHelpContext | ( | TCoeHelpContext & | aContext | ) | const [virtual] |
Gets the control's help context.
The default implementation is empty. The function must be implemented in derived classes to associate the control with a particular Help file and topic in a context sensitive application. The implementation should set the public data members of TCoeHelpContext to the required Help file UID and context descriptor, as created using the Context-Sensitive Help Compiler.
| Parameters | |
|---|---|
| aContext | The control's help context |
| IMPORT_C CCoeControl * | GrabbingComponent | ( | ) | const [protected] |
Returns the component of this control which is grabbing the pointer in systems implementing a single pointer. Or in a multi-pointer system where single-pointer emulation is enabled on this control's window.
| IMPORT_C CCoeControl * | GrabbingComponent | ( | TInt | aPointer | ) | const [protected] |
Returns the component of this control which is grabbing the specified pointer. This method is to be used on controls who's window has multiple-pointer events enabled.
| IMPORT_C void | HandleComponentControlsResourceChange | ( | TInt | aType | ) | [protected] |
Handles a change to the resources in the components of a compound control.
See also: HandleResourceChange()
| Parameters | |
|---|---|
| aType | A message UID value. |
| IMPORT_C void | HandleControlArrayEventL | ( | CCoeControlArray::TEvent | aEvent, |
| const CCoeControlArray * | aArray, | |||
| CCoeControl * | aControl, | |||
| TInt | aControlId | |||
| ) | [protected, virtual] | |||
Handles events generated by the CCoeControlArray.
This function is useful when the control is a compound control and the CCoeControlArray functionality is used. The CCoeControlArray functions that add and remove controls will use this event handler to notify the control that child controls have been added or removed.
The default implementation of this function forwards the events to the layout manager (if there is one). If the event is EControlAdded it also sets the container window of the new child control unless the child control is a window owning control. If the event is EControlRemoved it also sets the parent of the removed child control to null.
| Parameters | |
|---|---|
| aEvent | The type of the event |
| aArray | The array that generated the event |
| aControl | The control affected by the event |
| aControlId | The id of the control affected by the event |
| IMPORT_C void | HandlePointerBufferReadyL | ( | ) | [protected, virtual] |
Handles pointer buffer ready events.
This function is called whenever the control receives an event of type EEventPointerBufferReady, unless one of its component controls has grabbed the pointer, in which case the function is called on that control. An event of type EEventPointerBufferReady will only be received if the pointer move buffer has been set up using window server functions.
The pointer move buffer is typically used when the application requires a continuous stream of pointer drag events, such as in a drawing application.
See also: RWindowBase::AllocPointerMoveBuffer()
| IMPORT_C void | HandlePointerEventL | ( | const TPointerEvent & | aPointerEvent | ) | [virtual] |
| IMPORT_C void | HandleRedrawEvent | ( | const TRect & | aRect | ) | const [protected] |
Handles redraw events.
In normal circumstances this function should not be used or overridden by the derived control class.
| Parameters | |
|---|---|
| aRect | The rectangle to be redrawn. |
| IMPORT_C void | HandleResourceChange | ( | TInt | aType | ) | [virtual] |
Handles a change to the control's resources.
The types of resources handled are those which are shared across the environment, e.g. colours or fonts. For colour scheme changes, DrawDeferred() is called in order to redraw the control.
If overriding HandleResourceChange(), the implementation must include a base call to CCoeControl's HandleResourceChange().
See also: HandleComponentControlsResourceChange()
| Parameters | |
|---|---|
| aType | A message UID value. |
| IMPORT_C TBool | HasBorder | ( | ) | const [virtual] |
Tests if the control has a border.
When component controls are arranged in a container, the container control may need to know whether or not the components have borders, as this may affect the way the components are laid out within the container.
The default implementation of this function returns EFalse, but can be overridden to provide the required functionality.
| IMPORT_C const MCoeControlHitTest * | HitTest | ( | ) | const |
Gets the object that defines the hit region inside the control's rectangle. The object is set by calling SetHitTest().
| IMPORT_C void | IgnoreEventsUntilNextPointerUp | ( | ) |
Sets the control to ignore pointer events until the next pointer up.
This means that all events until and including the next pointer up event are discarded and are not processed.
This can be used for example if the user presses the Esc key while selecting text by dragging the pointer device to ensure that further dragging does not result in continued selection.
| IMPORT_C TInt | Index | ( | const CCoeControl * | aControl | ) | const |
Gets the index of a control that is a component of this control.
| Parameters | |
|---|---|
| aControl | The component control. |
| IMPORT_C void | InitComponentArrayL | ( | ) | [protected] |
Creates a component array to store child controls.
This function is useful when the control is a compound control. It creates an array where the child controls can be stored. The CCoeControl::Components return the created array. The CCoeControlArray class provides functions to easily add and remove controls.
| IMPORT_C TCoeInputCapabilities | InputCapabilities | ( | ) | const [virtual] |
Gets the control's input capabilities.
Classes that override CCoeControl::OfferKeyEventL() should also override this function, returning a TCoeInputCapabilities object whose attributes correspond to the behaviour of the OfferKeyEventL() function. The default implementation returns TCoeInputCapabilities::ENone.
It is not necessary to call InputCapabilities() on any component controls from inside a class's InputCapabilities() function. This is done automatically by the UI Control Framework.
| IMPORT_C TBool | IsActivated | ( | ) | const [protected] |
Tests if the control has been activated.
A control is not ready to draw until it is activated.
| IMPORT_C TBool | IsBackedUp | ( | ) | const |
Tests if the window owned by the control is a backed-up window.
Deprecated
| IMPORT_C TBool | IsBeingDestroyed | ( | ) | const [protected] |
Tests if the control is being destroyed.
| IMPORT_C TBool | IsBlank | ( | ) | const [protected] |
| IMPORT_C TBool | IsDimmed | ( | ) | const |
Tests if the control is dimmed.
This function returns the value of a flag within the control which is set and unset using SetDimmed().
| IMPORT_C TBool | IsFocused | ( | ) | const |
| IMPORT_C TBool | IsNonFocusing | ( | ) | const |
| IMPORT_C TBool | IsReadyToDraw | ( | ) | const [protected] |
Tests if the control is ready for drawing.
This returns true if the control has been activated and is visible.
| IMPORT_C TBool | IsSemiTransparent | ( | ) | const [protected] |
Checks whether semitransparency has been enabled for this control.
See also: EnableWindowTransparency()
| IMPORT_C TBool | IsVisible | ( | ) | const |
Tests if the control is visible.
Unless MakeVisible() has been called with argument EFalse, the control is visible.
| IMPORT_C MCoeLayoutManager * | LayoutManager | ( | ) | const |
Gets the layout manager
| IMPORT_C void | MakeVisible | ( | TBool | aVisible | ) | [virtual] |
Sets this control as visible or invisible.
This causes the control to disappear or reappear. When a control is created, it is made visible by default.
MakeVisible() can be called before or after the control is activated.
Notes:
This function may be overridden.
The visibility of the control can be queried using IsVisible().
If MakeVisible() is used to make a component visible, and the control captures the pointer (see CapturesPointer()), MakeVisible() throws away any pending pointer events for that control.
Typical uses are for scrollbars, or for dialogs where some user responses are not required in certain circumstances.
| Parameters | |
|---|---|
| aVisible | ETrue to make the control visible, EFalse to make it invisible. |
| IMPORT_C TInt | MaximumWidth | ( | ) | const |
Gets the control's maximum width
| IMPORT_C TSize | MinimumSize | ( | ) | [virtual] |
Sets the control's minimum required size.
This function should be overridden by the concrete control class if the control is to be displayed inside a dialog. Standard GUI dialogs set the size and position of their components automatically, and use this function to enquire the minimum size that a control requires.
Other container controls that automatically calculate the layout of their components may also use this function.
| IMPORT_C TTypeUid::Ptr | MopSupplyObject | ( | TTypeUid | aId | ) | [protected, virtual] |
Reimplemented from MObjectProvider::MopSupplyObject(TTypeUid)
Retrieves an object of the same type as that encapsulated in aId.
This function is used to allow controls to ask their owners for access to other objects that they own.
Other than in the case where NULL is returned, the object returned must be of the same object type - that is, the ETypeId member of the object pointed to by the pointer returned by this function must be equal to the iUid member of aId.
| Parameters | |
|---|---|
| aId | An encapsulated object type ID. |
| void | NotifyFontChange | ( | const CCoeFontProvider * | aFontProvider | ) |
Notify controls that the font has changed
| IMPORT_C MCoeControlObserver * | Observer | ( | ) | const |
Gets the control's observer.
| IMPORT_C TKeyResponse | OfferKeyEventL | ( | const TKeyEvent & | aKeyEvent, |
| TEventCode | aType | |||
| ) | [virtual] | |||
Handles key events.
If a control wishes to process key events, it should implement this function. The implementation must ensure that the function returns EKeyWasNotConsumed if it does not do anything in response to a key event, otherwise, other controls or dialogs may be prevented from receiving the key event. If it is able to process the event it should return EKeyWasConsumed.
When a key event occurs, the control framework calls this function for each control on the control stack, until one of them can process the key event (and returns EKeyWasConsumed).
Each keyboard key press results in three separate events: EEventKeyDown, EEventKey, and EEventKeyUp, in that order.
To receive key events, which can be processed by this function, the application should call CCoeAppUi::AddToStackL() to add the control to the stack. This only applies, however, to controls which are not components of a compound control. Compound controls should pass key events to their components as necessary: the components themselves do not go on the stack.
Classes that override CCoeControl::OfferKeyEventL() should also override the InputCapabilities() virtual function, returning a TCoeInputCapabilities object whose attributes correspond to the behaviour of the OfferKeyEventL() function. Note that it is not necessary to call InputCapabilities() on any component controls from inside a class' InputCapabilities() function. This is done automatically by the UI Control Framework.
If overriding OfferKeyEventL(), the implementation must include a base call to CCoeControl's OfferKeyEventL().
| Parameters | |
|---|---|
| aKeyEvent | The key event. |
| aType | The type of key event: EEventKey, EEventKeyUp or EEventKeyDown. |
Overrides the control's colour setting, as specified in the application's colour scheme.
This function does not change the application's colour scheme. It changes the colour mapping used in this control only.
See also: GetColor()
| Parameters | |
|---|---|
| aLogicalColor | The logical colour. Indicates which part of a control the physical colour maps to. The set of logical colours for a standard application are defined in TLogicalColor. |
| aColor | The new physical colour to which the logical colour should be mapped. |
| IMPORT_C TBool | OwnsWindow | ( | ) | const |
Tests if the control is window-owning.
| IMPORT_C CCoeControl * | Parent | ( | ) |
| IMPORT_C const CCoeControl * | Parent | ( | ) | const |
| IMPORT_C TPoint | Position | ( | ) | const |
Gets the control's position.
| IMPORT_C void | PositionChanged | ( | ) | [protected, virtual] |
Responds to changes in the position of a control.
It has an empty default implementation which may be overridden by the CCoeControl-derived class.
This function is called whenever the application calls SetPosition() on the control.
| IMPORT_C TPoint | PositionRelativeToScreen | ( | ) | const |
Gets the control's position relative to screen origin.
The screen origin is its top-left corner.
| IMPORT_C void | PrepareForFocusGainL | ( | ) | [virtual] |
Prepares the control for gaining focus.
Implementations may by taking any action required, such as updating control information. The default implementation is empty.
| IMPORT_C void | PrepareForFocusLossL | ( | ) | [virtual] |
Prepares the control for loss of focus.
A control which is displayed within a dialog should implement this function if it wishes to validate data entered into the control.
This function is called by the dialog framework immediately before it removes keyboard focus from a control within a dialog. It is intended to be used for validating the state of the control: for example, if the control allows the user to enter a date, PrepareForFocusLossL() would normally check to make sure the user did not enter an invalid date such as February 31st. If an invalid state is detected, PrepareForFocusLossL() should leave and issue a message to the user if appropriate. If it does leave, the framework does not perform the action that would have resulted in the control losing focus, and focus remains with the control to allow valid data to be entered.
In standard GUI dialogs, various actions can result in a control losing focus, for instance if the user presses the OK button or the Enter key to close the dialog and enter the information, or if the user navigates away from the focussed control. These actions result in PrepareForFocusLossL() being called on the control that currently has keyboard focus.
The default implementation of this function is empty, and it is not called from within the UI control framework. The function exists only to provide an interface to the control, for the GUI and any other UI library.
| void | ProcessPointerBufferReadyL | ( | ) |
| void | ProcessPointerEventL | ( | const TPointerEvent & | aPointerEvent | ) |
| IMPORT_C TRect | Rect | ( | ) | const |
Gets the control's extent.
The position of the top-left of the rectangle is (0,0) if the control owns its window. Otherwise, its position is relative to its window.
| void | RecursivelyMergeInputCapabilities | ( | TCoeInputCapabilities & | aInputCapabilities | ) | const |
Gets the input capabilities of the control and all its components.
| IMPORT_C TCoeInputCapabilities | RecursivelyMergedInputCapabilities | ( | ) | const |
Gets the input capabilities of the control and all its components.
| void | RefetchPixelMappingL | ( | ) |
Force all CCoeFontProviders to update their logical-to-pixel mapping from CCoeControlStaticSettings
| void | RemoveFromParent | ( | ) |
| IMPORT_C void | ReportEventL | ( | MCoeControlObserver::TCoeEvent | aEvent | ) | [protected] |
Sends an event to the control's observer (if the control has one).
| Parameters | |
|---|---|
| aEvent | The event type. |
| IMPORT_C TBool | RequestRelayout | ( | const CCoeControl * | aChildControl | ) | [virtual] |
Requests a relayout
The default implementation is to call the parents RequestRelayout().
TBool CAnyControl::RequestRelayout(const CCoeControl* aChildControl)
{
if(iRelayoutInProgress) return EFalse;
iRelayoutInProgress = ETrue;
//perform the relayout
iRelayoutInProgress = EFalse;
return ETrue;
}
When the request is addressed the requesting control knows that its SizeChanged() will be called.
| Parameters | |
|---|---|
| aChildControl | The child control that requests the relayout, might be NULL |
| IMPORT_C void | ResetGc | ( | ) | const [protected] |
Resets the standard graphics context.
The function resets the graphics context owned by the control environment to its default settings.
Returns the closest matching font from the control's current font provider to the requested logical font, taking into account the control's zoom factor.
This function should be used in preference to legacy functions like CEikonEnv::LegendFont(), CCoeEnv::NormalFont() or CCoeEnv::CreateScreenFontL().
Example 1: Instead of the control using a CFont class member, or calling NormalFont(), LegendFont() etc, it is recommended the control (e.g. in its Draw() method) call the new ScreenFont() method to temporarily access a CFont object owned by the font provider. This is a lot more efficient than repeatedly e.g. calling GetNearestFontInPixels(), and allows the CFont object used for text drawing to vary depending on the current zoom factor. Thus the CFont reference must not be kept as class member data, as it may be changed by the font provider at any time.
CSomeControl::Draw(const TRect& aRect)
{
XCoeTextDrawer textDrawer(TextDrawer());
textDrawer.SetAlignment(EHCenterVCenter);
textDrawer.DrawText(gc, iText, aRect, ScreenFont(TCoeFont::LegendFont());
}
Example 2: Although efficiently implemented, try not to call ScreenFont() or CCoeFontProvider::Font() repeatedly unnecessarily. Instead, create and use a local const CFont& on the stack, as shown below.
Note that the ScreenFont() call above is provided as short-hand for the code on the first two lines below. Also note that font providers and zoom factors apply hieratically to the control tree (i.e. setting the zoom factor or font provider on a container control affects the child controls too).
CSomeControl::Draw(const TRect& aRect)
{
const CCoeFontProvider& fontProvider = FindFontProvider();
const CFont& font = fontProvider.Font(TCoeFont::LegendFont(), AccumulatedZoom());
XCoeTextDrawer textDrawer(TextDrawer());
textDrawer.SetAlignment(EHCenterVCenter);
textDrawer.DrawText(gc, iText, aRect, font);
textDrawer.DrawText(gc, iText2, aRect, font);
}
See also: CCoeFontProvider TCoeFont
| Parameters | |
|---|---|
| aFont | Logical font to use. |
| IMPORT_C void | SetAdjacent | ( | TInt | aAdjacent | ) | [virtual] |
Sets the control's appearance when it is next to other controls.
Its intended use is to remove the double border that may occur if two controls, both with borders, are adjacent within a container control.
This function has an empty default implementation, and is not used within the UI control framework. However, it may be implemented and used by derived control classes.
| Parameters | |
|---|---|
| aAdjacent | Typically a value defined in TGulAdjacent. |
| IMPORT_C void | SetAllowStrayPointers | ( | ) | [protected] |
Sets whether or not to allow stray pointer events.
This function sets a flag that affects the way the control framework handles pointer events. By default, the flag is not set, and the control will ignore any pointer drag events and up events where the matching pointer down event occurred in a different control. This would happen if a user pressed the pointer down in a control, but then dragged the pointer into a different control before releasing it.
SetAllowStrayPointers() is typically used for menus, where stray pointer events are required because it is the pointer up event that is used to activate a menu option even when the pointer down event occured in a different menu pane. This is not the case in some other components such as command buttons, where a pointer down event and up event in succession are required to activate the button.
| IMPORT_C void | SetBackground | ( | const MCoeControlBackground * | aBackground | ) |
Sets a pointer to a MCoeControlBackground object that is responsible for drawing the control's background
See also: CCoeControl::EnableWindowTransparency()
| Parameters | |
|---|---|
| aBackground | Pointer to an object that implements MCoeControlBackground |
| IMPORT_C void | SetBlank | ( | ) | [protected] |
Sets a flag to indicate that the control is blank.
Once set, this flag cannot be unset for the lifetime of the control.
See also: IsBlank()
| IMPORT_C void | SetCanDrawOutsideRect | ( | ) | [protected] |
Allows the control to draw outside its own extent.
When a compound control is drawn, all its component controls are also drawn. However, unless this flag is set, they are not drawn if the rectangle they inhabit on the screen doesn't intersect with the rectangle to be drawn.
Setting this flag has the effect of allowing a component control to draw outside its own extent. It should be used with caution! By default, this flag is not set.
| IMPORT_C void | SetComponentsToInheritVisibility | ( | TBool | aInherit = ETrue | ) |
Sets the control's components to inherit the visibility setting of their container control.
If set, when MakeVisible() is called on the compound control, the visibility setting is propagated to all its components.
| Parameters | |
|---|---|
| aInherit | If ETrue, the control's components inherit its visibility setting; if EFalse they do not. |
| IMPORT_C void | SetContainerWindowL | ( | const CCoeControl & | aContainer | ) | [virtual] |
Sets the control's containing window by copying it from aContainer.
It also copies the control context from aContainer if one has not previously been set.
This function can only be called on non-window-owning (or 'lodger') controls.
If overriding SetContainerWindowL(), the implementation must include a base call to CCoeControl's SetContainerWindowL().
| Parameters | |
|---|---|
| aContainer | The compound control that is the container for this control. |
| IMPORT_C void | SetContainerWindowL | ( | RWindow & | aWindow | ) |
Sets the control's containing window, without transferring ownership of the window to this control.
This function can only be called on non-window-owning ('lodger') controls.
Note: the container's window can be accessed using Window(), DrawableWindow(), or BackedUpWindow().
| Parameters | |
|---|---|
| aWindow | The window owned by the container control. |
| IMPORT_C void | SetContainerWindowL | ( | RBackedUpWindow & | aWindow | ) |
Sets the control's containing window without transferring ownership of the window to this control.
The function can only be called on non-window-owning ('lodger') controls.
Note: the container's window can be accessed using Window(), DrawableWindow(), or BackedUpWindow().
Deprecated
| Parameters | |
|---|---|
| aWindow | The backed up window owned by the container control. |
| IMPORT_C void | SetControlContext | ( | MCoeControlContext * | aContext | ) |
Set the control context for this control.
| Parameters | |
|---|---|
| aContext | The context for this control. |
| IMPORT_C void | SetCornerAndSize | ( | TGulAlignment | aCorner, |
| const TSize & | aSize | |||
| ) | [protected] | |||
Sets the control's alignment and size.
The control's position is calculated, relative to the screen, according to the requested alignment.
Note: calling this function results in a call to SizeChanged().
| Parameters | |
|---|---|
| aCorner | The alignment of the control. |
| aSize | The control's size. |
Sets the control's custom graphics context. This value overrides the system context for this control and any children.
If aGraphicsContext is null, the control's graphics context is reset to the one it inherited from its parent, or to the default system graphics context (iCoeEnv->SystemGc()) if none of its parents have set their own graphics context.
This value is retrieved by CCoeControl::SystemGc().
| IMPORT_C void | SetDimmed | ( | TBool | aDimmed | ) | [virtual] |
Sets the control to be dimmed.
This function sets a flag within the control which indicates whether or not the control is dimmed (greyed out). This is typically used to show that the control is temporarily unavailable.
SetDimmed() does not initiate a redraw of the control. The application should call DrawNow() or DrawDeferred() if a redraw is required after calling SetDimmed(). The control's Draw() function should draw the control appropriately according to whether it is dimmed or not. (This can be enquired using IsDimmed().)
If overriding SetDimmed(), the implementation must include a base call to CCoeControl's SetDimmed().
| Parameters | |
|---|---|
| aDimmed | ETrue to dim the control, EFalse to set the control as not dimmed. |
Sets the control's extent, specifying a size and a position.
Note: calling this function results in a call to SizeChanged().
| Parameters | |
|---|---|
| aPosition | The position of the control, relative to its associated window. |
| aSize | The size of the control, in pixels. |
| IMPORT_C void | SetExtentToWholeScreen | ( | ) |
Sets the control's extent to the whole screen.
Note: calling this function results in a call to SizeChanged().
Sets this control to have the keyboard focus.
It sets the value of a focus flag within the control to the value given by aFocus. This flag indicates whether or not the control has keyboard focus, and its value can be enquired using IsFocused(). It then calls FocusChanged(), passing it the value given by aDrawNow, unless the control is invisible or not activated, in which case it passes ENoDrawNow.
Note that setting focus does not initiate a redraw. The control's implementation of FocusChanged() should do this if required. The control's Draw() function, or that of its container, should normally change the appearance of the control to indicate whether or not it currently has focus.
| Parameters | |
|---|---|
| aFocus | ETrue sets the control as having keyboard focus, EFalse sets it as not having keyboard focus. |
| aDrawNow | Flag to pass to FocusChanged(). |
| IMPORT_C void | SetFocusing | ( | TBool | aFocusing | ) |
Sets the control as able to receive keyboard focus.
| Parameters | |
|---|---|
| aFocusing | ETrue if the control can have focus, EFalse if it can't. |
| IMPORT_C void | SetFontProviderL | ( | const CCoeFontProvider & | aFontProvider | ) |
Set the font provider. This is an external object that takes the responsibililty for finding an appropriate font away from the control.
| Parameters | |
|---|---|
| aFontProvider | The provider to use. |
Deprecated. See DeprecatedCCoeControl::SetCustomGc().
| IMPORT_C void | SetGloballyCapturing | ( | TBool | aGlobal | ) |
Sets the global pointer capture flag.
This flag indicates whether or not pointer capture should be global.
The flag is used by SetPointerCapture() to determine what value to pass to RWindowBase::SetPointerCapture(). The default for the global capture flag, when a control is created, is EFalse.
| Parameters | |
|---|---|
| aGlobal | Value for global capture flag. |
| IMPORT_C TInt | SetHitTest | ( | const MCoeControlHitTest * | aHitTestControl | ) |
Installs a hit tester for this control. The tester defines the hit region, which is the area within the control that accepts pointer events. If no hit region is set, pointer events are accepted in the control's entire rectangle.
| Parameters | |
|---|---|
| aHitTestControl | Object which defines the hit region. |
| IMPORT_C void | SetLayoutManagerL | ( | MCoeLayoutManager * | aLayout | ) | [virtual] |
Sets the layout manager
If the control already has a layout manager, its MCoeLayoutManager::Detatch() is called. MCoeLayoutManager::Attach() is called on aLayout
The control doesn't take ownership of the Layout manager.
See also: MCoeLayoutManager::Attach
| Parameters | |
|---|---|
| aLayout | The new layout manager, NULL if you just want to remove the current layout manager. |
| IMPORT_C void | SetMopParent | ( | MObjectProvider * | aParent | ) |
Sets the context - that is, the enclosing parent control - for this control. If setting aParent as MopParent of this control creates a cyclic relationship, this method will do nothing.
| Parameters | |
|---|---|
| aParent | The parent object which is the context for the control. |
| IMPORT_C void | SetNeighbor | ( | CCoeControl * | aNeighbor | ) | [virtual] |
Sets an associated control.
This can be used to establish co-ordinated groups of controls for instance in dialogs without specific application co-operation.
This function has an empty default implementation, and is not used within the UI control framework. However, it may be implemented and used by derived control classes.
| Parameters | |
|---|---|
| aNeighbor | A control to be used by this function. |
| IMPORT_C void | SetNonFocusing | ( | ) |
Deprecated. Use SetFocusing().
Sets the control as unable to receive keyboard focus. The function would typically be called during construction of the control.
| IMPORT_C void | SetObserver | ( | MCoeControlObserver * | aObserver | ) |
Sets the control's observer.
| Parameters | |
|---|---|
| aObserver | The observer. |
| IMPORT_C TInt | SetParent | ( | CCoeControl * | aParent | ) | [virtual] |
Sets aParent as the parent of this control. If setting aParent as parent of this control will create a cyclic relationship, this method does nothing.
| Parameters | |
|---|---|
| aParent | The control to set as this control's parent. |
| IMPORT_C void | SetPointerCapture | ( | TBool | aCapture = ETrue | ) |
Sets pointer capture.
Once set, pointer capture lasts until SetPointerCapture() is called on the control with aCapture=EFalse.
This function is typically used by dialogs, to discard any pointer events that occur outside of the dialog.
See also: RWindowBase::SetPointerCapture()
| Parameters | |
|---|---|
| aCapture | If ETrue, passes the following value as the argument to RWindowBase::SetPointerCapture(): RWindowBase::TCaptureFlagAllGroups|RWindowBase::TCaptureFlagEnabled, if the control's global capture flag is set to ETrue (see SetGloballyCapturing()) or RWindowBase::TCaptureFlagEnabled if the control's global capture flag is set to EFalse. If EFalse, passes EFalse as the argument to RWindowBase::SetPointerCapture(). |
| IMPORT_C void | SetPosition | ( | const TPoint & | aPosition | ) |
Sets the control's position.
If the control owns its containing window, it achieves this by setting the position of the window. Otherwise, the position of the control is set relative to its containing window. The positions of the control's components are adjusted accordingly and PositionChanged() is called.
| Parameters | |
|---|---|
| aPosition | The position of the the top-left of the control, relative to its associated window. |
| IMPORT_C void | SetRect | ( | const TRect & | aRect | ) |
Sets the control's extent, specifying a rectangle.
Note: calling this function results in a call to SizeChanged().
| Parameters | |
|---|---|
| aRect | The rectangle that defines the control's extent. The rectangle's origin is relative to the origin of its associated window. |
| IMPORT_C void | SetSize | ( | const TSize & | aSize | ) |
Sets the control's size.
If the size, but not the position, of a control is set, then its position will default to TPoint(0,0).
Note: calling this function results in a call to SizeChanged().
| Parameters | |
|---|---|
| aSize | The control's size, in pixels. |
| IMPORT_C void | SetSizeWithoutNotification | ( | const TSize & | aSize | ) | [protected] |
Sets a control's size without calling SizeChanged().
If the size, but not the position, of a control is set, then its position will default to TPoint(0,0).
See also: SetSize()
| Parameters | |
|---|---|
| aSize | The control's size, in pixels. |
| IMPORT_C void | SetTextBaselineSpacing | ( | TInt | aSpacing | ) | [virtual] |
Sets the spacing between text baselines.
The default implementation calls SetTextBaselineSpacing of the layout manager if one is installed. It does nothing if there is no layout manager.
Derived classes that don't want to use the layout manager and still want to do something when the this function is called should re-implement it.
| Parameters | |
|---|---|
| aSpacing | The baseline spacing i.e. the space in pixels between the text baselines. |
Sets a Unique Handle (identifier). That the number is unique is the perogative of the caller!
See also: UniqueHandle()
| IMPORT_C void | SizeChanged | ( | ) | [protected, virtual] |
Responds to changes to the size and position of the contents of this control.
For a simple control this might include text or graphics. For a compound control it sets the size and position of the components.
The function is called whenever SetExtent(), SetSize(), SetRect(), SetCornerAndSize(), or SetExtentToWholeScreen() are called on the control. Note that the window server does not generate size-changed events: SizeChanged() gets called only as a result of calling the functions listed above. Therefore, if a resize of one control affects the size of other controls, it is up to the application to ensure that it handles the re-sizing of all affected controls.
| IMPORT_C CWindowGc & | SystemGc | ( | ) | const |
Gets the graphics context that is used when drawing the control.
This function walks the CCoeControl hierarchy upwards from child to parent until a context is found. If no control in the hierarchy has defined its own graphics context, the default system graphics context (iCoeEnv->SystemGc()) is returned.
All drawing is carried out through a graphics context. A graphics context must be activated before it can be drawn to, and deactivated when it is no longer needed. When drawing is done using Draw(), DrawNow() or DrawDeferred(), the application does not have to do this, as it is done within the control framework. However, for application-initiated drawing which is not done using DrawNow() or DrawDeferred(), the application should activate and deactivate the graphics context using ActivateGc() and DeactivateGc() (or CWindowGc::Activate() and CWindowGc::Deactivate()).
Gets the offset to the first text baseline relative to the top of the control.
The default implementation calls CalcTextBaselineOffset of the layout manager if one is installed. It returns 0 if no layout manager is installed.
Derived classes that don't want to use the layout manager and still want to return a baseline offset should re-implement this function.
| IMPORT_C CCoeTextDrawerBase & | TextDrawer | ( | TInt | aKey = KErrNotFound | ) | const [protected] |
Gets the text drawer to be used for the control. This method returns a reference simply because the return value must never be NULL. The ownership transfer rules of the returned CCoeTextDrawerBase object obey specific rules. If the CCoeTextDrawerBase::IsReusable() flag is set then the caller must call Reset when the object is not needed anymore else it should simply delete the object. The XCoeTextDrawer class is a wrapper around the CCoeTextDrawerBase that will implement this logic automatically. The method will start with the default text drawer. It then allows the childs background control to change the text drawer if the child itself is window owning. Otherwise only the parent control can change the text drawer.
| Parameters | |
|---|---|
| aKey | This parameter can be used by clients that need some custom behaviour. The framework doesn't use this parameter. |
| IMPORT_C RWindow & | Window | ( | ) | const [protected] |
Gets the control's associated window.
The control must be window owning, and the window must be of type RWindow. If you don't know whether the window is of type RWindow or RBackedUpWindow, you should use DrawableWindow().
| IMPORT_C void | WriteInternalStateL | ( | RWriteStream & | aWriteStream | ) | const [protected, virtual] |
| void | WriteInternalStateNowL | ( | RWriteStream & | aWriteStream | ) | const |
| IMPORT_C const TCoeZoomWithType * | ZoomWithType | ( | ) | const |
Return the zoom factor but without taking into account the zoom factor of the parent. Use of AccumulatedZoom() is recommended as it takes into account the zoom factor of the parent.
| CCoeControl & | operator= | ( | const CCoeControl & | aControl | ) | [protected, inline] |