If the button has a frame,
change its features by setting new frame IDs using the method SetFrameAndCenterIds() in the class CAknButton.
Use the flag KAknButtonStateHasLatchedFrame for
a button state to set whether the frame for the button in the state in question
should look latched down.
To disable the frame for the button, use
the KAknButtonNoFrame flag.
By default, the button text is truncated
to fit the size of the button. Use the KAknButtonSizeFitText flag
to make the method MinimumSize() return the size into which the text fits. To change the font, color,
and alignment of the text, use the following methods in CAknButton:
If you use an icon in your button, you can use the same icon for both the pressed and non-pressed states; however, for the dimmed state another icon is recommended. For the icon's appearance, follow the S60 look and feel guidelines. Dimmed icons are generated automatically if they are not provided by the application.
To change the scale mode for the
icon image, use the method CAnkButton::SetIconScaleMode(). By default, the button component
uses the EAspectRatioNotPreserved mode, so that the icon
fits the size of the button. To adjust the icon’s alignment on the button,
use the methods CAknButton::SetIconHorizontalAlignment() and CAknButton::SetIconVerticalAlignment().
If the button provides a help text,
it is shown close to the button if the button is focused or the stylus is
held down for some time. You can set the state-specific help text when constructing
the button, at the construction of a button state, or by calling CAknButtonState::SetHelpTextL(). To set the help
text for a dimmed button, use the method CAknButton::SetDimmedHelpTextL().
To change
time-outs for the help text, use the method CAknButton::SetHelpNoteTimeouts().
To display
and hide the button help text, use the methods ShowHelpL() and HideHelp() in the class CAknButton.
CAknButton supports
a background composed of both a CCoeControl background interface
and an Avkon skin background. If both are set, the CCoeControl-based
background has higher priority. In case of CCoeControl-based
background, do the following in order for the button’s background to be drawn
by the container:
Set the container class to be derived from the MCoeControlBackground interface.
Provide implementation for the Draw() method in the MCoeControlBackground interface.
Call the SetBackground( pointerToContainer ) method
for the button.
If the background is set from the skin, use the method CAknButton::SetBackGroundIds().
For implementation examples, see the sample code below:
// Text alignment top-left corner CGraphicsContext::TTextAlign horAlignment( CGraphicsContext::ELeft ); CAknButton::TAlignment verAlignment( CAknButton::ETop ); textButton->SetTextHorizontalAlignment( horAlignment ); textButton->SetTextVerticalAlignment( verAlignment ); // Preserve icon button aspect ratio iconButton->SetIconScaleMode( EAspectRatioPreserved ); // Help texts HBufC* helpText = StringLoader::LoadLC( R_MYAPP_HELPTEXT ); HBufC* dimmedHelpText = StringLoader::LoadLC( R_MYAPP_DIM_HELPTEXT ); // Set help text to current state textButton->State()->SetHelpTextL( *helpText ); // Set dimmed help text to all states textButton->SetDimmedHelpTextL( *dimmedHelpText ); CleanupStack::PopAndDestroy( 2 ); // helpText, dimmedHelpText // Help note timeout adjustments const TInt KButtonTimeoutBeforeNote = 300; const TInt KButtonTimeoutNoteInView = 5000; textButton->SetHelpNoteTimeouts( KButtonTimeoutBeforeNote, KButtonTimeoutNoteInView );