Location:
coeccntx.h
Link against: cone.lib
MCoeControlContext
Supported from 5.0
Interface to allow sharing of graphics settings between controls.
The interface provides functions to set the graphics context of a
control before drawing. If a control has its iContext
member set,
the UI Control Framework calls functions defined by this interface when a
control is about to be drawn. Developers must implement
PrepareContext()
, which is called by the framework, to initialise
the control’s window with the required graphics settings.
To use control contexts, a control should inherit from an
MCoeControlContext
-derived class. To share the context between
controls, this control should then be set as the context for all controls that
wish to share it. This is done by setting the iContext
member of
each of the controls — using
CCoeControl::SetControlContext()
and
CCoeControl::CopyControlContextFrom()
.
Defined in MCoeControlContext
:
ActivateContext()
, PrepareContext()
, ResetContext()
virtual void ActivateContext(CWindowGc& aGc,RDrawableWindow& aWindow) const;
Activates a graphics context for the specified window.
This function is called whenever a control is about to be
drawn. Its default implementation activates the graphics context given by
aGc
for the window given by aWindow
, and calls
PrepareContext()
.
This function may be overridden by derived classes.
|
virtual void PrepareContext(CWindowGc& aGc) const;
Initialises graphics context settings.
This function should be implemented by derived classes to
initialise the graphics context, given by aGc
, with the required
settings. The default implementation is empty.
|
virtual void ResetContext(CWindowGc& aGc) const;
Resets the control context.
The default implementation first resets the graphics context given
by aGc
, and then calls PrepareContext()
. The function
may be overridden by derived classes.
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