Chapter 1

Class Description
Figure 15.3
contain another zoom factor object, multiplying the effect of
the child zoom factor.
The top-level zoom factor, however, uses a
CGraphicsDevice (not another TZoomFactor).
In the example, the zoom factor uses the screen device. This is set up as follows in the hello
control constructor:
iZoomFactor.SetGraphicsDeviceMap(iCoeEnv->ScreenDevice());
iZoomFactor is used for getting the appropriate size and device- dependent font and size
for drawing.
The following section studies the device-independent drawing code in the
CExampleHelloView class and the small amount of device- independent code for
allocating a font in the CExampleHelloControl class. In the next section, we'll see how
the drawing code is used by the CExampleHelloControl class.
15.1.1 Device-independent Drawing
Device-independent drawing is largely conducted by the CExample-HelloView class.
Here is its declaration:
class CExampleHelloView : public CBase
{
public:
// Construct/destruct
static CExampleHelloView* NewL();
~CExampleHelloView();
// Settings
void SetTextL(const TDesC& aText);
void SetFullRedraw(TBool aFullRedraw);
// Draw