×
Namespaces

Variants
Actions

Constructing a Symbian container control

From Nokia Developer Wiki
Jump to: navigation, search
Article Metadata
Code ExampleTested with
Devices(s): Nokia N95
Compatibility
Platform(s): S60 3rd Edition, FP1
S60 3rd Edition FP1
Article
Keywords: CCoeControl, TResourceReader, CCoeControlArray
Created: tepaa (07 Mar 2008)
Last edited: hamishwillee (30 May 2013)

Contents

Overview

This code snippet shows how to create a container control that owns custom controls. The example shows how to focus the first component with a rectangle and how to change focus.

The example extends the existing code snippet How to create a custom control in Symbian C++.

Container controls store their controls into CCoeControlArray.

Header

class CMyContainerControl : public CCoeControl
{
public:
static CMyContainerControl* NewL(const TRect& aRect);
static CMyContainerControl* NewLC(const TRect& aRect);
virtual ~CMyContainerControl();
 
private: // from CCoeControl
void Draw(const TRect& aRect) const;
void SizeChanged();
 
public: // own methods
// NOTE: Transfer ownership to CMyContainerControl
void AddControlL(CCoeControl* aControl,TInt aControlId);
void UpdateControls();
 
private: // own methods
CMyContainerControl();
void ConstructL(const TRect& aRect);
};


Source

CMyContainerControl* CMyContainerControl::NewL(const TRect& aRect)
{
CMyContainerControl* self = CMyContainerControl::NewLC(aRect);
CleanupStack::Pop(self);
return self;
}
 
CMyContainerControl* CMyContainerControl::NewLC(const TRect& aRect)
{
CMyContainerControl* self = new(ELeave) CMyContainerControl();
CleanupStack::PushL(self);
self->ConstructL(aRect);
return self;
}
 
CMyContainerControl::CMyContainerControl()
{
}
 
CMyContainerControl::~CMyContainerControl()
{
}
 
void CMyContainerControl::ConstructL(const TRect& aRect)
{
// No parent owner, so create an own window
CreateWindowL();
 
// Initialize component array
InitComponentArrayL();
 
SetRect(aRect);
 
ActivateL();
}
 
void CMyContainerControl::SizeChanged()
{
UpdateControls();
}
 
void CMyContainerControl::UpdateControls()
{
TPoint position;
 
// Goes through all components of this container control
CCoeControlArray::TCursor cursor = Components().Begin();
CCoeControl* ctrl = NULL;
while ((ctrl = cursor.Control<CCoeControl>()) != NULL)
{
// If control is not visible, do not set it's position
if (!ctrl->IsVisible())
{
cursor.Next();
continue;
}
 
// Set position
ctrl->SetPosition(position);
 
// Set size
TSize size = ctrl->MinimumSize();
size.SetSize(Rect().Width(),size.iHeight);
ctrl->SetSize(size);
 
// Calculate position
position.iY += size.iHeight;
 
// Does control fit to view?
if (position.iY >= Rect().iBr.iY)
{
ctrl->MakeVisible(EFalse);
}
else
{
ctrl->MakeVisible(ETrue);
}
 
cursor.Next();
}
}
 
void CMyContainerControl::Draw(const TRect& /*aRect*/) const
{
CWindowGc& gc = SystemGc();
gc.SetBrushColor(KRgbBlack);
gc.Clear(Rect());
}
 
void CMyContainerControl::AddControlL(CCoeControl* aControl,TInt aControlId)
{
// NOTE: Transfer ownership of CCoeControl to CMyContainerControl
// Add control into container control
Components().AppendLC(aControl,aControlId);
CleanupStack::Pop(aControl);
 
// Focus first component
if (Components().Count()==1)
{
aControl->SetFocus(ETrue);
}
 
// Update control's position
UpdateControls();
}

SizeChanged

When CMyContainerControl's size changes (when, for example, SetRect() is called), components' positions have to be calculated again.

void CMyContainerControl::SizeChanged()
{
// Sets new position of the components
UpdateControls();
}

Focusing component

Make the following changes to the CMyControl component.

  • CMyControl::Draw() must call DrawFocusFrame() for drawing the focus rectangle
  • CMyControl::DrawFocusFrame() is a new method where focus rectangle is drawn
void CMyControl::Draw(const TRect& aRect) const
{
CWindowGc& gc = SystemGc();
gc.SetBrushColor(KRgbBlue);
gc.Clear(Rect());
 
DrawFocusFrame(aRect);
}
 
void CMyControl::DrawFocusFrame(const TRect& aRect) const
{
// Nothing to draw if not focused
if ( IsFocused() == EFalse )
return;
 
// Prep for draw
CWindowGc& gc = SystemGc();
gc.SetPenStyle( CGraphicsContext::ESolidPen );
gc.SetPenSize( TSize(KFocusFrameWidth,KFocusFrameWidth) );
gc.SetBrushStyle( CGraphicsContext::ENullBrush );
gc.SetPenColor( KRgbDarkGray );
 
// Draw the rounded rectangle
gc.DrawRoundRect( aRect, TSize( KFrameRoundRadius, KFrameRoundRadius ) );
}

Postconditions

CMyContainerControl container has some CMyControlcustom controls in a list.

See also

Custom Control Series:

This page was last modified on 30 May 2013, at 04:37.
122 page views in the last 30 days.

Was this page helpful?

Your feedback about this content is important. Let us know what you think.

 

Thank you!

We appreciate your feedback.

×