Why can't I draw a bitmap ?

[uponline]

Hi there !
When I write these code in my project ,but it never paint a bitmap , I don't know what's happend , tell me how to do it , please .

-------------
IMAppView.h
-------------
CFbsBitmap* iBitmap;                                 




---------------
IMAppView.cpp
---------------
void CIMAppView::ConstructL(const TRect& aRect)      
	{                                             
	CreateWindowL();                              
	LoadBitmapL();                                
	SetRect(aRect);                               
	ActivateL();                                  
	}                                             

void CIMAppView::LoadBitmapL()                       
	{                                             
	iBitmap=new (ELeave)CFbsBitmap();             
	_LIT(KMBMFILE,"\\system\\apps\\IM\\IM.mbm");  
	TFileName file(KMBMFILE);                     
	User::LeaveIfError(CompleteWithAppPath(file));
	                                              
	TRAPD(err,iBitmap->Load(file,EMbmImFace);)    
	User::LeaveIfError(err);                       
	                                              
	}                                             

void CIMAppView::Draw(const TRect& /*aRect*/) const  
	{                                             
	// Get the standard graphics context          
	CWindowGc& gc = SystemGc();                   
                                                     
	// Gets the control's extent                  
	TRect drawRect(Rect());                       
                                                     
	// Clears the screen                          
	gc.Clear(drawRect);                           
	gc.BitBlt(TPoint(20,20), iBitmap);            
	                                              
	}

[stenlik]

Hi,

your code looks correct.

1/So what really happens? Application runs and you see only white screen?

2/The CIMAppView is derived form the CCoeControl, isn't it?

3/How do you create CIMAppView - can you show us the code?

4/ When you debug the code - id the Draw() method called?

5/ What are aRect values in the ConstructL() method?

BR
STeN

[uponline]

/*
 ============================================================================
 Name		: IMAppView.h
 Author	  : 王秉先
 Copyright   : CartoonSMS
 Description : Declares view class for application.
 ============================================================================
 */

#ifndef __IMAPPVIEW_h__
#define __IMAPPVIEW_h__

// INCLUDES
#include <coecntrl.h>

// CLASS DECLARATION
class CFbsBitmap;
class CIMAppView : public CCoeControl
	{
public:
	// New methods

	/**
	 * NewL.
	 * Two-phased constructor.
	 * Create a CIMAppView object, which will draw itself to aRect.
	 * @param aRect The rectangle this view will be drawn to.
	 * @return a pointer to the created instance of CIMAppView.
	 */
	static CIMAppView* NewL(const TRect& aRect);

	/**
	 * NewLC.
	 * Two-phased constructor.
	 * Create a CIMAppView object, which will draw itself
	 * to aRect.
	 * @param aRect Rectangle this view will be drawn to.
	 * @return A pointer to the created instance of CIMAppView.
	 */
	static CIMAppView* NewLC(const TRect& aRect);

	/**
	 * ~CIMAppView
	 * Virtual Destructor.
	 */
	virtual ~CIMAppView();

public:
	// Functions from base classes

	/**
	 * From CCoeControl, Draw
	 * Draw this CIMAppView to the screen.
	 * @param aRect the rectangle of this view that needs updating
	 */
	void Draw(const TRect& aRect) const;

	/**
	 * From CoeControl, SizeChanged.
	 * Called by framework when the view size is changed.
	 */
	virtual void SizeChanged();

	/**
	 * From CoeControl, HandlePointerEventL.
	 * Called by framework when a pointer touch event occurs.
	 * Note: although this method is compatible with earlier SDKs, 
	 * it will not be called in SDKs without Touch support.
	 * @param aPointerEvent the information about this event
	 */
	virtual void HandlePointerEventL(const TPointerEvent& aPointerEvent);
	void LoadBitmapL();
private:
	// Constructors

	/**
	 * ConstructL
	 * 2nd phase constructor.
	 * Perform the second phase construction of a
	 * CIMAppView object.
	 * @param aRect The rectangle this view will be drawn to.
	 */
	void ConstructL(const TRect& aRect);

	/**
	 * CIMAppView.
	 * C++ default constructor.
	 */
	CIMAppView();
	CFbsBitmap* iBitmap;

	};

#endif // __IMAPPVIEW_h__
// End of File




/*
 ============================================================================
 Name	     : IMAppView.cpp
 Author	     : 王秉先
 Copyright   : CartoonSMS
 Description : Application view implementation
 ============================================================================
 */

// INCLUDE FILES
#include <coemain.h>
#include <aknutils.h>
#include <IM.mbg>
#include "IMAppView.h"

// ============================ MEMBER FUNCTIONS ===============================

// -----------------------------------------------------------------------------
// CIMAppView::NewL()
// Two-phased constructor.
// -----------------------------------------------------------------------------
//
CIMAppView* CIMAppView::NewL(const TRect& aRect)
	{
	CIMAppView* self = CIMAppView::NewLC(aRect);
	CleanupStack::Pop(self);
	return self;
	}

// -----------------------------------------------------------------------------
// CIMAppView::NewLC()
// Two-phased constructor.
// -----------------------------------------------------------------------------
//
CIMAppView* CIMAppView::NewLC(const TRect& aRect)
	{
	CIMAppView* self = new (ELeave) CIMAppView;
	CleanupStack::PushL(self);
	self->ConstructL(aRect);
	return self;
	}

// -----------------------------------------------------------------------------
// CIMAppView::ConstructL()
// Symbian 2nd phase constructor can leave.
// -----------------------------------------------------------------------------
//
void CIMAppView::ConstructL(const TRect& aRect)
	{
	// Create a window for this application view
	CreateWindowL();
	LoadBitmapL();
	// Set the windows size
	SetRect(aRect);

	// Activate the window, which makes it ready to be drawn
	ActivateL();
	}

void CIMAppView::LoadBitmapL()
	{
	iBitmap=new (ELeave)CFbsBitmap();
	 _LIT(KMBMFILE,"\\system\\apps\\IM\\IM.mbm");
	
	 TFileName file(KMBMFILE);
	// TFilename fname = _L("Multi.mbm");
	 
	 User::LeaveIfError(CompleteWithAppPath(file));
	 
	 TRAPD(err,iBitmap->Load(file,EMbmImFace);)
	 //User::LeaveIfError(iBitmap->Load(file,EMbmImFace));
	 
	 User::LeaveIfError(err);
	 
	}


// -----------------------------------------------------------------------------
// CIMAppView::CIMAppView()
// C++ default constructor can NOT contain any code, that might leave.
// -----------------------------------------------------------------------------
//
CIMAppView::CIMAppView()
	{
	// No implementation required
	}

// -----------------------------------------------------------------------------
// CIMAppView::~CIMAppView()
// Destructor.
// -----------------------------------------------------------------------------
//
CIMAppView::~CIMAppView()
	{
	// No implementation required
	}

// -----------------------------------------------------------------------------
// CIMAppView::Draw()
// Draws the display.
// -----------------------------------------------------------------------------
//
void CIMAppView::Draw(const TRect& /*aRect*/) const
	{
	// Get the standard graphics context
	CWindowGc& gc = SystemGc();

	// Gets the control's extent
	TRect drawRect(Rect());

	// Clears the screen
	gc.Clear(drawRect);
	gc.BitBlt(TPoint(20,20), iBitmap);
	
	}

// -----------------------------------------------------------------------------
// CIMAppView::SizeChanged()
// Called by framework when the view size is changed.
// -----------------------------------------------------------------------------
//
void CIMAppView::SizeChanged()
	{
	DrawNow();
	}

// -----------------------------------------------------------------------------
// CIMAppView::HandlePointerEventL()
// Called by framework to handle pointer touch events.
// Note: although this method is compatible with earlier SDKs, 
// it will not be called in SDKs without Touch support.
// -----------------------------------------------------------------------------
//
void CIMAppView::HandlePointerEventL(const TPointerEvent& aPointerEvent)
	{

	// Call base class HandlePointerEventL()
	CCoeControl::HandlePointerEventL(aPointerEvent);
	}

// End of File

[uponline]

when I run it , it's white screen, I used wizard of Carbide.C++ and never change kernel code ,

Hi,

your code looks correct.

1/So what really happens? Application runs and you see only white screen?

2/The CIMAppView is derived form the CCoeControl, isn't it?

3/How do you create CIMAppView - can you show us the code?

4/ When you debug the code - id the Draw() method called?

5/ What are aRect values in the ConstructL() method?

BR
STeN

[wizard_hu_]

Does the file \system\apps\IM\IM.mbm exist? Your current code expects it to be in epoc32\release\winscw\udeb\z\system\apps\IM\IM.mbm when you execute it in the emulator.
Note that TRAPD does not do anything with methods which do not leave. And Load is not LoadL, so it does not leave. Instead it returns an error code, so you could rather

TInt err=iBitmap->Load(file,EMbmImFace);

then you will probably get a -1, which you can decode via checking http://wiki.forum.nokia.com/index.php/Error_codes

[moshing]

I'm no expert, but I know that phones like .png's

[niyaz.khan]

hi,

Did u checked the applcation with giving full source mbm path.
Also try with removing DrawNow() from SizeChanged() function.

[uponline]

I'v done . Thanks guys.

_LIT(KMBMFILE,"\\system\\apps\\IM\\IM.mbm");

I changed this,and it's run .

_LIT(KMBMFILE,"\\resource\\apps\\IM.mbm");

[stenlik]

Ohh yes - I overlook the Load() bug...

BR
STeN