newsrolltext.cpp

Symbian工程 九宫格界面

#include "NewsRollText.h"

#define SCROLL_INTERVAL 20000

CNewsRollText::CNewsRollText()
:iNewsBackgroundColor(KRgbWhite)
{
}
CNewsRollText::~CNewsRollText()
{
	if(iNewsText)	
	{
		delete iNewsText;
		iNewsText = NULL;
	}
	iNewsPeriodicTimer->Cancel();
	if(iNewsPeriodicTimer)	
	{
		delete iNewsPeriodicTimer;
		iNewsPeriodicTimer = NULL;
	}
}
//*//*/设置文本内容
void CNewsRollText::NewsSetTextL(const TDesC& aText)
{
	if(iNewsText)	
	{
		delete iNewsText;
		iNewsText = NULL;
	}
	iNewsText = aText.AllocL();
	CEikLabel::SetTextL(aText);
}
//实现文本滚动
TBool CNewsRollText::IsNeedScroll()
{
	if(iNewsText==NULL)
		return EFalse;
	if(iNewsStarPoint.iX > -iNewsLabelSize.iWidth)
		return ETrue;
	return EFalse;
}

void CNewsRollText::Start()
{
	if(iNewsPeriodicTimer==NULL && IsNeedScroll())
	{
		iNewsPeriodicTimer = CPeriodic::NewL(EPriorityNormal);
		iNewsPeriodicTimer->Start(0,SCROLL_INTERVAL,TCallBack(Tick,this));
	}
}

TInt CNewsRollText::Tick(TAny* p)
{
	CNewsRollText* pThis = (CNewsRollText*)p;
	pThis->DoScroll();
	return 0;
}

void CNewsRollText::DoScroll()
{
	//切割
	if(IsNeedScroll())
	{
		iNewsStarPoint.iX -= 2;
	}
	else
	{
		//重置
		iNewsStarPoint.iX = Rect().Size().iWidth;
	}
	CEikLabel::SetExtent(iNewsStarPoint, iNewsLabelSize);
	DrawDeferred();
}
//绘制控件背景
void CNewsRollText::Draw(const TRect& aRect) const
{
	CWindowGc& gc = SystemGc();

	gc.SetPenStyle( CGraphicsContext::ENullPen );
	gc.SetBrushStyle( CGraphicsContext::ESolidBrush );
	gc.SetBrushColor( iNewsBackgroundColor);
	gc.DrawRect( aRect );
	gc.SetBrushStyle( CGraphicsContext::ENullBrush );
	CEikLabel::Draw(aRect);
}

void CNewsRollText::NewsSetBackgroundColor(TRgb aColor)
{
	iNewsBackgroundColor = aColor;
}
void CNewsRollText::NewsSetExtent(const TPoint &aPosition, const TSize &aSize)
{
	iNewsStarPoint = aPosition;
	iNewsLabelSize = aSize;
	CEikLabel::SetExtent(iNewsStarPoint, iNewsLabelSize);
}