Android 倒影实现算法

核心提示：public class MirrorView extends View {Paint m_paint;int m_nShadowH;Drawable m_dw;Bitmap m_bitmap;//xxxxMatrix mMatrix;int shadowHeight;public MirrorView(Context

public class MirrorView extends View {

Paint m_paint;

int m_nShadowH;

Drawable m_dw;

Bitmap m_bitmap;

//xxxx

Matrix mMatrix;

int shadowHeight;

public MirrorView(Context context, Bitmap bitmap) {

super(context);

m_bitmap = bitmap;

_Init();

// TODO Auto-generated constructor stub

}

private void _Init() {

//m_dw = new BitmapDrawable(BitmapFactory.decodeResource(getResources(), R.drawable.icon));

m_dw = new BitmapDrawable(m_bitmap);

m_dw.setBounds(0,0,m_dw.getIntrinsicWidth(),m_dw.getIntrinsicHeight());

m_nShadowH = m_dw.getIntrinsicHeight()/1;

m_paint = new Paint(Paint.ANTI_ALIAS_FLAG);

LinearGradient lg = new LinearGradient(0, 0, 0, m_nShadowH, 0xB0FFFFFF, 0x00000000, Shader.TileMode.CLAMP);

m_paint.setShader(lg);

m_paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.MULTIPLY));

//xxxx

mMatrix = new Matrix();

}

@Override

public void onDraw(Canvas canvas) {

super.onDraw(canvas);

int nX = 0;

int nY = 0;

_DrawNormalImg(canvas, nX, nY);

_DrawMirror(canvas, nX, nY);

}

private void _DrawNormalImg(Canvas canvas, int nX, int nY) {

canvas.save(Canvas.MATRIX_SAVE_FLAG);

canvas.translate(nX, nY);

m_dw.draw(canvas);

canvas.restore();

}

private void _DrawMirror(Canvas canvas, int nX, int nY) {

int nW = m_dw.getIntrinsicWidth();

int nH = m_dw.getIntrinsicHeight();

// U.dout("nW="+nW+",nH="+nH);

//xxxx

shadowHeight=nH/2;

//xxxx

float[] src={0, nH, nW, nH, nW,nH - m_nShadowH, 0, nH - m_nShadowH};

float[] dst={ 0, nH, nW, nH,nW, shadowHeight, 0, shadowHeight };