Android中Bitmap位圖的渲染與操作

１.通過一張資源文件得到一個位圖

Bitmap bmp =  BitmapFactory.decodeResource(this.getResources(),R.drawable.icon);

2.繪制位圖

canvas.drawBitmap(bmp,0,0,paint);

3.旋轉位圖

方法一：

canvas.save();

canvas.rotate(30,bmp.getWidth()/2,bmp.getHeight()/2);

canvas.drawBitmap(bmp,0,0,paint);

canvas.restore();

方法二：

Matrix mx = new Matrix();

mx.postRotate(30,bmp.getWidth()/2,bmp.getHeight()/2);

canvas.drawBitmap(bmp,0,0,paint);

4平移位圖

方法一：

canvas.save();

canvas.translate(10,10);

canvas.drawBitmap(bmp,0,0,paint);

canvas.restore();

方法二：

Matrix mx = new Matrix();

mx.postTranslate(10,10);

canvas.drawBitmap(bmp,0,0,paint);