Bitmap透明度

public class helloWorld extends Activity {

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView( new drawCanvas(this) );

}

class drawCanvas extends View {

public drawCanvas(Context context) {

super(context);

}

@Override

protected void onDraw(Canvas canvas) {

super.onDraw(canvas);

// 取得Resource 圖片的Bitmap

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

// 建立Paint 物件

Paint vPaint = new Paint();

vPaint .setStyle( Paint.Style.STROKE ); //空心

vPaint .setAlpha( 75 ); // Bitmap透明度(0 ~ 100)

canvas.drawBitmap ( vBitmap , 50, 100, null ); //無透明

canvas.drawBitmap ( vBitmap , 50, 200, vPaint ); //有透明

}

}

}