Bitmap and DrawPoint

Bitmap and DrawPoint
Android UI 中有时需要画Bitmap，那么如何画Bitmap？

利用已有资源初始化Bitmap。

 public void fillPointArrays(int color,Drawable drawable) {        Bitmap bitmap = Bitmap.createBitmap(pointSize, pointSize, Bitmap.Config.ARGB_8888);        Canvas canvas = new Canvas(bitmap);        drawable.setBounds(0, 0, pointSize, pointSize);        drawable.draw(canvas);        pointArray[color] = bitmap;    } Resources r = this.getContext().getResources(); fillPointArrays(GREEN,r.getDrawable(R.drawable.green_point));

屏幕触摸画点，利用已经初始化的Bitmap画点。

@Overridepublic boolean onTouchEvent(MotionEvent event) {//获得触摸点的坐标point = newPoint(event.getX(), event.getY());refressCanvas();return true;}

onTouchEvent(MotionEvent event) 重载了View()的函数，用来监听屏幕的触摸，从event事件中可以获得触摸点的坐标。

根据触摸点的坐标，画出触摸的点。

    //画点    private void drawPoint(Canvas canvas){    canvas.drawBitmap(pointArray[0],point.x*pointSize+xOffset,point.y*pointSize+yOffset,paint);    }//根据触摸点坐标找到对应点private Point newPoint(Float x, Float y){Point p = new Point(0, 0);for (int i = 0; i < maxX; i++) {if ((i * pointSize + xOffset) <= x&& x < ((i + 1) * pointSize + xOffset)) {p.setX(i);}}for (int i = 0; i < maxY; i++) {if ((i * pointSize + yOffset) <= y&& y < ((i + 1) * pointSize + yOffset)) {p.setY(i);}}return p;}

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