如何在 ImageViewZoom 中使用的位图上画线？

Question

我最近开始使用 ImageViewZoom (https://github.com/sephiroth74/ImageViewZoom) 而我要做的就是时不时地在这个视图中使用的位图上画一些线。

我试过按下面的方式进行，结果是View不能再缩放了

protected void onDraw(Canvas canvas) 
{   
    // TODO Auto-generated method stub
    super.onDraw(canvas);

    Canvas bmp_canvas = new Canvas(bmp);//bmp is the original bitmap

    Paint paint = new Paint();

    //Draw map
    paint. setColor(Color.BLUE);
    paint. setStrokeWidth(10);
    int i;
    for(i=0; i<toDraw.size();i++)
    {
        Segment now = toDraw.get(i); //toDraw is a List and stores the lines

        PointType tmp_start = now.s;
        PointType tmp_end = now.e;

        bmp_canvas.drawLine((float)tmp_start.x, (float)tmp_start.y, 
                (float)tmp_end.x, (float)tmp_end.y, paint);
    }

    Matrix matrix = getImageViewMatrix();
    setImageBitmap(bmp, matrix, ZOOM_INVALID, ZOOM_INVALID);        
    return;
}

那么正确的做法是什么呢？非常感谢！

Answer 1

嗯，我自己解决了！

我是按照以下方式做的：

public void drawMap(Bitmap bmp) //a new function outside of onDraw()
{
    Bitmap now_bmp = Bitmap.createBitmap(bmp);
    Canvas canvas = new Canvas(now_bmp);
    Paint paint = new Paint();

    //Draw map
    paint. setColor(Color.BLUE);
    paint. setStrokeWidth(10);
    int i;
    for(i=0; i<toDraw.size();i++)
    {
        Segment now = toDraw.get(i);

        PointType tmp_start = now.s;
        PointType tmp_end = now.e;

        canvas.drawLine((float)tmp_start.x, (float)tmp_start.y, 
                (float)tmp_end.x, (float)tmp_end.y, paint);
    }

    Matrix matrix = getDisplayMatrix();
    setImageBitmap(now_bmp, matrix, ZOOM_INVALID, ZOOM_INVALID);     
}

简单来说就是创建一个Canvas以原点为Bitmap，然后在上面画点东西，结果会存入位图中，并得到当前的矩阵，将新的位图设置到ImageViewZoom ，仅此而已。

如何在 ImageViewZoom 中使用的位图上画线？

How to draw lines on the bitmap used in ImageViewZoom?

android

bitmap

imageview