如何使用画布上设置位图图像onTouchEvent。 [英] How to set onTouchEvent on Bitmap image using canvas.

问题描述

我是在android开发新的。我想特别是对于图像设置onTouchEvent。这样我可以做一些工作，比如增加分数等...

i'm new in android development. I wanted to set onTouchEvent particularly for an image. so that i can do some work ,like increase score etc....

下面是示例code我尝试..

Here is the sample code i tried..

    @Override
protected void onDraw(Canvas canvas) 
{
          canvas.drawBitmap(image1, random.nextInt(455), random.nextInt(270), paint);
          canvas.drawText("SCORE = "+score, 10, 20, paint);
    }

     @Override
public boolean onTouchEvent(MotionEvent event) 
{
    // TODO Auto-generated method stub

    if(toggelFlag)
    {
        score = score+10;

    }

    return super.onTouchEvent(event);

}

其实我想增加得分一次我只触碰图像。但在这里，如果我的任何地方轻触屏幕的增加得分。我希望它仅用于图像。

Actually i wanted to increase the score once i touch the image only. But here if i touch anywhere in the screen its increase the score. I want it for image only.

推荐答案

创建与图像边界这样的区域对象：

Create a Region object with the image bounds like this:

Region region = new Region(left, top, right, bottom);

左，上，右，下定义图像范围。

left, top, right and bottom define the image bounds.

然后，当你处理触摸事件检查，如果区域包含事件的位置。将是：

Then, when you handle a touch event check if region contains the event position. Would be:

public boolean onTouchEvent(MotionEvent event)
{
    float x = event.getX();
    float y = event.getY();

    if(region.contains((int)x, (int)y))
    {
        // touch in image
    }

    return super.onTouchEvent(event);
}

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