废话不多说先粘贴代码  下边这段代码是在按钮的点击事件里面写的:

// 开启图片的缓存功能
mGuidePager.setDrawingCacheEnabled(true);
// 设置图片的质量
mGuidePager.setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH);
// 获取Bitmap
Bitmap drawingCache = mGuidePager.getDrawingCache();
// 获取上边的一半赋值给上边的ImageView
Bitmap topBitmap = getTopBitmap(drawingCache);
mTopImg.setImageBitmap(topBitmap);
                
// 获取下边的一半赋值给下边的ImageView
Bitmap bottomBitmap = getBottomBitmap(drawingCache);
mBottomImg.setImageBitmap(bottomBitmap);
// 开启动画
startAnim();

接下来是获取上下两部分的截图的代码 是本次事例的关键所在:

private Bitmap getTopBitmap(Bitmap drawingCache) {
        int height = drawingCache.getHeight() / 2;
        int width = drawingCache.getWidth();
        
        Bitmap.Config config = drawingCache.getConfig();
        Bitmap topBitmap = Bitmap.createBitmap(width, height, config);
        Canvas canvas = new Canvas(topBitmap);
        Matrix matrix = new Matrix();
        Paint paint = new Paint();
        //将图赋值到画布上
        canvas.drawBitmap(drawingCache, matrix, paint);
        return topBitmap;
    }
private Bitmap getBottomBitmap(Bitmap drawingCache) {
        int height = drawingCache.getHeight() / 2;
        int width = drawingCache.getWidth();
        Bitmap.Config config = drawingCache.getConfig();
        Bitmap bottomBitmap = Bitmap.createBitmap(width, height, config);
        
        Canvas canvas = new Canvas(bottomBitmap);
        Matrix matrix = new Matrix();
        //原图向上移动宽度的一半  让下边的一半可以画到画布上
        matrix.setTranslate(0, -height);
        Paint paint = new Paint();
        canvas.drawBitmap(drawingCache, matrix, paint);
        return bottomBitmap;
    }

再接下来是动画的代码  小意思了:

private void startAnim() {
        mGuidePager.setVisibility(View.INVISIBLE);
        mAllAnim.setVisibility(View.VISIBLE);
        //添加动画到集合中
        AnimationSet as1 = new AnimationSet(false);
        TranslateAnimation translateAnimation = new TranslateAnimation(0, 0, 0, -mTopImg.getHeight());
        AlphaAnimation alphaAnimation = new AlphaAnimation(1.0f, 0.0f);
        as1.addAnimation(translateAnimation);
        as1.addAnimation(alphaAnimation);
        as1.setDuration(1000);
        mTopImg.startAnimation(as1);
        
        TranslateAnimation translateAnimation1 = new TranslateAnimation(0, 0, 0, mBottomImg.getHeight());
        AlphaAnimation alphaAnimation1 = new AlphaAnimation(1.0f, 0.0f);
        AnimationSet animationSet = new AnimationSet(false);
        animationSet.addAnimation(translateAnimation1);
        animationSet.addAnimation(alphaAnimation1);
        animationSet.setDuration(1000);
        mBottomImg.setAnimation(animationSet);
        
    }

总结一下:

在这里给大家讲一下实现原理: 首先我们应该找到要获取截图的控件  我的事例中找的是一个ViewPager  他们的父布局最好是FrameLayout或者RelativeLayout 然后创建一个LinearLauout布局 覆盖在要获取截图的控件上方  然后在这个布局中添加两个ImageView,接下来在代码中将获取的两部分的截图分别赋值给这两个ImageView 并且分别为他俩添加动画即可。具体实现参见代码。

posted on 2017-11-08 14:26  从前有個人  阅读(144)  评论(0编辑  收藏  举报