1.點選圖片放大到全屏顯示

private void initImageView() {
    final WindowManager windowManager = getWindowManager();
    final RelativeLayout relativeLayout = new RelativeLayout(this);
WindowManager.LayoutParams layoutParams = new WindowManager.LayoutParams();
getScreenWidthAndHeight();
layoutParams.width = mScreenWidth
 
;
layoutParams.height = mScreenHeight;
//FLAG_LAYOUT_IN_SCREEN
layoutParams.flags = WindowManager.LayoutParams.FLAG_FULLSCREEN;
layoutParams.format = PixelFormat.RGBA_8888;//讓背景透明，放大過程可以看到當前介面
layoutParams.verticalMargin = 0;
windowManager.addView(relativeLayout,layoutParams);
    final PhotoView animationIV = new 
 
PhotoView(getContext());
animationIV.setScaleType(ImageView.ScaleType.FIT_CENTER);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.MATCH_PARENT);
relativeLayout.addView(animationIV,params);
relativeLayout.setFocusableInTouchMode(true
 
);
Picasso.with(getContext()).load(imageId).into(animationIV);
animationIV.setOnClickListener(new View.OnClickListener() {
        @Override
public void onClick(View v) {
            windowManager.removeView(relativeLayout);
}
    });
relativeLayout.setOnKeyListener(new View.OnKeyListener() {
        @Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
            if (keyCode == KeyEvent.KEYCODE_BACK) {
                if (null != windowManager && null != relativeLayout) {
                    windowManager.removeView(relativeLayout);
}
                return true;
}
            return false;
}
    });
}

2.PhotoView是繼承ImageView，實現是對圖片放大後可以區域性的拉伸放大，雙擊放大