通过WindowManager图片切换的效果

最近为这个事情焦头烂额，原因无他。原来打算是把ViewPager放在WindowManager中，再设定一个定时器，让图片自动切换，但是搞了很久，发现无论如何，这个图片只显示一张。虽然日志看得出来图片确实在切换，但是除了这初始化的这张图片之外，其他的都是黑窗口，也就是没有显示出来。

 

此路不通，另找出路。其实未必用得着PagerAdapter。安卓就是这点方便，反正View，不管咋整，都是可以往窗口里面放的，我对界面不懂，所以这里也说不出个所以然来。但是这种需求，估计也是有的（比如有些比较恶心的广告程序，就是想要独占最上层，那用windowManager就是比较合适的方式）。

 

废话不多说，直接上代码

public class MainActivity extends Activity {
private Runnable viewpagerRunnable;
private Handler MainThreadhandler;
private WindowManager mWndMgr;
private ViewPager mViewPager;
private ImageView mImgView;
private WindowManager.LayoutParams mLayoutParams;
private Context mContext;
private List<ImageView> mImgViewList;
private int[] picRes = {R.drawable.first,R.drawable.second,R.drawable.third};
int CurrentIndex = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mContext = this.getApplicationContext();
MainThreadhandler = new Handler();
prepareImageView();
initView();
startAutomaticRoll();
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}

private void prepareImageView(){
mViewPager = new ViewPager(mContext);
mWndMgr = (WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics outMetrics = new DisplayMetrics();
mWndMgr.getDefaultDisplay().getMetrics(outMetrics);
mLayoutParams = new WindowManager.LayoutParams();
mLayoutParams.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
mLayoutParams.width = outMetrics.widthPixels;
mLayoutParams.height = outMetrics.heightPixels - 150;
//mViewPager.setLayoutParams(mLayoutParams);
mImgViewList = new ArrayList<ImageView>();
int len = picRes.length;
for(int i = 0; i < len ;i++){
ImageView view = new ImageView(mContext);
view.setBackgroundResource(picRes[i]);
mImgViewList.add(view);
}
//mViewPager.setAdapter(new ViewAdapha(mImgViewList));
}

public void initView(){
//mWndMgr.addView(mViewPager, mLayoutParams);
mImgView = mImgViewList.get(CurrentIndex);
mImgView.setLayoutParams(mLayoutParams);
mWndMgr.addView(mImgView, mLayoutParams);
//mWndMgr.updateViewLayout(mImgView, mLayoutParams);
}

private void startAutomaticRoll() {
viewpagerRunnable = new Runnable() {
@Override
public void run() {
//int nowIndex = mViewPager.getCurrentItem();    
//int count = mViewPager.getAdapter().getCount();    
if (CurrentIndex + 1 >= 3) {
//mViewPager.setCurrentItem(0);
CurrentIndex = 0;
} else {
CurrentIndex = CurrentIndex + 1;
}
mWndMgr.removeView(mImgView);
mImgView = mImgViewList.get(CurrentIndex);
mImgView.setLayoutParams(mLayoutParams);
//mViewPager.removeAllViews();
Log.i("index", "index="+CurrentIndex);
//mViewPager.removeAllViews();
//mViewPager.addView(mImgViewList.get(CurrentIndex));
mWndMgr.addView(mImgView, mLayoutParams);
//mWndMgr.updateViewLayout(mImgView, mLayoutParams);
MainThreadhandler.postDelayed(viewpagerRunnable, 3000);
}
};
MainThreadhandler.postDelayed(viewpagerRunnable, 3000);
}
}

 

这种方式比较戳，在图片切换之间，会有闪断的现象，也就是切换的不平滑。如果有知道的朋友，还请指点下是什么情况。或者是如何才能做到在我这种方式下，把ViewPager放到WindowManager里面，再把ImageView数组放在ViewPager里面，然后还能实现正常的切换的效果。

 

===========================================

又修改了下，效果更好了。哈哈～～～

public class MainActivity extends Activity {
	private Runnable viewpagerRunnable;
	private Handler MainThreadhandler;
	private WindowManager mWndMgr;
	private ImageView mImgView;
	private WindowManager.LayoutParams mLayoutParams;
	private Context mContext;
	private List<ImageView> mImgViewList;
	private int[] picRes = {R.drawable.first,R.drawable.second,R.drawable.third};
	int CurrentIndex = 0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mContext = this.getApplicationContext();
        MainThreadhandler = new Handler();
        prepareView();
        initView();
        startAutomaticRoll();
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
    
    private void prepareView(){
    	new ViewPager(mContext);
		mWndMgr = (WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE);
		DisplayMetrics outMetrics = new DisplayMetrics();
		mWndMgr.getDefaultDisplay().getMetrics(outMetrics);
		mLayoutParams = new WindowManager.LayoutParams();
		mLayoutParams.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
		mLayoutParams.width = outMetrics.widthPixels;
		mLayoutParams.height = outMetrics.heightPixels - 150;
    	mImgViewList = new ArrayList<ImageView>();
    	int len = picRes.length;
    	for(int i = 0; i < len ;i++){
    		ImageView view = new ImageView(mContext);
    		view.setBackgroundResource(picRes[i]);
    		mImgViewList.add(view);
    	}
    }
    
    public void initView(){
		mImgView = mImgViewList.get(CurrentIndex);
		mImgView.setLayoutParams(mLayoutParams);
		mWndMgr.addView(mImgView, mLayoutParams);
	}
    
    private void startAutomaticRoll() {
		viewpagerRunnable = new Runnable() {
			@Override
			public void run() {				
				if (CurrentIndex + 1 >= 3) {
					CurrentIndex = 0;
				} else {
					CurrentIndex = CurrentIndex + 1;
				}
				mImgView.setBackgroundResource(picRes[CurrentIndex]);
				Log.i("index", "index="+CurrentIndex);
				MainThreadhandler.postDelayed(viewpagerRunnable, 3000);
			}
		};
		MainThreadhandler.postDelayed(viewpagerRunnable, 3000);
	}
}