监听键盘的弹出与消失

使用：getViewTreeObserver().addOnGlobalLayoutListener(mGlobalLayoutListener);

注意：记得在结束时remove掉（getViewTreeObserver().removeGlobalOnLayoutListener(mGlobalLayoutListener);）

private ViewTreeObserver.OnGlobalLayoutListener mGlobalLayoutListener=new ViewTreeObserver.OnGlobalLayoutListener(){    @Override    public void onGlobalLayout() {        Rect r = new Rect();        ((BindDeviceActivity)getContext()).getWindow().getDecorView().getWindowVisibleDisplayFrame(r);        int screenHeight =  ((BindDeviceActivity)getContext()).getWindow().getDecorView().getRootView().getHeight();        int heightDifference = screenHeight - r.bottom;        L.e("Keyboard Size", "Size: " + heightDifference);        if (heightDifference == 0) {            L.e("input window hidden");                    }else {            L.e("input window show");                    }    }};