SupportV7包中 SwipeRefreshLayout 修改下拉控件的距离

  //修改下拉距离
         ViewTreeObserver vto = mCategoryResults.mSwipeRefreshLayout.getViewTreeObserver();
         vto.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
             public void onGlobalLayout() {

                 final DisplayMetrics metrics = getResources().getDisplayMetrics();
                 Float mDistanceToTriggerSync = Math.min(((View) mCategoryResults.mSwipeRefreshLayout.getParent()).getHeight() * 0.6f, 500 * metrics.density);

                 try {
                     Field field = SwipeRefreshLayout.class.getDeclaredField("mDistanceToTriggerSync");
                     field.setAccessible(true);
                     field.setFloat(mCategoryResults.mSwipeRefreshLayout, mDistanceToTriggerSync);
                 } catch (Exception e) {
                     e.printStackTrace();
                 }
                 ViewTreeObserver obs = mCategoryResults.mSwipeRefreshLayout.getViewTreeObserver();
                 obs.removeOnGlobalLayoutListener(this);
             }
         });