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);
            }
        });