From d5e5793b62ab3489008b569d699849dbbd5c413d Mon Sep 17 00:00:00 2001
From: XingRong Dong <dongxingrong@163.com>
Date: Sun, 14 Jun 2015 17:02:59 +0800
Subject: [PATCH] Update MainActivity.java
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在使用过程中发现了 demo 有两个漏洞：1、列表数据为0的时候出现崩溃；2、列表数据为0的情况下，下拉无法显示头部；
---
 .../src/com/ryg/expandable/MainActivity.java          | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/PinnedHeaderExpandableListView/src/com/ryg/expandable/MainActivity.java b/PinnedHeaderExpandableListView/src/com/ryg/expandable/MainActivity.java
index adc448e..4fc9a6d 100644
--- a/PinnedHeaderExpandableListView/src/com/ryg/expandable/MainActivity.java
+++ b/PinnedHeaderExpandableListView/src/com/ryg/expandable/MainActivity.java
@@ -275,9 +275,12 @@ public View getPinnedHeader() {
 
     @Override
     public void updatePinnedHeader(View headerView, int firstVisibleGroupPos) {
-        Group firstVisibleGroup = (Group) adapter.getGroup(firstVisibleGroupPos);
-        TextView textView = (TextView) headerView.findViewById(R.id.group);
-        textView.setText(firstVisibleGroup.getTitle());
+        if (adapter.getGroupCount() > 0) { // 防止列表在无数据的情况崩溃
+                Group firstVisibleGroup = (Group) adapter.getGroup(firstVisibleGroupPos);
+                TextView textView = (TextView) headerView.findViewById(R.id.group);
+                textView.setText(firstVisibleGroup.getTitle());
+            }
+        
     }
 
     @Override
@@ -286,6 +289,8 @@ public boolean giveUpTouchEvent(MotionEvent event) {
             View view = expandableListView.getChildAt(0);
             if (view != null && view.getTop() >= 0) {
                 return true;
+            } else if (adapter.getGroupCount == 0) { //保证列表没有数据的情况下，头部隐藏后还能继续下拉显示出来
+                    return true;
             }
         }
         return false;