我正在使用在网络上找到的Expandable ListView示例
活动:
public class ExpandableListViewActivity extends ExpandableListActivity { /** * strings for group elements */ static final String arrGroupelements[] = { "India","Australia","England","South Africa" }; /** * strings for child elements */ static final String arrChildelements[][] = { { "Sachin Tendulkar","Raina","Dhoni","Yuvi" },{ "Ponting","Adam Gilchrist","Michael Clarke" },{ "Andrew Strauss","kevin Peterson","Nasser Hussain" },{ "Graeme Smith","AB de villiers","Jacques Kallis" } }; DisplayMetrics metrics; int width; ExpandableListView expList; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); expList = getExpandableListView(); metrics = new DisplayMetrics(); getWindowManager().getDefaultDisplay().getMetrics(metrics); width = metrics.widthPixels; // this code for adjusting the group indicator into right side of the // view expList.setIndicatorBounds(width - GetDipsFromPixel(50),width - GetDipsFromPixel(10)); expList.setAdapter(new ExpAdapter(this)); expList.setOnGroupExpandListener(new OnGroupExpandListener() { public void onGroupExpand(int groupPosition) { Log.e("onGroupExpand","OK"); } }); expList.setOnGroupCollapseListener(new OnGroupCollapseListener() { public void onGroupCollapse(int groupPosition) { Log.e("onGroupCollapse","OK"); } }); expList.setOnChildClickListener(new OnChildClickListener() { public boolean onChildClick(ExpandableListView parent,View v,int groupPosition,int childPosition,long id) { Log.e("OnChildClickListener","OK"); return false; } }); } public int GetDipsFromPixel(float pixels) { // Get the screen's density scale final float scale = getResources().getDisplayMetrics().density; // Convert the dps to pixels,based on density scale return (int) (pixels * scale + 0.5f); } }
适配器:
public class ExpAdapter extends BaseExpandableListAdapter { private Context myContext; public ExpAdapter(Context context) { myContext = context; } public Object getChild(int groupPosition,int childPosition) { return null; } public long getChildId(int groupPosition,int childPosition) { return 0; } public View getChildView(int groupPosition,boolean isLastChild,View convertView,ViewGroup parent) { if (convertView == null) { LayoutInflater inflater = (LayoutInflater) myContext .getSystemService(Context.LAYOUT_INFLATER_SERVICE); convertView = inflater.inflate(R.layout.child_row,null); } TextView tvPlayerName = (TextView) convertView .findViewById(R.id.tvPlayerName); tvPlayerName .setText(ExpandableListViewActivity.arrChildelements[groupPosition][childPosition]); return convertView; } public int getChildrenCount(int groupPosition) { return ExpandableListViewActivity.arrChildelements[groupPosition].length; } public Object getGroup(int groupPosition) { return null; } public int getGroupCount() { return ExpandableListViewActivity.arrGroupelements.length; } public long getGroupId(int groupPosition) { return 0; } public View getGroupView(int groupPosition,boolean isExpanded,ViewGroup parent) { if (convertView == null) { LayoutInflater inflater = (LayoutInflater) myContext .getSystemService(Context.LAYOUT_INFLATER_SERVICE); convertView = inflater.inflate(R.layout.group_row,null); } TextView tvGroupName = (TextView) convertView .findViewById(R.id.tvGroupName); tvGroupName .setText(ExpandableListViewActivity.arrGroupelements[groupPosition]); return convertView; } public boolean hasStableIds() { return false; } public boolean isChildSelectable(int groupPosition,int childPosition) { return true; } }
main.xml中:
<?xml version="1.0" encoding="UTF-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <ExpandableListView android:id="@+id/android:list" android:layout_width="fill_parent" android:layout_height="fill_parent" android:groupIndicator="@drawable/group_indicator" > <TextView android:id="@+id/android:empty" android:layout_width="fill_parent" android:layout_height="fill_parent" android:text="No Items" > </TextView> </ExpandableListView> </LinearLayout>
我试过这个解决方案,但没有工作:(
Android: Custom ListAdapter extending BaseAdapter crashes on application launch
它被告知要添加第三个参数“假”,到inflater.inflate(R.layout.group_row,null,false);
解决方法
将TextView移动到ExpandableListView元素之外:
<?xml version="1.0" encoding="UTF-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <ExpandableListView android:id="@+id/android:list" android:layout_width="fill_parent" android:layout_height="fill_parent" android:groupIndicator="@drawable/group_indicator" > </ExpandableListView> <TextView android:id="@+id/android:empty" android:layout_width="fill_parent" android:layout_height="fill_parent" android:text="No Items" > </TextView> </LinearLayout>
AdapterView的子类(如ExpandableListView)不能在xml布局中拥有子项(就像您在布局中所做的那样).