1:FragmentHack4.java
/**
* Created by y on 15-1-2.
*/
public class FragmentHack4 extends Fragment{ View view;
List<String> names; ListView lvNames;
NameSectionAdapter adapter;
TextView tvHeader;
int topVisiblePos; @Override
public void onAttach(Activity activity) {
super.onAttach(activity); names = new ArrayList<String>(); //测试数据
String []t={"A","B","C","D","E","F"};
for(int i=0;i<t.length;i++){
for(int j=0;j<10;j++){
names.add(t[i]+"00"+j);
}
} } @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_hack4, container,false); tvHeader = (TextView)view.findViewById(R.id.tvHeader);
lvNames = (ListView)view.findViewById(R.id.lvNames); adapter = new NameSectionAdapter(getActivity(),R.layout.list_name_item,names);
lvNames.setAdapter(adapter); //设置第一个分组栏数据
setTopHeader(0); lvNames.setOnScrollListener( lvOnScrollListener()); return view;
} AbsListView.OnScrollListener lvOnScrollListener(){
return new AbsListView.OnScrollListener() {
@Override
public void onScrollStateChanged(AbsListView absListView, int i) { } @Override
public void onScroll(AbsListView absListView, int i, int i2, int i3) { if(i!=topVisiblePos){ topVisiblePos = i; setTopHeader(i);
}
}
};
} private void setTopHeader(int pos){
tvHeader.setText(names.get(pos).substring(0,1));
}
}
2:NameSectionAdapter.java
/**
* Created by y on 15-1-2.
*/
public class NameSectionAdapter extends ArrayAdapter<String>{
private int resourceId; public NameSectionAdapter(Context context, int resourceId, List<String> objects){
super(context,resourceId,objects); this.resourceId = resourceId;
} @Override
public View getView(int position, View convertView, ViewGroup parent) {
String name = getItem(position);
ViewHolder holder; if(convertView==null){
convertView = LayoutInflater.from(getContext()).inflate(resourceId,null);
holder = new ViewHolder(); holder.tvHeader = (TextView)convertView.findViewById(R.id.tvHeader);
holder.tvName = (TextView)convertView.findViewById(R.id.tvName); convertView.setTag(holder);
}else{
holder = (ViewHolder)convertView.getTag();
} holder.tvName.setText(name); //如果是第一项或者首字母发生了变化,则显示分组栏,否则隐藏
if(position==0 || getItem(position-1).charAt(0)!=name.charAt(0)){
holder.tvHeader.setVisibility(View.VISIBLE);
holder.tvHeader.setText(name.substring(0,1));
}else{
holder.tvHeader.setVisibility(View.GONE);
} return convertView;
} static class ViewHolder{
public TextView tvHeader;
public TextView tvName;
}
}
3:布局文件:
(1)fragment_hack4.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"> <ListView
android:id="@+id/lvNames"
android:layout_width="match_parent"
android:layout_height="match_parent"/> <include layout="@layout/list_header"/>
</FrameLayout>
(2)list_header.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/tvHeader"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#0000ff"
android:textColor="#ffffff"
style="@android:style/TextAppearance.Large"
android:textStyle="bold"/>
(3)list_name_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"> <include layout="@layout/list_header"/> <TextView
android:id="@+id/tvName"
style="@android:style/TextAppearance.Small"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
4:运行结果