Usage of ListView nested GridView and precautions

MainActivity is as follows: Copy codeThe Code is as follows: package cn. testlistviewandgridview;
Import java. util. ArrayList;
Import java. util. HashMap;
Import android. app. Activity;
Import android. OS. Bundle;
Import android. widget. ListView;
/**
* Demo description:
* Usage of ListView nested GridView
* That is, each Item in the ListView contains a GridView
*
* Note:
* Because ListView and GridView are slip controls.
* Therefore, you need to customize the GridView and override its onMeasure () method.
* In this method, set the height of the GridView to the size of wrap_content. Otherwise
* Only a small portion of the content can be displayed.
*
* References:
* 1 http://bbs.csdn.net/topics/380245627
* 2 http://blog.csdn.net/lsong89/article/details/8598856
* Thank you very much
*/
Public class MainActivity extends Activity {
Private ListView mListView;
Private ListViewAdapter mListViewAdapter;
Private ArrayList <HashMap <String, Object> mArrayList;
@ Override
Protected void onCreate (Bundle savedInstanceState ){
Super. onCreate (savedInstanceState );
SetContentView (R. layout. main );
Init ();
}
Private void init (){
MListView = (ListView) findViewById (R. id. listView );
InitData ();
MListViewAdapter = new ListViewAdapter (mArrayList, MainActivity. this );
MListView. setAdapter (mListViewAdapter );
}
Private void initData (){
MArrayList = new ArrayList <HashMap <String, Object> ();
HashMap <String, Object> hashMap = null;
ArrayList <HashMap <String, Object> arrayListForEveryGridView;

For (int I = 0; I <10; I ++ ){
ArrayListForEveryGridView = new ArrayList <HashMap <String, Object> ();
For (int j = 0; j <5; j ++ ){
HashMap = new HashMap <String, Object> ();
HashMap. put ("content", "I =" + I + ", j =" + j );
ArrayListForEveryGridView. add (hashMap );
}
MArrayList. add (arrayListForEveryGridView );
}

}
}

The ListViewAdapter is as follows:Copy codeThe Code is as follows: package cn. testlistviewandgridview;
Import java. util. ArrayList;
Import java. util. HashMap;
Import android. content. Context;
Import android. view. LayoutInflater;
Import android. view. View;
Import android. view. ViewGroup;
Import android. widget. BaseAdapter;
Import android. widget. GridView;
Import android. widget. ImageView;
Public class ListViewAdapter extends BaseAdapter {
Private ArrayList <HashMap <String, Object> mList;
Private Context mContext;

Public ListViewAdapter (ArrayList <HashMap <String, Object> mList, Context mContext ){
Super ();
This. mList = mList;
This. mContext = mContext;
}
@ Override
Public int getCount (){
If (mList = null ){
Return 0;
} Else {
Return this. mList. size ();
}
}
@ Override
Public Object getItem (int position ){
If (mList = null ){
Return null;
} Else {
Return this. mList. get (position );
}
}
@ Override
Public long getItemId (int position ){
Return position;
}
@ Override
Public View getView (int position, View convertView, ViewGroup parent ){
ViewHolder holder = null;
If (convertView = null ){
Holder = new ViewHolder ();
ConvertView = LayoutInflater. from
(This. mContext). inflate (R. layout. listview_item, null, false );
Holder. imageView = (ImageView) convertView. findViewById (R. id. listview_item_imageview );
Holder. gridView = (GridView) convertView. findViewById (R. id. listview_item_gridview );
ConvertView. setTag (holder );
} Else {
Holder = (ViewHolder) convertView. getTag ();
}

If (this. mList! = Null ){
If (holder. imageView! = Null ){
Holder. imageView. setImageDrawable
(MContext. getResources (). getDrawable (R. drawable. e ));
}
If (holder. gridView! = Null ){
ArrayList <HashMap <String, Object> arrayListForEveryGridView = this. mList. get (position );
GridViewAdapter gridViewAdapter = new GridViewAdapter (mContext, arrayListForEveryGridView );
Holder. gridView. setAdapter (gridViewAdapter );
}
}
Return convertView;
}

Private class ViewHolder {
ImageView imageView;
GridView;
}
}

GridViewAdapter is as follows:Copy codeThe Code is as follows: package cn. testlistviewandgridview;
Import java. util. ArrayList;
Import java. util. HashMap;
Import android. content. Context;
Import android. view. LayoutInflater;
Import android. view. View;
Import android. view. View. OnClickListener;
Import android. view. ViewGroup;
Import android. widget. BaseAdapter;
Import android. widget. Button;
Import android. widget. Toast;
Public class GridViewAdapter extends BaseAdapter {
Private Context mContext;
Private ArrayList <HashMap <String, Object> mList;

Public GridViewAdapter (Context mContext, ArrayList <HashMap <String, Object> mList ){
Super ();
This. mContext = mContext;
This. mList = mList;
}
@ Override
Public int getCount (){
If (mList = null ){
Return 0;
} Else {
Return this. mList. size ();
}
}
@ Override
Public Object getItem (int position ){
If (mList = null ){
Return null;
} Else {
Return this. mList. get (position );
}
}
@ Override
Public long getItemId (int position ){
Return position;
}
@ Override
Public View getView (final int position, View convertView, ViewGroup parent ){
ViewHolder holder = null;
If (convertView = null ){
Holder = new ViewHolder ();
ConvertView = LayoutInflater. from
(This. mContext). inflate (R. layout. gridview_item, null, false );
Holder. button = (Button) convertView. findViewById (R. id. gridview_item_button );
ConvertView. setTag (holder );

} Else {
Holder = (ViewHolder) convertView. getTag ();
}

If (this. mList! = Null ){
HashMap <String, Object> hashMap = this. mList. get (position );
If (holder. button! = Null ){
Holder. button. setText (hashMap. get ("content"). toString ());
Holder. button. setOnClickListener (new OnClickListener (){
@ Override
Public void onClick (View v ){
Toast. makeText (mContext, "th" + (position + 1) + ", Toast. LENGTH_SHORT). show ();
}
});
}
}
Return convertView;
}

Private class ViewHolder {
Button button;
}
}

NoScrollGridView is as follows:Copy codeThe Code is as follows: package cn. testlistviewandgridview;
Import android. content. Context;
Import android. util. AttributeSet;
Import android. widget. GridView;
Public class NoScrollGridView extends GridView {
Public NoScrollGridView (Context context ){
Super (context );

}
Public NoScrollGridView (Context context, AttributeSet attrs ){
Super (context, attrs );
}

@ Override
Protected void onMeasure (int widthMeasureSpec, int heightMeasureSpec ){
Int expandSpec = MeasureSpec. makeMeasureSpec (Integer. MAX_VALUE> 2, MeasureSpec. AT_MOST );
Super. onMeasure (widthMeasureSpec, expandSpec );
}
}

Main. xml is as follows:Copy codeThe Code is as follows: <RelativeLayout
Xmlns: android = "http://schemas.android.com/apk/res/android"
Xmlns: tools = "http://schemas.android.com/tools"
Android: layout_width = "match_parent"
Android: layout_height = "match_parent"
>
<ListView
Android: id = "@ + id/listView"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: focusable = "false"
/>
</RelativeLayout>

Listview_item.xml is as follows:Copy codeThe Code is as follows: <? 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"
>
<ImageView
Android: id = "@ + id/listview_item_imageview"
Android: layout_width = "fill_parent"
Android: layout_height = "20dip"
Android: scaleType = "fitXY"
Android: src = "@ drawable/e"
/>
<Cn. testlistviewandgridview. NoScrollGridView
Android: id = "@ + id/listview_item_gridview"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: stretchMode = "columnWidth"
Android: verticalSpacing = "5dip"
Android: horizontalSpacing = "5dip"
Android: numColumns = "2"/>
</LinearLayout>

Gridview_item.xml is as follows:Copy codeThe Code is as follows: <? 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 = "match_parent"
Android: orientation = "horizontal"
Android: padding = "10dip"
>
<Button
Android: id = "@ + id/gridview_item_button"
Android: layout_width = "140dip"
Android: layout_height = "40dip"
Android: background = "@ drawable/e"
Android: textColor = "@ android: color/background_light"
Android: clickable = "true"
/>
</LinearLayout>