ListView 嵌套 GridView 大法

起因

项目需求要用表格形式实现布局

但是！！！需要下拉和上拉加载数据。

因为项目里只有github里的XListView改造的ListView，又因为本人太笨太懒，不想写上拉下来gridview。。

废话不多说

1、定义一个主视图 listview.xml

<ListView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/listview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipToPadding="false"
android:divider="@null"
android:dividerHeight="10dp"
android:padding="10dp"></ListView>

就这样，因为本例讲的是listview嵌套gridview，不涉及上拉下拉，所以就用普通的listview咯

2、自定义GridView—NoScrollGridView

其实不自定义也行，当时为了防止gridview显示补全blabla的，还是写一个保证万无一失。

public class NoScrollGridView extends GridView {
public NoScrollGridView(Context context, AttributeSet attrs) {
super(context, attrs);
}

public NoScrollGridView(Context context) {
super(context);
}

public NoScrollGridView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}

public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
//核心在此
int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, expandSpec+50);
}
}

3、定义ListView单项布局 listview_item.xml

<?xml version="1.0" encoding="utf-8"?>
<com.example.shen.sample.NoScrollGridView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gridview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:numColumns="2"
android:stretchMode="columnWidth"
android:horizontalSpacing="10dp"
android:verticalSpacing="10dp" />
<!-- 注意
android:numColumns="2"
android:stretchMode="columnWidth"
-->

4、定义GridView单项布局 gridview_item.xml

<?xml version="1.0" encoding="utf-8"?>
<ImageView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:id="@+id/imageview"
android:background="#000"
android:layout_height="80dp" />

5、定义GridView的数据适配器 GridViewAdapter.java

/**
* Created by Shen on 2015/10/29.
* 普通的适配器
*/
public class GridViewAdapter extends BaseAdapter {

//数据源
private List<MainActivity.Bean> mList = new ArrayList<>();

private Context mContext;

public GridViewAdapter(Context context) {
super();
this.mContext = context;
}

public List<MainActivity.Bean> getmList() {
return mList;
}

public void setmList(List<MainActivity.Bean> mList) {
this.mList = mList;
}

@Override
public int getCount() {
return mList.size();
}

@Override
public MainActivity.Bean getItem(int position) {
return mList.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = LayoutInflater.from(mContext).inflate(R.layout.gridview_item, parent, false);
holder = new ViewHolder(convertView);
} else {
holder = (ViewHolder) convertView.getTag();
}
//设置图片内容，本例木有图片
//        holder.iv.setImageResource(getItem(position));
return convertView;
}

class ViewHolder {

ImageView iv;

public ViewHolder(View view) {
iv = (ImageView) view.findViewById(R.id.imageview);
view.setTag(this);
}
}
}

6、定义ListView的数据适配器 ListViewAdapter.java

/**
* Created by Shen on 2015/10/29.
* ListView的数据源
* 在这里给gridview设置数据
* 重要
*/
public class ListViewAdapter extends BaseAdapter {

//数据源
private List<MainActivity.Bean> mList = new ArrayList<>();

//列数
private int mColumn = 2;

private Context mContext;

public ListViewAdapter(Context context, List<MainActivity.Bean> list) {
super();
this.mContext = context;
this.mList = list;
}

/**
* 这部很重要
*(核心)
* @return listview的行数
*/
@Override
public int getCount() {
int count = mList.size() / mColumn;
if (mList.size() % mColumn > 0) {
count++;
}
return count;
}

@Override
public MainActivity.Bean getItem(int position) {
return mList.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = LayoutInflater.from(mContext).inflate(R.layout.listview_item, parent, false);
holder = new ViewHolder(convertView);
} else {
holder = (ViewHolder) convertView.getTag();
}

//定义gridView的数据源
List<MainActivity.Bean> list = new ArrayList<>();

//根据列数，将数据塞进去(核心)
for (int i = 0; i < mColumn; i++) {
int n = position * mColumn + i;
if (n < mList.size()) {
list.add(getItem(n));
}
}

//更新数据源(核心)
holder.adapter.setmList(list);
holder.adapter.notifyDataSetChanged();
return convertView;
}

class ViewHolder {

GridView gridView;
GridViewAdapter adapter;

public ViewHolder(View view) {

gridView = (GridView) view.findViewById(R.id.gridview);
//将adapter定义在此，优化滑动效果(核心)
adapter = new GridViewAdapter(mContext);
//在此设置适配器，数据源在getView中添加(核心)
gridView.setAdapter(adapter);

view.setTag(this);
}
}
}

最后MainActivity.java

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.listview);

ListView listview = (ListView) findViewById(R.id.listview);
List<Bean> list = new ArrayList();
for (int i = 0; i < 19; i++) {
list.add(new Bean());
}
ListViewAdapter adapter = new ListViewAdapter(this, list);
listview.setAdapter(adapter);
}

public static class Bean {

}
}

大功告成！