本节引言：
本节是ListView这个小节的最后一节，给大家带来的是ListView多布局Item的实现，
假如他是用一个ListView做的，那么一个ListView上不就有两种不同的Item咯！
1.要点讲解：
重写getItemViewType()方法对应View是哪个类别，以及getViewTypeCount()方法iew返回
2.代码实现：
这里的话直接用上一节的两个布局，然后另外写一个Adapter重写要点中的几个几个地方：
MutiLayoutAdapter.java ：
/**
* Created by Jay on 2015/9/23 0023.
*/
public class MutiLayoutAdapter extends BaseAdapter{
//定义两个类别标志
private static final int TYPE_BOOK = 0;
private static final int TYPE_APP = 1;
private Context mContext;
private ArrayList mData = null;
public MutiLayoutAdapter(Context mContext,ArrayList mData) {
this.mContext = mContext;
this.mData = mData;
}
@Override
public int getCount() {
return mData.size();
}
@Override
public Object getItem(int position) {
return mData.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
//多布局的核心，通过这个判断类别
@Override
public int getItemViewType(int position) {
if (mData.get(position) instanceof App) {
return TYPE_APP;
} else if (mData.get(position) instanceof Book) {
return TYPE_BOOK;
} else {
return super.getItemViewType(position);
}
}
//类别数目
@Override
public int getViewTypeCount() {
return 2;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
int type = getItemViewType(position);
ViewHolder1 holder1 = null;
ViewHolder2 holder2 = null;
if(convertView == null){
switch (type){
case TYPE_APP:
holder1 = new ViewHolder1();
convertView = LayoutInflater.from(mContext).inflate(R.layout.item_one, parent, false);
holder1.img_icon = (ImageView) convertView.findViewById(R.id.img_icon);
holder1.txt_aname = (TextView) convertView.findViewById(R.id.txt_aname);
convertView.setTag(R.id.Tag_APP,holder1);
break;
case TYPE_BOOK:
holder2 = new ViewHolder2();
convertView = LayoutInflater.from(mContext).inflate(R.layout.item_two, parent, false);
holder2.txt_bname = (TextView) convertView.findViewById(R.id.txt_bname);
holder2.txt_bauthor = (TextView) convertView.findViewById(R.id.txt_bauthor);
convertView.setTag(R.id.Tag_Book,holder2);
break;
}
}else{
switch (type){
case TYPE_APP:
holder1 = (ViewHolder1) convertView.getTag(R.id.Tag_APP);
break;
case TYPE_BOOK:
holder2 = (ViewHolder2) convertView.getTag(R.id.Tag_Book);
break;
}
}
Object obj = mData.get(position);
//设置下控件的值
switch (type){
case TYPE_APP:
App app = (App) obj;
if(app != null){
holder1.img_icon.setImageResource(app.getaIcon());
holder1.txt_aname.setText(app.getaName());
}
break;
case TYPE_BOOK:
Book book = (Book) obj;
if(book != null){
holder2.txt_bname.setText(book.getbName());
holder2.txt_bauthor.setText(book.getbAuthor());
}
break;
}
return convertView;
}
//两个不同的ViewHolder
private static class ViewHolder1{
ImageView img_icon;
TextView txt_aname;
}
private static class ViewHolder2{
TextView txt_bname;
TextView txt_bauthor;
}
}
这里有个地方要注意的，convertView.setTag(R.id.Tag_APP,holder1);我们平时都直接
The key must be an application-specific resource id
当然你也可以在res/values/下另外创建一个ids.xml文件，把上面这段代码贴上去！
MainActivity.java ：
public class MainActivity extends AppCompatActivity {
private static final int TYPE_BOOK = 0;
private static final int TYPE_APP = 1;
private ListView list_content;
private ArrayList mData = null;
private MutiLayoutAdapter myAdapter = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//数据准备：
mData = new ArrayList();
for(int i = 0;i
上面随机生成0和1，0就往集合中添加一个Book的对象，1的话就添加一个App的对象！
3.代码下载：
ListViewDemo6.zip
本节小结：
好的，本节给大家讲解了ListView Item多布局的实现，就是两个方法的重写，
然后getView()做下判断，设置不同的布局而已~代码非常简单~
关于ListView的知识就告一段落吧，当然ListView的知识并不止这些，
异步加载，优化等等，这些我们都会在进阶部分进行学习~就说这么多，谢谢~
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