ListView加载不同布局

http://www.tuicool.com/articles/MBvABz 这边文章写得图片的详细。

以下为自己的简单尝试

效果图：



以上有两种布局，紫色为一种布局（TextView加Button），红色为另一种布局（ImageView加Button）

adapter代码：

public class TestAdapter extends BaseAdapter {
List<Entity> list;
Context mContext;
LayoutInflater inflater;
final int VIEW_TYPE = 2;
final int TYPE_1 = 0;
final int TYPE_2 = 1;

public TestAdapter(Context mContext,List<Entity> list) {
this.list = list;
this.mContext = mContext;
}

@Override
public int getCount() {
return list==null?0:list.size();
}

@Override
public Object getItem(int position) {
return list.get(position);
}

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

// 每个convert view都会调用此方法，获得当前所需要的view样式
@Override
public int getItemViewType(int position) {
int type_now=list.get(position).getType();
switch (type_now){
case TYPE_1:return TYPE_1;
case TYPE_2: return TYPE_2;
default:return TYPE_1;
}
}

@Override
public int getViewTypeCount() {
return VIEW_TYPE;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder1 holder1 = null;
ViewHolder2 holder2 = null;
int currentType = getItemViewType(position);
if (convertView == null) {
inflater = LayoutInflater.from(mContext);
// 按当前所需的样式，确定new的布局
switch (currentType) {
case TYPE_1:
holder1 = new ViewHolder1();
convertView = inflater.inflate(R.layout.layout1,parent, false);
holder1.title = (TextView) convertView.findViewById(R.id.title);
holder1.btn1 = (Button) convertView.findViewById(R.id.button1);
convertView.setTag(holder1);
break;
case TYPE_2:
holder2 = new ViewHolder2();
convertView = inflater.inflate(R.layout.layout2,parent, false);
holder2.image = (ImageView) convertView.findViewById(R.id.image);
holder2.btn2 = (Button) convertView.findViewById(R.id.button2);
convertView.setTag(holder2);
break;
default:
break;
}
}
Entity entity=list.get(position);
switch (currentType) {
case TYPE_1:
holder1 = (ViewHolder1) convertView.getTag();
holder1.title.setText(entity.getTitle());
holder1.btn1.setText(entity.getButtonName());
break;
case TYPE_2:
holder2 = (ViewHolder2) convertView.getTag();
holder2.image.setImageResource(entity.getImage());
holder2.btn2.setText(entity.getButtonName());
break;
}
return convertView;
}

public class ViewHolder1 {
TextView title;
Button btn1;
}

public class ViewHolder2 {
ImageView image;
Button btn2;
}
}

通过list传递的对象entity的type属性来选择与之匹配的布局。

我们在使用ListView分类的时候会用到两个方法getItemViewType和getViewTypeCount，getViewTypeCount这个方法告诉ListView我共有多少种item，getItemViewType方法告诉ListView每行该显示哪种item，并且该方法中返回的type类型必须为整数且不能大于getViewTypeCount返回的数。意思是getItemViewType有2个返回值，那么getViewTypeCount的返回值必须大于等于2.