android

ListView与RadioButton组合——自定义单选列表

Android自带的RadioButton单选框只支持添加文字，我们自己写Adapter实现自定义的RadioButton

首先item的XML源码

search_user_item.xml （现在只是文字+单选按钮+自定义背景，可以根据需要随意扩展）

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<?xml version="1.0" encoding="utf-8"?>  
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    android:id="@+id/search_user_list_item"  
    android:layout_width="fill_parent"  
    android:layout_height="30dp"  
    android:layout_marginBottom="10dp"  
    android:layout_marginTop="10dp"  
    android:background="@drawable/more_item_press"  
    android:gravity="center_vertical"  
    android:orientation="horizontal" >  
  
    <TextView  
        android:id="@+id/search_user_name"  
        android:layout_width="200dp"  
        android:layout_height="wrap_content"  
        android:layout_marginLeft="30dp"  
        android:gravity="left"  
        android:textColor="@android:color/black"  
        android:textSize="16sp" />  
  
    <RadioButton  
        android:id="@+id/radio_btn"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_marginLeft="10dp" />  
  
</LinearLayout>

Listview就是用系统自带的

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<ListView  
    android:id="@+id/search_user_list"  
    android:layout_width="fill_parent"  
    android:layout_height="200dp"  
    android:layout_marginLeft="5dp"  
    android:layout_marginRight="5dp"  
    android:paddingBottom="5dp"  
    android:cacheColorHint="@android:color/transparent"  
    android:divider="@null"  
    android:listSelector="@android:color/transparent"  
    android:visibility="gone" >  
</ListView>

再来是Adapter代码

SearchUserAdapter.java （具体改动写在代码注释里面）

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package ouc.sei.suxin.android.ui.adapter;  
  
import java.util.HashMap;  
import java.util.List;  
  
import ouc.sei.suxin.R;  
import android.content.Context;  
import android.view.LayoutInflater;  
import android.view.View;  
import android.view.ViewGroup;  
import android.widget.BaseAdapter;  
import android.widget.LinearLayout;  
import android.widget.RadioButton;  
import android.widget.TextView;  
  
public class SearchUserAdapter extends BaseAdapter {  
      
    private Context context;  
    private List<String> userList;  
    HashMap<String,Boolean> states=new HashMap<String,Boolean>();//用于记录每个RadioButton的状态，并保证只可选一个  


    public SearchUserAdapter(Context context, List<String> userList)  
    {  
        this.context = context;  
        this.userList= userList;  
    }  
      
    @Override  
    public int getCount() {  
        return userList.size();  
    }  
      
    @Override  
    public Object getItem(int position) {  
        return userList.get(position);  
    }  
      
    @Override  
    public long getItemId(int position) {  
        return position;  
    }  
      
    @Override  
    public View getView(final int position, View convertView, ViewGroup parent) {  
        ViewHolder holder;  
        if (convertView == null) {  
            convertView = LayoutInflater.from(context).inflate(R.layout.search_user_item, null);  
            holder = new ViewHolder();  
            holder.background = (LinearLayout) convertView.findViewById(R.id.search_user_list_item);  
            holder.userName = (TextView) convertView.findViewById(R.id.search_user_name);  
            convertView.setTag(holder);  
        }else{  
            holder=(ViewHolder) convertView.getTag();  
        }  
           final RadioButton radio=(RadioButton) convertView.findViewById(R.id.radio_btn);  
        holder.rdBtn = radio;  
          
        holder.userName.setText(userList.get(position));  
        //根据Item位置分配不同背景          
        if(userList.size() > 0)  
        {  
            if(userList.size() == 1)  
            {  
                holder.background.setBackgroundResource(R.drawable.more_item_press);  
            }  
            else{  
                if(position == 0){  
                    holder.background.setBackgroundResource(R.drawable.more_itemtop_press);  
                }  
                else if(position == userList.size()-1){  
                    holder.background.setBackgroundResource(R.drawable.more_itembottom_press);  
                }  
                else{  
                    holder.background.setBackgroundResource(R.drawable.more_itemmiddle_press);  
                }  
            }  
        }  
    //当RadioButton被选中时，将其状态记录进States中，并更新其他RadioButton的状态使它们不被选中      
           holder.rdBtn.setOnClickListener(new View.OnClickListener() {  
                 
               public void onClick(View v) {  
                   
                   //重置，确保最多只有一项被选中  
                   for(String key:states.keySet()){  
                       states.put(key, false);  
                         
                   }  
                   states.put(String.valueOf(position), radio.isChecked());  
                   SearchUserAdapter.this.notifyDataSetChanged();  
               }  
           });  
          
           boolean res=false;  
           if(states.get(String.valueOf(position)) == null || states.get(String.valueOf(position))== false){  
               res=false;  
               states.put(String.valueOf(position), false);  
           }  
           else  
               res = true;  
             
           holder.rdBtn.setChecked(res);  
      
        return convertView;  
    }  
      
    static class ViewHolder {  
       LinearLayout background;  
              TextView userName;  
              RadioButton rdBtn;  
    }  
}

List适配代码（与一般无异）：

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adapter = new SearchUserAdapter(this, searchUserList);  
searchUserLV.setAdapter(adapter);  
searchUserLV.setVisibility(View.VISIBLE);  
setListViewHeightBasedOnChildren(searchUserLV);

这里还根据内容动态设置了一下，具体函数如下：

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public void setListViewHeightBasedOnChildren(ListView listView) {  
  
    Adapter listAdapter = listView.getAdapter();  
  
    if (listAdapter == null) {  
        return;  
    }  
  
    int totalHeight = 0;  
    int viewCount = listAdapter.getCount();  
    for (int i = 0; i < viewCount; i++) {  
        View listItem = listAdapter.getView(i, null, listView);  
        listItem.measure(0, 0);  
        totalHeight += listItem.getMeasuredHeight();  
    }  
  
    ViewGroup.LayoutParams params = listView.getLayoutParams();  
  
    params.height = totalHeight  
            + (listView.getDividerHeight() * (listAdapter.getCount()-1)) + 10;//加10是为了适配自定义背景  
  
    listView.setLayoutParams(params);  
}

当需要获取ListView中RadioButton的选择状态时，可以直接看Adapter中的states，具体如下：

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// 根据RadioButton的选择情况确定用户名  
for (int i = 0, j = searchUserLV.getCount(); i < j; i++) {  
    View child = searchUserLV.getChildAt(i);  
    RadioButton rdoBtn = (RadioButton) child  
            .findViewById(R.id.radio_btn);  
    if (rdoBtn.isChecked())  
        searchUser = searchUserList.get(i);  
}

这里的searchUserList是调用后台服务获取的用户名列表，通过states获取选中用户名进行后续操作

效果图：