解决安卓开发中listview与checkbox等控件一起使用的问题

来源:互联网 发布:sqlserver分页sql语句 编辑:程序博客网 时间:2024/05/16 06:07

之前做一个个人项目的时候在listview中加入了checkbox控件,但是发现选择一个checkbox之后,其余某个checkbox也会被选择,经过6个小时的努力终于解决了这个问题。


要解决这个问题我们就要了解首先安卓的listview是有缓存和复用机制的,关于这点如果不了解的话可以点击这个链接,里面有浅显易懂的解释:

http://blog.csdn.net/lovehong0306/article/details/7498025

(注意:这个链接是转载的,感谢原作者)


之所以会出现checkbox之间选择之后相互关联就是因为这个复用机制再捣乱。


所以现在我们要做的就是手动的保存下每个checkbox是否被选择的状态,当系统调用getView显示checkbox的时候通过我们自己保存下的状态来决定checkbox应该被设置选中还是未选中。在代码中我选择使用ArrayList来保存checkbox的选中状态。


下面是代码:

1.主activity

<pre name="code" class="java">package com.Dropout.Four;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;import android.app.Activity;import android.content.Context;import android.content.Intent;import android.os.Bundle;import android.support.v7.appcompat.R.integer;import android.util.Log;import android.view.LayoutInflater;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.View.OnClickListener;import android.view.ViewGroup;import android.widget.ArrayAdapter;import android.widget.Button;import android.widget.CheckBox;import android.widget.CompoundButton;import android.widget.CompoundButton.OnCheckedChangeListener;import android.widget.ListView;import android.widget.SimpleAdapter;public class BuyActivity extends Activity {private Button bt_ok;    private Button bt_cancel;    private ListView lv;     public static ArrayList<Boolean> list_bool;    private MyAdapter ma;    private List<Map<String,String>> list =new ArrayList<Map<String,String>>();    private SimpleAdapter sa =null;    private ArrayList<Boolean> checked=new ArrayList<Boolean>();@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_buy);for(int i=0;i<(MainActivity.list).size();i++){checked.add(false);}//初始化list_boolilist_bool = new ArrayList<Boolean>();for (int i = 0;i<MainActivity.list.size();i++){list_bool.add(false);}bt_ok = (Button)findViewById(R.id.button1);bt_ok.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View arg0) {    Intent in=new Intent(BuyActivity.this,BuyingActivity.class);    BuyActivity.this.finish();    BuyActivity.this.startActivity(in);    }});bt_cancel = (Button)findViewById(R.id.button2);bt_cancel.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View arg0) {BuyActivity.this.finish();}});lv =(ListView)findViewById(R.id.listView1);    ma = new MyAdapter(BuyActivity.this,R.layout.choose_buy,MainActivity.list);   lv.setAdapter(ma);      /*for (int i =0; i<MainActivity.tot_people;i++){Map<String,String> map = new HashMap<String,String>();map.put("name",MainActivity.list.get(i));list.add(map);}sa = new SimpleAdapter(this,list,R.layout.choose_buy,new String[]{"name"},        new int[]{R.id.checkBox1});lv.setAdapter(sa);        */}  private class MyAdapter extends ArrayAdapter<String>{private int resource;    public MyAdapter(Context context,int resourceId, ArrayList<String> s) {super(context,resourceId,s);resource = resourceId; }@Overridepublic View getView(int position, View convertView, ViewGroup parent) {if(convertView==null){convertView=BuyActivity.this.getLayoutInflater().inflate(R.layout.choose_buy, null);}CheckBox cb = (CheckBox)convertView.findViewById(R.id.checkBox1);cb.setText(MainActivity.list.get(position));cb.setChecked(checked.get(position));cb.setOnClickListener(new MyListener(position));return convertView;     }private class MyListener implements OnClickListener{private int key;public MyListener(int key){this.key=key;}@Overridepublic void onClick(View v) {// TODO 自动生成的方法存根if(!checked.get(key)){checked.set(key,true);return;}if(checked.get(key)){checked.set(key,false);return;}       }           }      }      }


</pre><pre name="code" class="java">
2.定义了checkbox的布局文件:

<?xml version="1.0" encoding = "utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/myLayout1"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >    <CheckBox        android:id="@+id/checkBox1"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_weight="0.42"        android:text="CheckBox"          /></LinearLayout>

3.主Activity的布局文件:

<AbsoluteLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/AbsoluteLayout1"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.Dropout.Four.BuyActivity" >    <TextView        android:id="@+id/textView1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_x="13dp"        android:layout_y="12dp"        android:text="请选择参与本次消费的成员:" />    <ListView        android:id="@+id/listView1"        android:layout_width="223dp"        android:layout_height="312dp"        android:layout_x="29dp"        android:layout_y="38dp" >    </ListView>    <Button        android:id="@+id/button1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_x="53dp"        android:layout_y="378dp"        android:text="确定" />    <Button        android:id="@+id/button2"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_x="168dp"        android:layout_y="378dp"        android:text="返回" /></AbsoluteLayout>




0 0
原创粉丝点击