完美解决Android在listview添加checkbox实现单选多选操作问题

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在Android某些开发需求当中，有时候需要在listveiw中加入checkbox实现单选，多选操作。表面上看上去只是改变checkbox那么简单，然而实际开发中，实现起来并不是那么得心应手。尤其当listview比较多(比如屏幕最多只能显示10个item，但总共有12个item，也就是说listview的item数大于屏幕能够显示的item数)滑动屏幕的时候，由于适配器中getview()会重复使用被移除屏幕的item，所以会造成checkbox选择状态不正常的现象。自己在开发中碰到这样的问题很是苦恼，查了下资料，发现网上很少没有针对这类批量操作并没有一个完整的例子。搜了很多篇帖子才完美的实现这一常用的操作。所以在这里把这个Demo贴出来，供大家参考，希望能对大家有所帮助。

主界面的布局main.xml    这个就不多说什么

<?xml version="1.0" encoding="utf-8"?>  
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    android:layout_width="fill_parent"  
    android:layout_height="wrap_content"  
    android:orientation="vertical" >  
    <LinearLayout  
        android:orientation="vertical"  
        android:layout_width="fill_parent"  
        android:layout_height="wrap_content"  
         >  
        <TextView   
            android:id="@+id/tv"  
            android:layout_width="fill_parent"  
            android:layout_height="50dip"  
            android:textColor="#FCFCFC"  
            android:textSize="11pt"  
            android:gravity="center_vertical"  
            android:layout_marginLeft="10dip"  
            />   
    <ListView  
        android:id="@+id/lv"  
        android:layout_width="fill_parent"  
        android:layout_height="381dip"  
        android:cacheColorHint ="#00000000"  
         ></ListView>  
    </LinearLayout>  
    <RelativeLayout   
        android:layout_width="fill_parent"  
        android:layout_height="53dip"  
        android:orientation="horizontal"  
        >  
        <Button   
            android:id="@+id/selectall"  
            android:layout_width="80dip"      
            android:layout_height="50dip"  
            android:layout_marginLeft="20dip"  
            android:text="全选"  
            android:gravity="center"  
            />  
        <Button   
            android:id="@+id/inverseselect"  
            android:layout_width="80dip"      
            android:layout_height="50dip"  
            android:layout_marginLeft="118dip"  
            android:text="反选"  
            android:gravity="center"  
            />  
        <Button   
            android:id="@+id/cancel"  
            android:layout_width="80dip"      
            android:layout_height="50dip"  
            android:layout_marginLeft="213dip"  
            android:text="取消已选"  
            android:gravity="center"  
            />  
    </RelativeLayout>  
</LinearLayout>  

ListView每个item的布局,listviewitem.xml：


这里需要注意的是，由于checkbox的点击事件优先级比listview的高，所以要添加Android:focusable="false"属性，使得checkbox初始的时候没有获取焦点。


另外这里是点击ListView的item控制checkbox的状态改变，也就是让item接收clik事件，所以需要加上android:focusableInTouchMode="false"这一属性。

<?xml version="1.0" encoding="utf-8"?>  
<RelativeLayout  xmlns:android="http://schemas.android.com/apk/res/android"  
    android:layout_width="fill_parent"  
    android:layout_height="55dip"  
    android:orientation="horizontal"  
    android:layout_marginTop="20dip"  
    >   
    <TextView   
        android:id="@+id/item_tv"  
        android:layout_width="267dip"  
        android:layout_height="40dip"  
        android:textSize="10pt"  
        android:gravity="center_vertical"  
        android:layout_marginLeft="10dip"  
        />  
    <CheckBox   
        android:id="@+id/item_cb"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:focusable="false"      
        android:focusableInTouchMode="false"      
        android:clickable="false"    
        android:layout_toRightOf="@id/item_tv"     
        android:layout_alignParentTop="true"  
        android:layout_marginRight="5dip"  
         
        />  
</RelativeLayout >  

ViewHolder类

package simtice.test.listview.viewholder;  
import Android.widget.CheckBox;  
import android.widget.TextView;  
  
public class ViewHolder {  
    public TextView tv = null;  
    public CheckBox cb = null;  
}  

为listview自定义适配器，该类为主Activity类MainActivity.java的内部类

public static class MyAdapter extends BaseAdapter {  
        public static HashMap<Integer, Boolean> isSelected;  
        private Context context = null;  
        private LayoutInflater inflater = null;  
        private List<HashMap<String, Object>> list = null;  
        private String keyString[] = null;  
        private String itemString = null; // 记录每个item中textview的值   
        private int idValue[] = null;// id值   
  
        public MyAdapter(Context context, List<HashMap<String, Object>> list,  
                int resource, String[] from, int[] to) {  
            this.context = context;  
            this.list = list;  
            keyString = new String[from.length];  
            idValue = new int[to.length];  
            System.arraycopy(from, 0, keyString, 0, from.length);  
            System.arraycopy(to, 0, idValue, 0, to.length);  
            inflater = LayoutInflater.from(context);  
            init();  
        }  
  
        // 初始化 设置所有checkbox都为未选择   
        public void init() {  
            isSelected = new HashMap<Integer, Boolean>();  
            for (int i = 0; i < list.size(); i++) {  
                isSelected.put(i, false);  
            }  
        }  
  
        @Override  
        public int getCount() {  
            return list.size();  
        }  
  
        @Override  
        public Object getItem(int arg0) {  
            return list.get(arg0);  
        }  
  
        @Override  
        public long getItemId(int arg0) {  
            return 0;  
        }  
  
        @Override  
        public View getView(int position, View view, ViewGroup arg2) {  
            ViewHolder holder = new ViewHolder();  
                 
                if (view == null) {  
                    view = inflater.inflate(R.layout.listviewitem, null);  
                }  
                holder.tv = (TextView) view.findViewById(R.id.item_tv);  
                holder.cb = (CheckBox) view.findViewById(R.id.item_cb);  
                view.setTag(holder);  
            } 
            HashMap<String, Object> map = list.get(position);  
            if (map != null) {  
                itemString = (String) map.get(keyString[0]);  
                holder.tv.setText(itemString);  
            }  
            holder.cb.setChecked(isSelected.get(position));  
            return view;  
        }  
  
    }  

最后，最重要的就是MainActivity.java中一些事件响应的处理

public class MainActivity extends Activity {  
    TextView tv = null;  
    ListView lv = null;  
    Button btn_selectAll = null;  
    Button btn_inverseSelect = null;  
    Button btn_calcel = null;  
    String name[] = { "G1", "G2", "G3", "G4", "G5", "G6", "G7", "G8", "G9",  
            "G10", "G11", "G12", "G13", "G14" };  
      
    ArrayList<String> listStr = null;  
    private List<HashMap<String, Object>> list = null;  
    private MyAdapter adapter;  
  
    @Override  
    public void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
        tv = (TextView) this.findViewById(R.id.tv);  
        lv = (ListView) this.findViewById(R.id.lv);  
        btn_selectAll = (Button) this.findViewById(R.id.selectall);  
        btn_inverseSelect = (Button) this.findViewById(R.id.inverseselect);  
        btn_calcel = (Button) this.findViewById(R.id.cancel);  
        showCheckBoxListView();  
          
        //全选   
        btn_selectAll.setOnClickListener(new OnClickListener(){  
            @Override  
            public void onClick(View arg0) {  
                listStr = new ArrayList<String>();  
                for(int i=0;i<list.size();i++){  
                    MyAdapter.isSelected.put(i,true);  
                    listStr.add(name[i]);  
                }  
                adapter.notifyDataSetChanged();//注意这一句必须加上，否则checkbox无法正常更新状态   
                tv.setText("已选中"+listStr.size()+"项");  
            }  
        });  
          
        //反选   
        btn_inverseSelect.setOnClickListener(new OnClickListener(){  
            @Override  
            public void onClick(View v) {  
                for(int i=0;i<list.size();i++){  
                    if(MyAdapter.isSelected.get(i)==false){  
                        MyAdapter.isSelected.put(i, true);  
                        listStr.add(name[i]);  
                    }  
                    else{  
                        MyAdapter.isSelected.put(i, false);  
                        listStr.remove(name[i]);  
                    }  
                }  
                adapter.notifyDataSetChanged();  
                tv.setText("已选中"+listStr.size()+"项");  
            }  
              
        });  
          
        //取消已选   
        btn_calcel.setOnClickListener(new OnClickListener(){  
            @Override  
            public void onClick(View v) {  
                for(int i=0;i<list.size();i++){  
                    if(MyAdapter.isSelected.get(i)==true){  
                        MyAdapter.isSelected.put(i, false);  
                        listStr.remove(name[i]);  
                    }  
                }  
                adapter.notifyDataSetChanged();  
                tv.setText("已选中"+listStr.size()+"项");  
            }  
              
        });  
    }  
  
    // 显示带有checkbox的listview   
    public void showCheckBoxListView() {  
        list = new ArrayList<HashMap<String, Object>>();  
        for (int i = 0; i < name.length; i++) {  
            HashMap<String, Object> map = new HashMap<String, Object>();  
            map.put("item_tv", name[i]);  
            map.put("item_cb", false);  
            list.add(map);  
  
            adapter = new MyAdapter(this, list, R.layout.listviewitem,  
                    new String[] { "item_tv", "item_cb" }, new int[] {  
                            R.id.item_tv, R.id.item_cb });  
            lv.setAdapter(adapter);  
            listStr = new ArrayList<String>();  
            lv.setOnItemClickListener(new OnItemClickListener() {  
  
                @Override  
                public void onItemClick(AdapterView<?> arg0, View view,  
                        int position, long arg3) {  
                    ViewHolder holder = (ViewHolder) view.getTag();  
                    holder.cb.toggle();// 在每次获取点击的item时改变checkbox的状态   
                    MyAdapter.isSelected.put(position, holder.cb.isChecked()); // 同时修改map的值保存状态   
                    if (holder.cb.isChecked() == true) {  
                        listStr.add(name[position]);  
                    } else {  
                        listStr.remove(name[position]);  
                    }  
                    tv.setText("已选中"+listStr.size()+"项");  
                }  
  
            });  
        }  
    }  
  
    //为listview自定义适配器内部类   
    public static class MyAdapter extends BaseAdapter {  
        ...  
    }  
}  

结果如下

只要代码不要复制错应该可以运行，我已经试过。