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。