实现类似下图功能:
代码如下:
activity_main.xml:
listviewitem.xml:
MainActivity.java:
public class MainActivity extends Activity { private ListView lv; private MyAdapter mAdapter; private ArrayListlist; private Button bt_selectall; private Button bt_cancel; private Button bt_deselectall; private int checkNum; // 记录选中的条目数量 private TextView tv_show;// 用于显示选中的条目数量 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); /* 实例化各个控件 */ lv = (ListView) findViewById(R.id.lv); bt_selectall = (Button) findViewById(R.id.bt_selectall); bt_cancel = (Button) findViewById(R.id.bt_cancleselectall); bt_deselectall = (Button) findViewById(R.id.bt_deselectall); tv_show = (TextView) findViewById(R.id.tv); list = new ArrayList (); // 为Adapter准备数据 initDate(); // 实例化自定义的MyAdapter mAdapter = new MyAdapter(list, this); // 绑定Adapter lv.setAdapter(mAdapter); // 全选按钮的回调接口 bt_selectall.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // 遍历list的长度,将MyAdapter中的map值全部设为true for (int i = 0; i < list.size(); i++) { MyAdapter.getIsSelected().put(i, true); } // 数量设为list的长度 checkNum = list.size(); // 刷新listview和TextView的显示 dataChanged(); } }); // 反选按钮的回调接口 bt_cancel.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // 遍历list的长度,将已选的设为未选,未选的设为已选 for (int i = 0; i < list.size(); i++) { if (MyAdapter.getIsSelected().get(i)) { MyAdapter.getIsSelected().put(i, false); checkNum--; } else { MyAdapter.getIsSelected().put(i, true); checkNum++; } } // 刷新listview和TextView的显示 dataChanged(); } }); // 取消按钮的回调接口 bt_deselectall.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // 遍历list的长度,将已选的按钮设为未选 for (int i = 0; i < list.size(); i++) { if (MyAdapter.getIsSelected().get(i)) { MyAdapter.getIsSelected().put(i, false); checkNum--;// 数量减1 } } // 刷新listview和TextView的显示 dataChanged(); } }); // 绑定listView的监听器 lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView arg0, View arg1, int arg2, long arg3) { // 取得ViewHolder对象,这样就省去了通过层层的findViewById去实例化我们需要的cb实例的步骤 ViewHolder holder = (ViewHolder) arg1.getTag(); // 改变CheckBox的状态 holder.cb.toggle(); // 将CheckBox的选中状况记录下来 MyAdapter.getIsSelected().put(arg2, holder.cb.isChecked()); // 调整选定条目 if (holder.cb.isChecked() == true) { checkNum++; } else { checkNum--; } // 用TextView显示 tv_show.setText("已选中" + checkNum + "项"); } }); } // 初始化数据 private void initDate() { for (int i = 0; i < 15; i++) { list.add("data" + " " + i); } ; } // 刷新listview和TextView的显示 private void dataChanged() { // 通知listView刷新 mAdapter.notifyDataSetChanged(); // TextView显示最新的选中数目 tv_show.setText("已选中" + checkNum + "项"); };}
MyAdapter.java:
public class MyAdapter extends BaseAdapter { // 填充数据的list private ArrayListlist; // 用来控制CheckBox的选中状况 private static HashMap isSelected; // 上下文 private Context context; // 用来导入布局 private LayoutInflater inflater = null; // 构造器 public MyAdapter(ArrayList list, Context context) { this.context = context; this.list = list; inflater = LayoutInflater.from(context); isSelected = new HashMap (); // 初始化数据 initDate(); } // 初始化isSelected的数据 private void initDate() { for (int i = 0; i < list.size(); i++) { getIsSelected().put(i, false); } } @Override public int getCount() { return list.size(); } @Override public Object getItem(int position) { return list.get(position); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder = null; if (convertView == null) { // 获得ViewHolder对象 holder = new ViewHolder(); // 导入布局并赋值给convertview convertView = inflater.inflate(R.layout.listviewitem, null); holder.tv = (TextView) convertView.findViewById(R.id.item_tv); holder.cb = (CheckBox) convertView.findViewById(R.id.item_cb); // 为view设置标签 convertView.setTag(holder); } else { // 取出holder holder = (ViewHolder) convertView.getTag(); } // 设置list中TextView的显示 holder.tv.setText(list.get(position)); // 根据isSelected来设置checkbox的选中状况 holder.cb.setChecked(getIsSelected().get(position)); return convertView; } public static HashMap getIsSelected() { return isSelected; } public static void setIsSelected(HashMap isSelected) { MyAdapter.isSelected = isSelected; } public static class ViewHolder { TextView tv; CheckBox cb; }}
ok!
扩展:以上复选框状态的变化是通过,private void dataChanged() {
// 通知listView刷新 mAdapter.notifyDataSetChanged(); // TextView显示最新的选中数目 tv_show.setText("已选中" + checkNum + "项"); };
实现的。也可以这样实现,不通过mAdapter.notifyDataSetChanged();
ListViewServerListAdapter.ListItemView lv = (ListViewServerListAdapter.ListItemView) view.getTag(); lv.cb.toggle(); ListViewServerListAdapter.isSelected.put(position, lv.cb.isChecked());