基於ListView和CheckBox實現多選和全選記錄的功能

應用開發中經常會有從數據庫中讀取數據顯示，然後選中多條、全部記錄並且刪除的需求。在做定製系統聯繫人的時候也遇到這樣的需求，下面寫個簡單的通過ListView和CheckBox實現多選、全選的例子。下面是具體的代碼，有問題請留言。代碼下載地址：MultiSelect.rar

MultiSelectActivity
[java] view plaincopy

/** 
 * @author [email protected]  
 * MultiSelectActivity 
 */  
public class MultiSelectActivity extends Activity implements OnClickListener,  
        OnItemClickListener {  
    private static final String TAG = "MultiSelectActivity";  
    private ListView contactsDelList;  
    private Button contactsDelBtn;  
    private Button contactsCancelBtn;  
    private CheckBox selectAll;  
    private Cursor cursor;  
    private ContactsDeleteAdapter contactsDeleteAdapter;  

    private static final String[] PROJECTION = new String[] { Contacts._ID,  
            Contacts.DISPLAY_NAME };  
    private static final int CONTACTS_ID_INDEX = 0;  
    private static final int DISPLAY_NAME_INDEX = 1;  
    private ContactsDeleteListItemViews holderViews;  

    private final class ContactsDeleteListItemViews {  
        TextView nameView;  
        CheckBox delCheckBox;  
    }  

    @Override  
    public void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.contacts_delete_activity);  
        contactsDelList = (ListView) findViewById(R.id.contacts_delete_list);  
        contactsDelBtn = (Button) findViewById(R.id.contacts_delete_btn);  
        contactsCancelBtn = (Button) findViewById(R.id.contacts_cancel_btn);  
        selectAll = (CheckBox) (findViewById(R.id.contacts_delete_list_header)  
                .findViewById(R.id.select_all));  
        contactsDelList.setOnItemClickListener(this);  
        contactsDelBtn.setOnClickListener(this);  
        contactsCancelBtn.setOnClickListener(this);  
        selectAll.setOnClickListener(this);  
    }  

    @Override  
    protected void onResume() {  
        super.onResume();  
        refreshData();  
    }  

    // 查詢數據庫  
    private void refreshData() {  
        cursor = getContentResolver().query(Contacts.CONTENT_URI, PROJECTION,  
                null, null, null);  
        contactsDeleteAdapter = new ContactsDeleteAdapter(this, cursor);  
        contactsDelList.setAdapter(contactsDeleteAdapter);  
    }  

    class ContactsDeleteAdapter extends BaseAdapter {  
        Cursor cur;  
        Map<Integer, Boolean> selectedMap;  
        HashSet<String> delContactsIdSet;  

        public ContactsDeleteAdapter(Context context, Cursor c) {  
            cur = c;  
            // 保存每條記錄是否被選中的狀態  
            selectedMap = new HashMap<Integer, Boolean>();  
            // 保存被選中記錄作數據庫表中的Id  
            delContactsIdSet = new HashSet<String>();  

            for (int i = 0; i < cur.getCount(); i++) {  
                selectedMap.put(i, false);  
            }  
        }  

        @Override  
        public View getView(int position, View convertView, ViewGroup parent) {  
            if (convertView == null) {  
                convertView = LayoutInflater.from(MultiSelectActivity.this)  
                        .inflate(R.layout.contacts_delete_list_item, null);  
                holderViews = new ContactsDeleteListItemViews();  
                holderViews.nameView = (TextView) convertView  
                        .findViewById(R.id.name);  
                holderViews.delCheckBox = (CheckBox) convertView  
                        .findViewById(R.id.delete_list_item);  
                convertView.setTag(holderViews);  
            }  
            cur.moveToPosition(position);  
            ContactsDeleteListItemViews views = (ContactsDeleteListItemViews) convertView  
                    .getTag();  
            final String name = cur.getString(DISPLAY_NAME_INDEX);  
            views.nameView.setText(name);  
            views.delCheckBox.setChecked(selectedMap.get(position));  
            // 保存記錄Id  
            if (selectedMap.get(position)) {  
                delContactsIdSet.add(String.valueOf(cur  
                        .getInt(CONTACTS_ID_INDEX)));  
            } else {  
                delContactsIdSet.remove(String.valueOf(cur  
                        .getInt(CONTACTS_ID_INDEX)));  
            }  
            return convertView;  
        }  

        @Override  
        public int getCount() {  
            return cur.getCount();  
        }  

        @Override  
        public Object getItem(int position) {  
            if (cur.moveToPosition(position)) {  
                return cur;  
            } else {  
                return null;  
            }  
        }  

        @Override  
        public long getItemId(int position) {  
            return position;  
        }  
    }  

    @Override  
    public void onClick(View v) {  
        switch (v.getId()) {  
        case R.id.select_all:  
            // 全選CheckBox的click事件處理  
            if (selectAll.isChecked()) {  
                for (int i = 0; i < contactsDeleteAdapter.getCount(); i++) {  
                    contactsDeleteAdapter.selectedMap.put(i, true);  
                    //click事件：全選checkbox被勾選則把所有的聯繫人ID添加到delContactsIdSet中  
                    contactsDeleteAdapter.cur.moveToPosition(i);  
                    contactsDeleteAdapter.delContactsIdSet.add(String  
                            .valueOf(contactsDeleteAdapter.cur  
                                    .getInt(CONTACTS_ID_INDEX)));  
                }  
                contactsDelBtn.setEnabled(true);  
            } else {  
                for (int i = 0; i < contactsDeleteAdapter.getCount(); i++) {  
                    contactsDeleteAdapter.selectedMap.put(i, false);  
                }  
                //click事件：全選checkbox被取消勾選則把delContactsIdSet清空  
                contactsDeleteAdapter.delContactsIdSet.clear();  
                contactsDelBtn.setEnabled(false);  
            }  
            contactsDeleteAdapter.notifyDataSetChanged();  
            break;  
        case R.id.contacts_delete_btn:  
            new AlertDialog.Builder(this).setTitle(  
                    R.string.clearConfirmation_title).setMessage(  
                    R.string.clearConfirmation).setNegativeButton(  
                    android.R.string.cancel, null).setPositiveButton(  
                    android.R.string.ok, new DialogInterface.OnClickListener() {  
                        @Override  
                        public void onClick(DialogInterface dialog, int which) {  
                            final ProgressDialog progressDialog = ProgressDialog  
                                    .show(  
                                            MultiSelectActivity.this,  
                                            getString(R.string.clearProgress_title),  
                                            "", true, false);  
                            final AsyncTask<Void, Void, Void> task = new AsyncTask<Void, Void, Void>() {  
                                @Override  
                                protected Void doInBackground(Void... params) {  
                                    // 刪除記錄事件處理（我這裏就不寫詳細的代碼了）  
                                    return null;  
                                }  

                                @Override  
                                protected void onPostExecute(Void result) {  
                                    progressDialog.dismiss();  
                                }  
                            };  
                            progressDialog.show();  
                            task.execute();  
                        }  
                    }).setCancelable(true).create().show();  
            break;  
        case R.id.contacts_cancel_btn:  
            // 取消事件處理  
            break;  
        }  
    }  

    @Override  
    public void onItemClick(AdapterView<?> arg0, View view, int position,  
            long id) {  
        Log.i(TAG, "onItemClick");  
        ContactsDeleteListItemViews views = (ContactsDeleteListItemViews) view  
                .getTag();  
        views.delCheckBox.toggle();  
        contactsDeleteAdapter.selectedMap.put(position, views.delCheckBox  
                .isChecked());  
        contactsDeleteAdapter.notifyDataSetChanged();  
        // 判斷是否有記錄沒被選中，以便修改全選CheckBox勾選狀態  
        if (contactsDeleteAdapter.selectedMap.containsValue(false)) {  
            selectAll.setChecked(false);  
        } else {  
            selectAll.setChecked(true);  
        }  
        // 判斷是否有記錄被選中，以便設置刪除按鈕是否可用  
        if (contactsDeleteAdapter.selectedMap.containsValue(true)) {  
            contactsDelBtn.setEnabled(true);  
        } else {  
            contactsDelBtn.setEnabled(false);  
        }  
    }  
}  

佈局文件：contacts_delete_activity.xml
[html] view plaincopy

<?xml version="1.0" encoding="utf-8"?>  
<!--  
    [email protected]  
    This layout of delete contacts.  
-->  
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    android:orientation="vertical" >  

    <include  
        android:id="@+id/contacts_delete_list_header"  
        layout="@layout/contacts_delete_list_header" />  

    <ListView  
        android:id="@+id/contacts_delete_list"  
        android:layout_width="match_parent"  
        android:layout_height="0dip"  
        android:layout_weight="1" />  

    <LinearLayout  
        style="@android:style/ButtonBar"  
        android:layout_width="match_parent"  
        android:layout_height="wrap_content"  
        android:orientation="horizontal" >  

        <Button  
            android:id="@+id/contacts_delete_btn"  
            android:layout_width="0dip"  
            android:layout_height="wrap_content"  
            android:layout_weight="1"  
            android:enabled="false"  
            android:text="@string/delete" />  

        <Button  
            android:id="@+id/contacts_cancel_btn"  
            android:layout_width="0dip"  
            android:layout_height="wrap_content"  
            android:layout_weight="1"  
            android:text="@string/cancel" />  
    </LinearLayout>  

</LinearLayout>