android - 从 ListView 中删除数据

Question

我是 Android 开发的新手，我在可能的应用程序中有一个 Listview，Listview 填充了来自 Sqlite 数据库的数据。我想在此 ListView 上使用复选框并删除所选项目。我确实想从 Sqlite Db 中清除选定的数据行。任何有用的帮助将不胜感激。

首先，我在我的应用程序中检索了短信，如下所示:` 如果( bundle != null){

            //—retrieve the SMS message received—
            Object messages[] = (Object[]) bundle.get("pdus");
            SmsMessage smsMessage[] = new SmsMessage[messages.length];

            for (int n = 0; n < messages.length; n++) {
                smsMessage[n] = SmsMessage.createFromPdu((byte[]) messages[n]);
                timestamp = smsMessage[n].getTimestampMillis();

                number = smsMessage[n].getOriginatingAddress();
                body += smsMessage[n].getDisplayMessageBody();
                abortBroadcast();
                blockMessage(context);
            } // end for loop
        } // bundle is null

    } catch (Exception e) {
        Log.e("SmsReceiver", "Exception smsReceiver" +e);

    }
}
private void blockMessage(Context context) {

    // instantiate DbMNager object to insert sms in database
    //formating receiving time:
    //SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-hh.mm.ss");
    SimpleDateFormat formatter = new SimpleDateFormat("EEEE, MMMM d  HH:mm:ss a");
    String formatedTime = formatter.format(timestamp);
    DBmanager= new DbManager(context);
    DBmanager.open();
    DBmanager.Insert_sms_data(formatedTime ,number,body);
    DBmanager.close();`

然后存储在SQlite DB中如下:

public void Insert_sms_data(String formatedTime, String number, String body){
    try{

        SQLiteDatabase DB = this.getWritableDatabase(); 
        ContentValues cv = new ContentValues();
        cv.put(SMS_Time, formatedTime);
        cv.put(PHONE_NUMBER, number);
        cv.put(MESSAGE_BODY, body);
        DB.insert(TABLE_SMS, null, cv);
        DB.close();

    }
    catch(Exception ex)
    {
        Log.e("ERROR in insertion", ex.toString());
    }

}

public Cursor Return_All(){

    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cur = db.rawQuery("SELECT * FROM "+"SMS_TABLE", null);
    return cur;

}
// Clear all messaged
public void ClearAll(){
    SQLiteDatabase db = this .getWritableDatabase();
    db.delete(TABLE_SMS, null, null);
    db.close();
}

之后在我的 ListView Activity 中成功检索。

public class MainActivity extends Activity {
ListView listViewSMS;
Context context;
DbManager manager;
Button btn_clearall;
Cursor cursor;
SimpleCursorAdapter adapter;
//array from is the column name in your cursor where you're getting the data 

String[] from = new String[]{"Phone_number","Message_body","Time"};
//array toIDs contains the id of textViews


int[] toIDs = new int[]{R.id.textViewSMSSender,R.id.textViewMessageBody,R.id.textViewMSMStime};
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.listview_activity_main);
    context=this;
    //get the ListView Reference
    try{
        listViewSMS=(ListView)findViewById(R.id.listViewSMS);
        listViewSMS.setChoiceMode(listViewSMS.CHOICE_MODE_MULTIPLE);

        manager = new DbManager(context);
        cursor = manager.Return_All();

        SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.listview_each_item, cursor, from, toIDs);
        listViewSMS.setAdapter(adapter);
        adapter.notifyDataSetChanged();
        //refreshCursor();

        listViewSMS.setOnItemClickListener(new OnItemClickListener(){

            @Override
            public void onItemClick(AdapterView<?> arg0, View v, int position,
                    long arg3) {

                int itemId = Integer.valueOf(String.valueOf(position));
                cursor.moveToPosition(itemId);
                int messageId = cursor.getInt(0);
                deleteMessage(messageId);

                                    Toast.makeText(getApplicationContext(), "current position"+itemId, Toast.LENGTH_LONG).show();
                                    TextView tv_SMSSenderNumber=(TextView)v.findViewById(R.id.textViewSMSSender);
                                    TextView tv_SMSBody=(TextView)v.findViewById(R.id.textViewMessageBody);
                                    TextView tv_SMSTime=(TextView)v.findViewById(R.id.textViewMSMStime);
                                    String smsSender=tv_SMSSenderNumber.getText().toString();
                                    String smsBody= tv_SMSBody.getText().toString();
                                    String smsTime= tv_SMSTime.getText().toString();    
            }

        });

    }

    catch(Exception ex){
        Log.e("ERROR!!", ex.toString());
    }


    btn_clearall = (Button)findViewById(R.id.btn_Delall);
    btn_clearall.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            clearMessages(); 
            //refreshCursor();

//适配器.notifyDataSetChanged();

        }
    });

    CheckBox cb_sms_lv = (CheckBox)findViewById(R.id.cb_smslist);


}

protected void clearMessages() {
    new AlertDialog.Builder(MainActivity.this).setIcon(
            android.R.drawable.ic_dialog_alert).setTitle(R.string.delete)
            .setMessage(getString(R.string.clear_message_confirm))
            .setPositiveButton(R.string.delete,
                    new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface di, int i) {
                    manager = new DbManager(
                            context);
                    manager.open();
                    manager.ClearAll();
                    manager.close();
                    refreshCursor();
                }
            }).setNegativeButton(R.string.cancel,
                    new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface di, int i) {
                }
            }).show();
}

private void deleteMessage(final int messageId){
    new AlertDialog.Builder(MainActivity.this).setIcon(
            android.R.drawable.ic_dialog_alert).setTitle(R.string.delete)
            .setMessage(getString(R.string.delete_message_confirm))
            .setPositiveButton(R.string.delete,
                    new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface di, int i) {
                    manager = new DbManager(
                            context);
                    manager.open();
                    manager.deleteMessage(messageId);
                    manager.close();
                    refreshCursor();
                }
            }).setNegativeButton(R.string.cancel,
                    new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface di, int i) {
                }
            }).show();
}

public void refreshCursor() {
    manager = new DbManager(context);
    manager.open();
    cursor = manager.Return_All();

    SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.listview_each_item, cursor, from, toIDs);
    listViewSMS.setAdapter(adapter);
    manager.close();

}



@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

我可以成功删除整个线程，但现在我想使用复选框从 ListView 中删除一些短信请问有什么有用的教程吗？

Answer 1

试试这个

从 ListView 中删除项目的代码

int index = Integer.parseInt(position+"");
                ArrayList.remove(index);
                notifyDataSetChanged();

然后使用Query从Sqite数据库中删除数据