Question

我是Android开发的新手，我在may app中有一个Listview，Listview中填充了来自Sqlite数据库的数据。我想在这个listview＆amp;上使用复选框。删除所选项目。我想从Sqlite Db确实清除选定的数据行。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SMS，如下所示：` if（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();`

然后按如下方式存储在SQlite DB中：

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中成功检索到了。

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();

// adapter.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帖子，但现在我想使用复选框从listview中删除一些短信有什么有用的教程吗？

Answer 1

试试这个

从列表视图中删除项目的代码

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

然后使用Query从Sqite数据库中删除数据

Answer 2

小小的提示可以提供帮助。由于您拥有数据，因此请记录标记的项目。存放他们的ID。一旦用户点击完成或您拥有的任何按钮，运行一个SQL查询，删除带有ID的记录。然后调用列表视图的notifyDataSetChanged。由于它的光标存在notifyDataSetChanged可能无法正常工作的变化，因此再次重新填充光标。

请参阅Refresh ListView和this

Answer 3

如果你在问题中成功删除了数据库中的数据，而不是使用listview的notifydatasetchanged方法用新数据重新加载listview。

Answer 4

对于自定义适配器，请将列表项行xml用作：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
     >

    <TextView

        android:id="@+id/data"
        android:padding="10dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
         />

    <CheckBox
        android:id="@+id/checkbox"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@+id/data"
        android:checked="false" />

</RelativeLayout>

并在自定义适配器java类

中

public class CustomAdapter extends BaseAdapter{

    ArrayList<String> mlistdata;
    private LayoutInflater layoutinflater;
    private Context mContext;
    public CustomAdapter(Context context,ArrayList<String> elements)
    {
        mlistdata = elements;
        layoutinflater=LayoutInflater.from(context);
        mContext=context;

    }
    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return mlistdata.size();
    }

    @Override
    public Object getItem(int arg0) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public long getItemId(int arg0) {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public View getView(final int arg0, View convertview, ViewGroup arg2) {
        // TODO Auto-generated method stub
        final ViewHolder holder;
        if(convertview==null)
        {
            holder = new ViewHolder();
            convertview = layoutinflater.inflate(R.layout.gallery_items, null);
            holder.txt=(TextView)convertview.findViewById(R.id.data);
            holder.cb=(CheckBox)convertview.findViewById(R.id.checkbox);
            convertview.setTag(holder);
        }
        else{
            holder=(ViewHolder)convertview.getTag();
        }
        holder.txt.setText((mlistdata.get(arg0)).toString());

    holder.cb.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            if(holder.cb.isChecked())
            {
            //database related operation
         }
          else
        {
        //database related operation
         }
            }

    });


    return convertview;
}
static class ViewHolder 
{
    TextView txt;
    CheckBox cb;
}

Answer 5

COM / nhaarman / ListViewAnimations。非常实用..你可以在https://play.google.com/store/apps/details?id=com.haarman.listviewanimations

看到演示

Answer 6

尝试此解决方案here

在EmployeeAdapter.java中，您将检查并取消选中dataList，并在此文件中编写一个方法getDataList();。

示例：

public List<employeemodel> getDataList(){
    return employeeData;
}

使用yourAdapter.getDataList();

在您的活动中使用此方法

获取datalist后执行删除操作并将新dataList设置为适配器并调用yourListView.notifyDatasetChange();。

Answer 7

自定义适配器和 notifyDataSetChanged()

从Listview中删除数据

7 个答案: