Kann einen Artikel aus sharedPreferences nicht finden

Question

Ich versuche, ein Element aus der Taskliste zu löschen, die mit sharedPreferences verbunden ist. Ich habe es geschafft, alle Elemente zu entfernen, aber das Problem ist, kann ich keinen Weg finden, einen Zähler zu verbinden, um ein einzelnes Element aus einer Liste mit einem Schalter zu löschen, und wenn dieser Schalter auf true ist, muss ich das Element aus der Liste nach Indexnummer entfernen .

public class TaskAdapter extends BaseAdapter { 
//transfer context 
Context context; 
//transfer user to use for shared preferences 
String userName; 
//create a list of tasks..... 
List<taskItem> myTasks; 
Calendar calendar = Calendar.getInstance(); 
PendingIntent pendingIntent; 
int pos; 

//constructor, for creating the adapter we need from the user context and userName 
public TaskAdapter(Context context, String userName) { 
    this.context = context; 
    this.userName = userName; 
    //go to user shared preferences and fill the list 
    getData(); 
    notifyDataSetChanged(); 

} 
//how many item to display 
@Override 
public int getCount() { 
    //return the myTasks size.... 
    return myTasks.size(); 
} 

//return a specific item by index 
@Override 
public Object getItem(int i) { 
    return myTasks.get(i); 
} 

//return index number 
@Override 
public long getItemId(int i) { 
    return i; 
} 

//create our view 
@Override 
public View getView(final int index, final View view, ViewGroup viewGroup) { 
    //inflate the view inside view object -> viewInflated 
    final View viewInflated = LayoutInflater.from(context).inflate(R.layout.task_item, null, false); 
    //set our inflated view behavior 

    //set pointer for our inflated view 

    //set pointer for task name.... 
    final TextView txtTaskName = (TextView) viewInflated.findViewById(R.id.taskName); 
    //set pointer for taskInfo 
    final TextView txtTaskInfo = (TextView) viewInflated.findViewById(R.id.taskInfo); 
    //set pointer for task status.... 
    final Switch swTask = (Switch) viewInflated.findViewById(taskDone); 

    //set task name, by the index of my myTasks collection 
    txtTaskName.setText(myTasks.get(index).taskName); 
    //set task info, by index of myTasks collection 
    txtTaskInfo.setText(myTasks.get(index).taskInfo); 
    //set task status , switch is getting true/false 
    swTask.setChecked(myTasks.get(index).taskStatus); 

    //show date and time dialog 
    final ImageView dtPicker = (ImageView) viewInflated.findViewById(R.id.imgTime); 
    dtPicker.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      final AlertDialog.Builder ad = new AlertDialog.Builder(context); 
      final AlertDialog aDialog = ad.create(); 
      final LinearLayout adLayout = new LinearLayout(context); 
      adLayout.setOrientation(LinearLayout.VERTICAL); 
      TextView txtTime = new TextView(context); 
      txtTime.setText("Choose time"); 
      adLayout.addView(txtTime); 

      final TimePicker tp = new TimePicker(context); 
      adLayout.addView(tp); 
      final DatePicker dp = new DatePicker(context); 
      tp.setVisibility(View.GONE); 
      adLayout.addView(dp); 


      final Button btnNext = new Button(context); 
      btnNext.setText("Next>"); 
      adLayout.addView(btnNext); 
      btnNext.setGravity(1); 

      Button btnCancel = new Button(context); 
      btnCancel.setText("Cancel"); 
      adLayout.addView(btnCancel); 
      btnCancel.setGravity(1); 


      btnCancel.setOnClickListener(new View.OnClickListener() { 
       @Override 
       public void onClick(View v) { 
        aDialog.cancel(); 
       } 
      }); 
      btnNext.setOnClickListener(new View.OnClickListener() { 
       @Override 
       public void onClick(View view) { 
        final int hour = tp.getHour(); 
        final int min = tp.getMinute(); 

        final String myHour = String.valueOf(hour); 
        final String myMin = String.valueOf(min); 


        calendar.set(Calendar.MONTH, dp.getMonth()); 
        calendar.set(Calendar.YEAR, dp.getYear()); 
        calendar.set(Calendar.DAY_OF_MONTH, dp.getDayOfMonth()); 
        dp.setVisibility(View.GONE); 
        tp.setVisibility(View.VISIBLE); 
        btnNext.setText("Finish"); 
        btnNext.setOnClickListener(new View.OnClickListener() { 
         @Override 
         public void onClick(View v) { 
          AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); 
          calendar.set(Calendar.HOUR_OF_DAY, tp.getHour()); 
          calendar.set(Calendar.MINUTE, tp.getMinute()); 
          Intent my_intent = new Intent(context, RingtonePlayingService.class); 
          pendingIntent = PendingIntent.getService(context, 0, my_intent, PendingIntent.FLAG_UPDATE_CURRENT); 
          alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent); 
          if(hour > 12){ 
           String myHour = String.valueOf(hour - 12); 
          } 

          if(min < 10) 
          { 
           String myMin = "0"+String.valueOf(min); 
          } 

          Toast.makeText(context, "Set for- "+tp.getHour()+":"+tp.getMinute() , Toast.LENGTH_LONG).show(); 
          aDialog.cancel(); 
         } 
        }); 
       } 
      }); 
      aDialog.setView(adLayout); 
      aDialog.show(); 
     } 
    }); 

    //create listener event, when switch is pressed 
    swTask.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      //we using utlShared to update task status 
      //create instance of utlShared 
      utlShared myShared = new utlShared(context); 
      //calling method of task, and giving userName(shared preferences, taskName, taskStatus) 
      myShared.task(userName, txtTaskName.getText().toString(), txtTaskInfo.getText().toString(), swTask.isChecked()); 
      //we sending a message to the user, and inform him/her about the change 
      Toast.makeText(context, swTask.isChecked() ? "Task done" : "Task undone", Toast.LENGTH_SHORT).show(); 

     } 
    }); 

    //return the view with the behavior..... 
    return viewInflated; 
} 

private void getData() { 
    //go to specific shared preferences by user name..... 
    SharedPreferences taskPref = context.getSharedPreferences(userName, context.MODE_PRIVATE); 
    //create instance of our myTasks list 
    myTasks = new ArrayList<>(); 


     Map<String, ?> tasks = taskPref.getAll(); 
     for (Map.Entry<String, ?> oneTask : tasks.entrySet()) { 
      //insert task to list by Key and Value, we check if value is equal to 1, becuase 1=true 0=false 
      for(int pos=0 ; pos<myTasks.size() ; pos++){ 
       myTasks.get(pos); 
      } 
      String[] str = oneTask.getValue().toString().split(","); 
      myTasks.add(new taskItem(str[0], str[1], str[2].equals("1"))); 
     } 

} 

}

Und meine utlShared Klasse ist

public class utlShared { 

//context to use later 

Context context; 
//declatrtion of shared preferences object 
private SharedPreferences userPref; 
//declaration of shared preferences editor 
private SharedPreferences.Editor editor; 



public utlShared() {} 

public utlShared(Context context) 
{ 
    //get context to use it 
    this.context=context; 
    //declaretion of shared preferences with file name and file mode (private,public) 
    userPref=context.getSharedPreferences("users",Context.MODE_PRIVATE); 
    //declaration of editor 
    editor=userPref.edit(); 


} 

//get user and password 
public void addUser(String userName, String password) 
{ 

    //stores in the phone device under data\data\package name 
    //put in shared preferences user name and password 
    editor.putString(userName,password); 
    //commit (save/apply) the changes. 
    editor.commit(); 
} 


public boolean checkUser(String userName) 
{ 
    //get name by key->userName 
    String checkString = userPref.getString(userName,"na"); 
    //print to logcat a custom message..... 
    Log.e("checkUser", "checkUser: "+checkString); 
    //check if userName equals to responded data, if it's na, we don't have the user... 
    return !checkString.equals("na"); 


} 

public boolean checkUserPassword(String userName, String userPassword) 
{ 
    String checkString = userPref.getString(userName,"na"); 
    return checkString.equals(userPassword); 
} 

public void task(String userName,String taskName,String taskInfo, boolean taskDone) 
{ 
    //pointer to user task shared preferences 
    SharedPreferences taskPref=context.getSharedPreferences(userName, Context.MODE_PRIVATE); 
    //create editor to change the specific shared preferences 
    SharedPreferences.Editor taskEditor=taskPref.edit(); 

    //add new task -> if true write 1 else write 0 
    if(!taskDone){ 
     String myData = taskName+","+taskInfo+","+(taskDone?"1":"0"); 
     taskEditor.putString(taskName,myData); 
     //apply the changes 
     taskEditor.commit(); 
    } 


} 
public void clearTasks(String userName, String taskName, String taskInfo, boolean taskDone) 
{ 
    SharedPreferences taskPref=context.getSharedPreferences(userName, Context.MODE_PRIVATE); 
    SharedPreferences.Editor tskEditor=taskPref.edit(); 
     tskEditor.clear(); 
     tskEditor.commit(); 

} 

}

Diese Methode aus meiner Welcome Klasse aufgerufen wird, die

public class Welcome extends AppCompatActivity { 

String userName; 
Context context; 
utlShared myUtl; 
ListView taskList; 
String taskName; 
String taskInfo; 
boolean taskDone; 
AlarmManager alarmManager; 


@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_welcome); 
    setPointer(); 


} 

private void setPointer() 
{ 

    this.context=this; 
    userName=getIntent().getStringExtra("userName"); 
    myUtl = new utlShared(context); 
    taskList=(ListView)findViewById(R.id.taskList); 
    setListData(); 
    alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE); 
    Toast.makeText(Welcome.this, "welcome user:"+userName, Toast.LENGTH_SHORT).show(); 
    Button btnBack = (Button)findViewById(R.id.btnBack); 
    FloatingActionButton btnDelete=(FloatingActionButton)findViewById(R.id.btnDelete); 

    btnDelete.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      myUtl.clearTasks(userName, taskName, taskInfo, taskDone); 
      setListData(); 
     } 
    }); 

    btnBack.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      Intent intent = new Intent(context, MainActivity.class); 
      startActivity(intent); 
      finish(); 
     } 
    }); 



} 

private void setListData() { 
    final TaskAdapter adapter = new TaskAdapter(context, userName); 
    taskList.setAdapter(adapter); 
} 

public void addCustomTask(View view) 
{ 
    //create builder 
    AlertDialog.Builder builder = new AlertDialog.Builder(context); 
    //set title 
    builder.setTitle("Add new task!"); 


    //inflate view from layout ->custom layout,null,false as defualt values 
    View viewInflated= LayoutInflater.from(context).inflate(R.layout.dlg_new_task,null,false); 

    final EditText txtCustomLine = (EditText)viewInflated.findViewById(R.id.txtHLine); 
    final EditText txtCustomTask = (EditText)viewInflated.findViewById(R.id.txtTask); 

    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() { 
     @Override 
     public void onClick(DialogInterface dialogInterface, int i) { 
      dialogInterface.dismiss(); 
     } 
    }); 

    builder.setPositiveButton("Add task", new DialogInterface.OnClickListener() { 
     @Override 
     public void onClick(DialogInterface dialogInterface, int i) { 
      dialogInterface.dismiss(); 

      String myTaskCustom = txtCustomTask.getText().toString(); 
      String myTaskLine = txtCustomLine.getText().toString(); 
       myUtl.task(userName, myTaskCustom, myTaskLine, false); 
       setListData(); 
     } 
    }); 


    //display our inflated view in screen 
    builder.setView(viewInflated); 
    //show the dialog 
    builder.show(); 

} 

ist}

Sorry für den langen Code, aber ich habe so viel Zeit an diesem Problem verbracht und eine normale Art und Weise nur knapp sein Ziel zu finden, es zu beheben ...

Vielen Dank im Voraus Jungs, sehr geschätzt!

Answer 1

taskEditor.remove('item tag'); 
taskEditor.commit(); 

Answer 2

Raten Sie, meine Frage war nicht klar genug, aber ich habe einen Weg gefunden, dies zu tun.

if(!taskDone){ 
     String myData = taskName+","+taskInfo+","+(taskDone?"1":"0"); 
     taskEditor.putString(taskName,myData); 
     //apply the changes 
     taskEditor.commit(); 
    } 
    else 
    { 
     taskEditor.remove(taskName); 
     taskEditor.commit(); 
     adapter.notifyDataSetChanged(); 
    } 

Eventhough es ist nicht perfekt, weil ich die Ansicht aktualisieren kann, nachdem ich den Editor aktualisieren und erst nachdem ich die App meine letzten gelöschten Aufgaben verschwinden neu starten.

Prost und vielen Dank Jungs!