как обновить ListView на фрагменте

Question

мне нужна ваша помощь

У меня есть ListView (BaseAdapter) (я заполнить его с SQLite) на фрагменте, этот фрагмент на PageViewer с Размах. Кроме того, есть кнопка на ActionBar, когда я нажимаю на кнопку, это загружает данные (внешний SQLServer) и я синхронизую с SQLite.

image

Мой вопрос:

Как при нажатии на кнопку Актуализировать ListView/обновить визуально на активности?

Answer 1

его простой, поскольку вы можете установить адаптер для списка на щелчок кнопки загрузки данных и вызвать метод notifydatasetchanged для адаптера.

package com.example.alarmapp2; 

import java.text.SimpleDateFormat; 
import java.util.Calendar; 

import android.annotation.SuppressLint; 
import android.app.AlarmManager; 
import android.app.AlertDialog; 
import android.app.DatePickerDialog; 
import android.app.DatePickerDialog.OnDateSetListener; 
import android.app.PendingIntent; 
import android.app.TimePickerDialog; 
import android.app.TimePickerDialog.OnTimeSetListener; 
import android.content.Context; 
import android.content.Intent; 
import android.os.Bundle; 
import android.support.v7.app.ActionBarActivity; 
import android.util.Log; 
import android.view.LayoutInflater; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.view.WindowManager; 
import android.widget.Button; 
import android.widget.DatePicker; 
import android.widget.EditText; 
import android.widget.ImageView; 
import android.widget.ListView; 
import android.widget.TextView; 
import android.widget.TimePicker; 
import android.widget.Toast; 

@SuppressLint("SimpleDateFormat") 
public class MainActivity extends ActionBarActivity implements OnClickListener { 
    private ImageView addButton; 
    private TextView tvDate; 
    private TimePicker tvTime; 
    private EditText message; 
    private Button save, cancel; 
    private DataBaseHelper dbhelper; 
    private ListView alarmListView; 
    private PendingIntent pendingIntent; 
    private AlarmManager manager; 
    private static MainActivity inst; 
    public static MainActivity instance() { 
     return inst; 
    } 

    @Override 
    public void onStart() { 
     super.onStart(); 
     inst = this; 
    } 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     dbhelper = new DataBaseHelper(this); 
     alarmListView= (ListView) findViewById(R.id.alarm_list); 
     addButton = (ImageView) findViewById(R.id.addButton); 
     addButton.setOnClickListener(this); 
     manager = (AlarmManager) getSystemService(ALARM_SERVICE); 
     //setting data to list view 
     addListDetails(); 
    } 
    @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; 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     // Handle action bar item clicks here. The action bar will 
     // automatically handle clicks on the Home/Up button, so long 
     // as you specify a parent activity in AndroidManifest.xml. 
     int id = item.getItemId(); 
     if (id == R.id.action_settings) { 
      return true; 
     } 
     return super.onOptionsItemSelected(item); 
    } 

    @SuppressLint("InflateParams") 
    @Override 
    public void onClick(View v) { 
     switch (v.getId()) { 
     case R.id.addButton: 
      AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this); 
      LayoutInflater layoutInflater = LayoutInflater.from(this); 
      // setting layout view 
      View promptView = layoutInflater.inflate(R.layout.alaram_popup, null, false); 
      alertDialogBuilder.setView(promptView); 
      tvDate = (TextView) promptView.findViewById(R.id.select_date); 
      tvDate.setOnClickListener(this); 
      tvTime = (TimePicker) promptView.findViewById(R.id.select_time); 
      /*tvTime.setOnClickListener(this);*/ 
      tvTime.setIs24HourView(true); 
      message = (EditText) promptView.findViewById(R.id.message); 
      save = (Button) promptView.findViewById(R.id.save); 
      cancel = (Button) promptView.findViewById(R.id.cancel); 
      alertDialogBuilder.setCancelable(true); 
      final AlertDialog alertDialog = alertDialogBuilder.create(); 
      alertDialog.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND); 
      alertDialog.show(); 
      save.setOnClickListener(new View.OnClickListener() { 

       @Override 
       public void onClick(View v) { 
        if (tvDate.getText().toString().length() == 0) { 
         tvDate.setError("Select Date"); 
        } /*else if (tvTime.getText().toString().length() == 0) { 
         tvTime.setError("Select Date"); 
        } */else if (message.getText().toString().length() == 0) { 
         message.setError("Select Date"); 
        } else { 
         String timeMin=""; 
         dbhelper=new DataBaseHelper(MainActivity.this); 
         if(tvTime.getCurrentMinute()<10){ 
          timeMin="0"+tvTime.getCurrentMinute(); 
         }else{ 
          timeMin=""+tvTime.getCurrentMinute(); 
         } 
         AlarmDoa doa = new AlarmDoa(); 
         doa.setDate(tvDate.getText().toString()); 
         doa.setTime(tvTime.getCurrentHour()+":"+timeMin); 
         doa.setMessage(message.getText().toString()); 
         long Status=dbhelper.addalarm(doa); 
         alertDialog.dismiss(); 
         if(Status!=0){ 
          //settin data on click of button 
          addListDetails(); 
          Toast.makeText(MainActivity.this, "Alarm Set", Toast.LENGTH_SHORT).show(); 
          setAlarm(tvDate.getText().toString(),tvTime.getCurrentHour()+":"+tvTime.getCurrentMinute(),message.getText().toString()); 
         }else{ 
          Toast.makeText(MainActivity.this, "Alarm Can't Be Set", Toast.LENGTH_SHORT).show(); 
         } 
        } 
       } 
      }); 
      cancel.setOnClickListener(new View.OnClickListener() { 

       @Override 
       public void onClick(View v) { 
        alertDialog.cancel(); 
       } 
      }); 
      break; 
     case R.id.select_date: 
      Calendar c = Calendar.getInstance(); 
      SimpleDateFormat df = new SimpleDateFormat("dd-MM-yyyy"); 
      String[] data = df.format(c.getTime()).split("-"); 
      DatePickerDialog datePicker = new DatePickerDialog(this, onDate, Integer.parseInt(data[0]), 
        Integer.parseInt(data[1]), Integer.parseInt(data[2])); 
      datePicker.getDatePicker().setMinDate(System.currentTimeMillis()); 
      datePicker.show(); 
      break; 
     case R.id.select_time: 
      Calendar c1 = Calendar.getInstance(); 

      TimePickerDialog timePicker=new TimePickerDialog(this, onTime, c1.get(Calendar.HOUR_OF_DAY), c1.get(Calendar.MINUTE), false); 
      timePicker.show(); 
      break; 
     } 
    } 

    protected void setAlarm(String date, String time, String msg) { 
     manager=(AlarmManager)getSystemService(Context.ALARM_SERVICE); 
     Intent alarmIntent = new Intent(MainActivity.this, AlarmReceiver.class); 
     alarmIntent.putExtra("date", ""+date); 
     alarmIntent.putExtra("time", ""+time); 
     alarmIntent.putExtra("msg", ""+msg); 
     pendingIntent = PendingIntent.getBroadcast(MainActivity.this, 0, alarmIntent, 0); 
     String[] data=time.split(":"); 
     Calendar calendar=Calendar.getInstance(); 
     calendar.set(Calendar.HOUR_OF_DAY,Integer.parseInt(data[0])); 
     calendar.set(Calendar.MINUTE, Integer.parseInt(data[1])); 
     Log.d("calendar.getTimeInMillis()", ""+calendar.getTimeInMillis()); 
     Log.d("System", ""+calendar.getTime()); 
     manager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent); 
     Toast.makeText(this, "ALarm Set", Toast.LENGTH_SHORT).show(); 
    } 

    OnDateSetListener onDate = new OnDateSetListener() { 
     @Override 
     public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) { 
      String month=""; 
      if(monthOfYear<9){ 
       month= "0"+String.valueOf(monthOfYear+1); 
      }else{ 
       month=String.valueOf(monthOfYear+1); 
      } 
      tvDate.setText(pad(dayOfMonth)+ "-" + month+ "-" + String.valueOf(year)); 

     } 
    }; 
    OnTimeSetListener onTime= new OnTimeSetListener() { 
     @Override 
     public void onTimeSet(TimePicker view, int hourOfDay, int minute) { 
      //tvTime.setText(pad(hourOfDay) + ":" + pad(minute)); 
     } 
    }; 
    private static String pad(int c) { 
     if (c >= 10) 
      return String.valueOf(c); 
     else 
      return "0" + String.valueOf(c); 
    } 

    private void addListDetails() { 
     dbhelper=new DataBaseHelper(MainActivity.this); 
     AlarmAdapter adapter= new AlarmAdapter(MainActivity.this, dbhelper.getAlarmList()); 
     adapter.notifyDataSetChanged(); 
     alarmListView.setAdapter(adapter); 
    } 
}