¿Cómo se actualiza el contenido de la ficha Cambio (Android)

Question

¿Alguien sabe cómo el contenido en las fichas se actualiza cuando se cambiaron a beeing? En otras palabras, cuando cambio una pestaña, quiero el contenido, en la pestaña estoy cambiando para refrescar o volver a crear.

Tengo este código como el TabActivity:

package com.example.HelloTabWidget;

import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.TabHost;
import android.widget.TabHost.OnTabChangeListener;

public class Bussruter extends TabActivity implements OnTabChangeListener {
 public void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.main);

     Resources res = getResources(); // Resource object to get Drawables
     TabHost tabHost = getTabHost();  // The activity TabHost
     TabHost.TabSpec spec;  // Resusable TabSpec for each tab
     Intent intent;  // Reusable Intent for each tab

     // Create an Intent to launch an Activity for the tab (to be reused)
     intent = new Intent().setClass(this, NedlastetBussruter.class);

     // Initialize a TabSpec for each tab and add it to the TabHost
     spec = tabHost.newTabSpec("Nedlastet bussruter").setIndicator("Nedlastet bussruter",
                       res.getDrawable(R.drawable.ic_tab_nedlastet))
                   .setContent(intent);
     tabHost.addTab(spec); 

     // Do the same for the other tabs
     intent = new Intent().setClass(this, AlleBussruter.class);
     spec = tabHost.newTabSpec("Alle bussruter").setIndicator("Alle bussruter",
                       res.getDrawable(R.drawable.ic_tab_alle))
                   .setContent(intent)
                   ;
     tabHost.addTab(spec);

     tabHost.setCurrentTab(2);
     tabHost.setOnTabChangedListener(this);
 }

 @Override
 public void onTabChanged(String tabId) {
  TabHost th = getTabHost();
  th.getCurrentTabView().destroyDrawingCache();//i know this is wrong :S
  th.getCurrentTabView().buildDrawingCache();//and this is also wrong....
 }
}

Ahora vamos a decir que yo estoy cambiando a la pestaña "NedlastetBussruter", que tiene el código:

package com.example.HelloTabWidget;

import java.io.File;
import java.util.ArrayList;

import android.app.AlertDialog;
import android.app.ListActivity;
import android.content.ActivityNotFoundException;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemLongClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;

public class NedlastetBussruter extends ListActivity {
 public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        String[] listName = this.getListNameNedlastet();
        setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, listName));

        ListView lv = getListView();
        lv.setTextFilterEnabled(true);
        if(!listName[0].equals("Ingen bussruter er lastet ned.")){
         lv.setOnItemClickListener(this.createClickListenerNedlastet());
         lv.setOnItemLongClickListener(this.createLongClickListener());
         lv.setClickable(true);
         lv.setLongClickable(true);
        }else{
         lv.setClickable(false);
         lv.setLongClickable(false);
        }
        /*new OnItemClickListener() {
          public void onItemClick(AdapterView<?> parent, View view,
              int position, long id) {
            // When clicked, show a toast with the TextView text
            Toast.makeText(getApplicationContext(), ((TextView) view).getText(),
                Toast.LENGTH_SHORT).show();
          }
        });*/
        /*TextView textview = new TextView(this);
        textview.setText("This is the Artists tab");
        setContentView(textview);*/
    }
 private OnItemLongClickListener createLongClickListener() {
  return 
  new OnItemLongClickListener() {
   public boolean onItemLongClick(AdapterView<?> parent, final View view,
        final int position, long id) {
    if(isAvailable(position)){
     try{
      new AlertDialog.Builder(parent.getContext())
      .setMessage("Vil du slette bussruten?")
         .setCancelable(false)
         .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
          public void onClick(DialogInterface dialog, int id) {

           deleteFile(view, position);
                 StorageHandler.availability[position] = false;
             }
         })
         .setNegativeButton("No", new DialogInterface.OnClickListener() {
          public void onClick(DialogInterface dialog, int id) {
           dialog.cancel();
             }
         })
         .show();
     }catch(Exception e){
      toastText("ERROR: "+e.getMessage(), Toast.LENGTH_LONG);
     }
     return true;
    }else return false;
   }
  };
 }
 private OnItemClickListener createClickListenerNedlastet(){
  return 
  new OnItemClickListener() {
   public void onItemClick(AdapterView<?> parent, View view,
       int position, long id){  

      boolean temp = StorageHandler.availability[position];
      if(temp == true){
       if(Environment.getExternalStorageState().equals(
         Environment.MEDIA_MOUNTED)){
        File file = new File(StorageHandler.sdcardUrl+ StorageHandler.uniqueBussFilename[position]);

                 if (file.exists()) {//open the file
                     Uri path = Uri.fromFile(file);
                     Intent intent = new Intent(Intent.ACTION_VIEW);
                     intent.setDataAndType(path, "application/pdf");
                     intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                     try {
                      startActivity(intent);
                     } 
                     catch (ActivityNotFoundException e) {
                      toastText("No Application Available for viewing PDF", Toast.LENGTH_LONG);
                     }
                 }else{
                  toastText("The file "+file.getAbsolutePath()+" was not found.", Toast.LENGTH_LONG);
                 }
       }else{
        toastText("sdkort er ikke tilgjengelig.", Toast.LENGTH_LONG);
       }
      }
   };
  };
 }
 private void toastText(String t, int l){
  final String text = t;
  final int length = l;
  Toast.makeText(getApplicationContext(), text, length).show();    

 }
 private void deleteFile(View view, int index){
  try{
   File f =  new File(StorageHandler.sdcardUrl + StorageHandler.uniqueBussFilename[index]);
   f.delete();
  }catch(Exception e){
   toastText("ERROR: "+e.getMessage(), Toast.LENGTH_LONG);
  }
 }
 private boolean isAvailable(int position){
  File f = new File(StorageHandler.sdcardUrl + StorageHandler.uniqueBussFilename[position]);
  if(f.exists()){
   return true;
  }
  return false;
 }
 private String[] getListNameNedlastet() {
  this.checkAvaliablePdfs();
  ArrayList<String> al = new ArrayList<String>();

  for(int i = 0;i<StorageHandler.uniqueId.length-1;i++){
    if(StorageHandler.availability[i]){
    //String br = bussRuter[i]; //used for debugging...
    al.add(StorageHandler.uniqueId[i] + " - " + StorageHandler.bussRuter[i]);
   }
  }
  String[] output = new String[al.size()];
  if(output.length == 0){
   output = new String[]{"Ingen bussruter er lastet ned."};
  }else{
   for(int i=0;i < al.size();i++){
     output[i] = al.get(i);
   }
  }
  return output;
 }
 private void checkAvaliablePdfs(){
  for(int i = 0;i<StorageHandler.uniqueBussFilename.length;i++){
   File f = new File(StorageHandler.sdcardUrl + StorageHandler.uniqueBussFilename[i]);
   if(f.exists()){
    StorageHandler.availability[i] = true;
   }
  }
 }
}

¿Cómo puedo hacer que la pestaña "nedlastet bussruter" recrear el contenido cada vez que se cambia a beeing? ¿hay un comando fácil disponibles?

Answer 1

Cuando las pestañas, se llama el método "onResume" (en la actividad, NedlastetBussruter). En el método puede "recarga" sus datos. Así que añadir la méthode onResume. También es posible que tenga que llamar yourAdapter.notifyDataSetChanged ();