Question

我有一个Android应用程序，我有两个选项卡。我希望每当选项卡发生变化时。选择的选项卡应从头开始加载。我不希望在更改标签时显示任何以前的数据... 我尝试使用制表符更改侦听器但它没用。请建议我能做些什么。我是Android开发的新手

这是我的代码

解决

   package com.example.pms;

import android.app.AlertDialog;
import android.app.TabActivity;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.TabHost;
import android.widget.TabHost.OnTabChangeListener;
import android.widget.TextView;
import android.widget.TabHost.TabSpec;
import android.widget.Toast;


public class TabControl extends TabActivity 
{
    public static TabControl mTabControl;
    public static TextView textView;
    public static TabHost tabHost ;
    final Context context = this;

    @SuppressWarnings("deprecation")
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        Resources resources = getResources(); 
        TabHost tabHost = getTabHost(); 


          Bundle extras = getIntent().getExtras();
          String strEmployeeID="";

          TabSpec photospec = tabHost.newTabSpec("Hourly");
            // setting Title and Icon for the Tab
            photospec.setIndicator("Hourly Entry");

              if (extras != null)
              {

                  String value = extras.getString("new_variable_name");
//                Toast.makeText(getBaseContext(),  value, Toast.LENGTH_LONG).show();
                  strEmployeeID = value;
              }


             Intent photosIntent = new Intent(getApplicationContext(), HourlyEntry.class);
             photosIntent.putExtra("new_variable_name",strEmployeeID);
             photospec.setContent(photosIntent);



             TabSpec photospec1 = tabHost.newTabSpec("Leave");
                // setting Title and Icon for the Tab
                photospec1.setIndicator("Leave App");

                  if (extras != null)
                  {

                      String value = extras.getString("new_variable_name");
//                    Toast.makeText(getBaseContext(),  value, Toast.LENGTH_LONG).show();
                      strEmployeeID = value;
                  }


                 Intent photosIntent1 = new Intent(getApplicationContext(), LeaveApp.class);
                 photosIntent1.putExtra("new_variable_name",strEmployeeID);
                 photospec1.setContent(photosIntent1);


        tabHost.addTab(photospec);
        tabHost.addTab(photospec1);



        tabHost.setCurrentTab(0);



    }

       @Override
       public boolean onKeyDown(int keyCode, KeyEvent event) {
           if ((keyCode == KeyEvent.KEYCODE_BACK)) {
               AlertDialog.Builder alertbox = new AlertDialog.Builder(TabControl.this);

               alertbox.setTitle("You Want To Sign Out ?");
               alertbox.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface arg0, int arg1) { 
                      // finish used for destroyed activity

                       signout();
                   }
               });

               alertbox.setNegativeButton("No", new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface arg0, int arg1) {
                           // Nothing will be happened when clicked on no button 
                           // of Dialog     
                 }
               });

               alertbox.show();
           }
           return super.onKeyDown(keyCode, event);
       }


       public void signout()
       {
           Intent i = new Intent(getApplicationContext(), MainActivity.class);

           startActivity(i); 
       }
}

Answer 1

定义 photospec，photospec1 全球范围内：

public class TabControl extends TabActivity 
{

TabSpec photospec,photospec1;
.........
..........
}

或移动此代码

 tabHost.setOnTabChangedListener(new OnTabChangeListener() {


            public void onTabChanged(String tabId) {    
                   if(photospec.equals(tabId)) {
                        //destroy earth
                    }
                    if(photospec1.equals(tabId)) {
                        //destroy mars
                    }




            }
        });

onCreate(.......)

结束时

标签更改侦听器无法正常工作

1 个答案: