FragmentTransaction의 함수 "addToBackStack (String string)"을 사용하는 방법

Question

내 응용 프로그램에서 Tab을 따르려고합니다. 따라서 TabHost (세 조각 내)를 사용합니다. 탭 2 ~ 3에서, 휴대 전화에서 "뒤로"버튼을 클릭하면 활동성을 파괴하라는 메시지가 나타납니다.

"addToBackStack (String temp)"은 "onBackPressed"함수에서 뭔가를 수행하는 것을 준수 할 수 있습니까?

아래 코드는 제 코드입니다. ps : 이것은 내 첫 번째 질문입니다. 내 영어는 soso입니다. 죄송합니다.

package in.wptrafficanalyzer.navigationtabdemo; 
import android.app.Activity; 
import android.app.Fragment; 
import android.app.FragmentManager; 
import android.app.FragmentTransaction; 
import android.os.Bundle; 
import android.view.GestureDetector; 
import android.view.MotionEvent; 
import android.widget.TabHost; 
public class MainActivity extends Activity{ 

private static final int SWIPE_MIN_DISTANCE = 120; 
private static final int SWIPE_MAX_OFF_PATH = 250; 
private static final int SWIPE_THRESHOLD_VELOCITY = 200; 
private TabHost tHost; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    tHost = (TabHost) findViewById(R.id.tabhost1); 
    tHost.setup(); 

    TabHost.OnTabChangeListener tabChangeListener = new TabHost.OnTabChangeListener() 
    { 
     @Override 
     public void onTabChanged(String tabId) 
     { 
      FragmentManager fm = getFragmentManager(); 
      Fragment androidFragment = fm.findFragmentByTag("android"); 
      Fragment appleFragment = fm.findFragmentByTag("apple"); 
      Fragment wpFragment = fm.findFragmentByTag("wp"); 
      FragmentTransaction ft = fm.beginTransaction(); 

      if(androidFragment!=null) 
       ft.detach(androidFragment); 
      if(appleFragment!=null) 
       ft.detach(appleFragment); 
      if(wpFragment != null) 
       ft.detach(wpFragment); 
      /** If current tab is android */ 
      if(tabId.equalsIgnoreCase("tabAndroid")) 
      { 
       if(androidFragment==null)  
        /** Create AndroidFragment and adding to fragmenttransaction */ 
        ft.replace(R.id.realtabcontent, new AndroidFragment(), "android"); 
       else 
        /** Bring to the front, if already exists in the fragmenttransaction */ 
        ft.attach(androidFragment); 
       if(fm.getBackStackEntryCount() == 0) 
       { 
        ft.addToBackStack(null); 
       } 
      } 
      else if(tabId.equalsIgnoreCase("tabApple")) 
      { 
       /** If current tab is apple */ 
       if(appleFragment==null) 
        /** Create AppleFragment and adding to fragmenttransaction */ 
        ft.replace(R.id.realtabcontent,new AppleFragment(), "apple");      
       else 
        /** Bring to the front, if already exists in the fragmenttransaction */ 
        ft.attach(appleFragment); 
      } 
      else 
       if(wpFragment==null) 
        ft.replace(R.id.realtabcontent,new WPFragment(), "wp"); 
       else 
        ft.attach(wpFragment); 
      ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN); 
      ft.commit();     
     } 
    }; 
    /** Setting tabchangelistener for the tab */ 
    tHost.setOnTabChangedListener(tabChangeListener); 

    /** Defining tab builder for Andriod tab */ 
    TabHost.TabSpec tSpecAndroid = tHost.newTabSpec("tabAndroid"); 
    tSpecAndroid.setIndicator("Android",null);   
    tSpecAndroid.setContent(new DummyTabContent(getBaseContext())); 
    tHost.addTab(tSpecAndroid); 

    /** Defining tab builder for Apple tab */ 
    TabHost.TabSpec tSpecApple = tHost.newTabSpec("tabApple"); 
    tSpecApple.setIndicator("Apple",null);   
    tSpecApple.setContent(new DummyTabContent(getBaseContext())); 
    tHost.addTab(tSpecApple); 

    TabHost.TabSpec tSpecWp = tHost.newTabSpec("tabWp"); 
    tSpecWp.setIndicator("Wp",null);   
    tSpecWp.setContent(new DummyTabContent(getBaseContext())); 
    tHost.addTab(tSpecWp); 
} 
} 

Answer 1

당신이 이런 식으로 뭔가를 할 수 있습니다 : 당신의 스택이 비어 있지 않은 경우

@Override 
     public void onBackPressed() { 
      // TODO Auto-generated method stub 




     if (getSupportFragmentManager().getBackStackEntryCount() > 0) { 
        fragmentManager.popBackStack(null, 
           FragmentManager.POP_BACK_STACK_INCLUSIVE); 
       } 
     else{ 
     super.onBackPressed(); 
     } 

     } 

가 다시 버튼을 체크 비어 확인하고 비어 있으면