無法將WebViewFragment派生類添加到FragmentTransaction

Question

我正在使用ActionBarSherlock並實現選項卡式應用程序。每個選項卡表示一個只包含WebView的片段。我已經用從Fragment派生的對象實現了它。但是當我將其更改爲WebViewFragment時，我不能再將其添加到FragmentTransaction中。我想知道我是否輸入了正確的東西？下面的代碼：

import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentActivity; 
import android.support.v4.app.FragmentTransaction; 

import android.app.ProgressDialog; 
import android.content.Intent; 
import android.graphics.Bitmap; 
import android.net.Uri; 
import android.os.Bundle; 
import android.os.Handler; 
import android.os.Message; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.webkit.WebView; 
import android.webkit.WebViewClient; 
import android.webkit.WebViewFragment; 
import android.widget.TextView; 

public class WebTab1Fragment extends FragmentActivity { 
    int mStackLevel = 1; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.webtab1_layout); 


    if (savedInstanceState == null) { 
     // Do first time initialization -- add initial fragment. 
     MyWebvewFragment newFragment = MyWebviewFragment.newInstance(mStackLevel); 
     FragmentTransaction ft = getSupportFragmentManager().beginTransaction(); 
     ft.add(R.id.simple_fragment, newFragment).commit(); 

    } else { 
     mStackLevel = savedInstanceState.getInt("level"); 
    } 
} 

@Override 
public void onSaveInstanceState(Bundle outState) { 
    super.onSaveInstanceState(outState); 
    outState.putInt("level", mStackLevel); 
} 


void addFragmentToStack() { 
    mStackLevel++; 

    // Instantiate a new fragment. 
    MyWebviewFragment newFragment = MyWebviewFragment.newInstance(mStackLevel); 

    // Add the fragment to the activity, pushing this transaction 
    // on to the back stack. 
    FragmentTransaction ft = getSupportFragmentManager().beginTransaction(); 
    ft.replace(R.id.simple_fragment, newFragment); 
    ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN); 
    ft.addToBackStack(null); 
    ft.commit(); 
} 



public static class MyWebviewFragment extends WebViewFragment { 
    int mNum; 
    private WebView webview = null; 
    private ProgressDialog mSpinner = null; 
    private static final int DIALOG_PROGRESS = 1; 
    private Handler mProgressHandler; 
    boolean bFinishFlag = true; 

    @Override 
    public void onActivityCreated(Bundle savedInstanceState) 
    { 
     // TODO Auto-generated method stub 
     mProgressHandler = new Handler() { 
      @Override 
      public void handleMessage(Message msg) { 
       super.handleMessage(msg); 
       if (bFinishFlag == true) 
        mSpinner.dismiss(); 
       else 
        mProgressHandler.sendEmptyMessageDelayed(0, 100); 
      } 
     }; 

     super.onActivityCreated(savedInstanceState); 
    } 

    /** 
    * Create a new instance of CountingFragment, providing "num" 
    * as an argument. 
    */ 
    static MyWebviewFragment newInstance(int num) { 
     MyWebviewFragment f = new MyWebviewFragment(); 

     // Supply num input as an argument. 
     Bundle args = new Bundle(); 
     args.putInt("num", num); 
     f.setArguments(args); 

     return f; 
    } 

問題行是：

ft.add(R.id.simple_fragment, newFragment).commit(); 

.... 

ft.replace(R.id.simple_fragment, newFragment); 

我想不通爲什麼。 MyWebviewFragment擴展了擴展Fragment的WebViewFragment。 FragmentTransaction方法應該將MyWebviewFragment看作是一個簡單的Fragment。就像我之前說的，這可能與我的進口有關嗎？

謝謝！

Answer 1

MyWebviewFragment擴展了擴展Fragment的WebViewFragment。

您不能混用API 11級本機片段（android.app.Fragment）和Android支持包片段（android.support.v4.app.Fragment）。您無法創建android.webkit.WebViewFragment並將其與android.support.v4.app.FragmentActivity一起使用，因爲android.webkit.WebViewFragment擴展了android.app.Fragment而不是android.support.v4.app.Fragment。

通過創建API級別11+應用程序或不使用WebViewFragment（或將其從源代碼複製並重構爲您的項目），不要使用ActionBarSherlock和Android支持包。