我试着加载一个新的片段，当方法被调用。此方法创建一个新的片断和替代另一个片段：

Im trying to load an new fragment when a method is called. This method creates a new fragment and "replaces" the other fragment:

private void showTestFragment(Fragment oldFragment, boolean addBackStack, BaseAdapter adapter, int position) {
    Cursor cursor = (Cursor)adapter.getItem(position);
    if(cursor != null){

        int idx = cursor.getColumnIndexOrThrow(Episode._ID);
        long rowId = cursor.getLong(idx);

        FragmentManager fragmentManager = getFragmentManager();
        FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();

        if(oldFragment != null){
            Log.i(TAG, "Removing the old fragment");
            fragmentTransaction.remove(oldFragment);
        }

        TestFragment testFragment =  new TestFragment();
        testFragment.setId(rowId);

        fragmentTransaction.add(android.R.id.content, testFragment);

        if(addBackStack){
            Log.i(TAG, "Added to the backstack");
            fragmentTransaction.addToBackStack(TAG);
        }

        fragmentTransaction.commit();
        Fragment f = getFragmentManager()
                .findFragmentById(R.id.index);
        Log.i(TAG, "after commit, frag is "+ f);
    }
}

这工作得很好，直到我回去。最后一个片段，当我回去应该被删除。我要去实现的活动方法之前，

This works fine, until i go back. The last fragment, should be removed when i go back. Before i'm going to implement methods on the activities

public void onBackPressed(){}

要删除最后一个片段，我想知道如果我正确处理片段的变化。它看起来像我想的东西在这里..

to remove the last fragment, i want to know if i handle the fragment change correctly. It looks like i'm missing something here..

推荐答案

如果你真的想取代而不是做一个删除（）和一个附加（）。

If you really want to replace the fragment then use replace() methode instead of doing a remove() and an add().

    FragmentManager fragmentManager = getFragmentManager();
    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
    fragmentTransaction.replace(..............);
    fragmentTransaction.addToBackStack(null);
    fragmentTransaction.commit(); 

不要忘记做addToBackStack（空），这样您previous状态将被添加到backstack让你的后退按钮返回。

Don't forget to do the addToBackStack(null) so your previous state will be added to the backstack allowing you to go back with the back button.

另请参见http://developer.android.com/reference/android/app/FragmentTransaction.html#replace(int, android.app.Fragment，java.lang.String中）。

See also http://developer.android.com/reference/android/app/FragmentTransaction.html#replace(int, android.app.Fragment, java.lang.String) .

另外一个很好的来源是http://developer.android.com/guide/components/fragments.html （搜索替换（）函数）。

Another good source is http://developer.android.com/guide/components/fragments.html (search for replace() function).