android - 从 FragmentActivity 转换为 ActionBarActivity 导致在方向更改期间崩溃

Question

我正在尝试将我的 v4 FragmentActivity 转换为更新的 ActionBarActivity，以便利用更好的向后兼容性。但是，从 FragmentActivity 切换到 ActionBarActivity 时，我遇到了方向更改的问题。这是一个简单的例子:

当我扩展 FragmentActivity 时，以下 Activity 可以正常工作:

public class MainActivityBlank extends FragmentActivity implements NavigationDrawerFragment.NavigationDrawerCallbacks {

        private int mCurrentPagerItem;
        private static final String NEWS_FRAG_TAG = "NEWSFRAG";

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            setContentView(R.layout.activity_main_test);

        }


        @Override
        public void onNavigationDrawerItemSelected(int position) {

            FragmentManager fragmentManager = getSupportFragmentManager();
            mCurrentPagerItem = position;
            //onSectionAttached(position);
            switch (position) {
                case 0: // News

                    Fragment newsFragment;
                    if (fragmentManager.findFragmentByTag(NEWS_FRAG_TAG) == null) {
                        newsFragment = new NewsListFragment();
                    } else {
                        newsFragment = fragmentManager.findFragmentByTag(NEWS_FRAG_TAG);
                    }
                    fragmentManager.beginTransaction()
                            .replace(R.id.container, newsFragment, NEWS_FRAG_TAG)
                            .commit();

                    break;
            }

        }
      }

我现在尝试扩展 ActionBarAcitivty。没有改变任何其他东西。

    public class MainActivityBlank extends ActionBarActivity implements NavigationDrawerFragment.NavigationDrawerCallbacks {

        private int mCurrentPagerItem;
        private static final String NEWS_FRAG_TAG = "NEWSFRAG";

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            setContentView(R.layout.activity_main_test);

        }


        @Override
        public void onNavigationDrawerItemSelected(int position) {

            FragmentManager fragmentManager = getSupportFragmentManager();
            mCurrentPagerItem = position;
            //onSectionAttached(position);
            switch (position) {
                case 0: // News

                    Fragment newsFragment;
                    if (fragmentManager.findFragmentByTag(NEWS_FRAG_TAG) == null) {
                        newsFragment = new NewsListFragment();
                    } else {
                        newsFragment = fragmentManager.findFragmentByTag(NEWS_FRAG_TAG);
                    }
                    fragmentManager.beginTransaction()
                            .replace(R.id.container, newsFragment, NEWS_FRAG_TAG)
                            .commit();

                    break;
            }

        }
    }

这会导致屏幕旋转时出现以下错误:

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tykin.app/com.tykin.app.common.MainActivityBlank}: android.util.AndroidRuntimeException: requestFeature() must be called before adding content
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
        at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3738)
        at android.app.ActivityThread.access$900(ActivityThread.java:135)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1202)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:136)
        at android.app.ActivityThread.main(ActivityThread.java:5017)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:515)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
        at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:126)
        at dalvik.system.NativeStart.main(Native Method)
 Caused by: android.util.AndroidRuntimeException: requestFeature() must be called before adding content
        at com.android.internal.policy.impl.PhoneWindow.requestFeature(PhoneWindow.java:249)
        at android.app.Activity.requestWindowFeature(Activity.java:3298)
        at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:63)
        at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:98)
        at com.tykin.app.common.MainActivityBlank.onCreate(MainActivityBlank.java:20)
        at android.app.Activity.performCreate(Activity.java:5231)

我的代码中没有调用 requestFeature() 的地方

任何帮助将不胜感激

Answer 1

原来问题出在我的 NewsListFragment 中。具体来说，它来自 getActionBar 调用，我没有更改它以支持 v7 支持库。对于我的每个 fragment ，我首先必须更改我的库导入，然后通过更改清理我的代码

ActionBar actionBar = getActivity().getActionBar();

到

ActionBar actionBar = ((ActionBarActivity)getActivity()).getSupportActionBar();