Question

我试图在屏幕旋转后重新创建视图，她加入了＃34; TestFragment＆＃34;一个活动，屏幕旋转onConfigurationChange（）被调用，这里我做setcontextview（），以便重新创建视图并尝试替换现有的＆＃34; TestFragment＆＃34;同一个实例。但是没有添加片段，我可以在此代码中知道任何错误。

public class TestFragmentActivity extends AppCompatActivity {

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Log.d("Test", "onCreate");
        setContentView(R.layout.activity_test);
        createFragment();
    }

    private void createFragment(){
        Fragment fragment = getSupportFragmentManager().findFragmentByTag("TestFragment");
        if (fragment == null) {
            Log.d("Test", "not found");
            fragment = new TestFragment();

        }else {
            Log.d("Test", "found");
        }
        FragmentTransaction fragmentTransaction;
        fragmentTransaction = getSupportFragmentManager().beginTransaction();
        fragmentTransaction.replace(R.id.frame1, fragment, "TestFragment");
        fragmentTransaction.addToBackStack(null);
        fragmentTransaction.commitAllowingStateLoss();
        getSupportFragmentManager().executePendingTransactions();
    }


    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        Log.d("Test", "onConfigurationChanged");
        setContentView(R.layout.activity_test);
        createFragment();
    }
}

    public class TestFragment extends Fragment {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setRetainInstance(true);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View root = inflater.inflate(R.layout.test_fragment, null, false);
        return root;
    }

    @Override
    public void onDestroy() {
        Log.d("Test", "onDestroy TestFragment");
        super.onDestroy();
    }
}

Answer 1

将此添加到您的清单

<activity
        android:name=".TestFragmentActivity"
        android:configChanges="orientation">   
</activity>

Answer 2

如果在Manifest文件中定义android：configChanges =“orientation”，则无需调用onConfigurationChanged（）方法，因为Activity将自动管理方向更改时的当前状态和内容。

配置更改后未添加片段

2 个答案: