java - 使用 setRequestedOrientation() 时出现黑屏

Question

我有一个 FragmentActivity，里面有一些 fragment 。当我从手机处于纵向位置的 fragment ( fragment A)转到我在代码 setOrientation() 中设置为横向的下一个 fragment ( fragment B)时，我按住时出现黑屏在我将手机转到横向之前，纵向手机和布局不会显示在第二个 fragment 上。我的印象是，无论您如何握住手机，当您执行 setRequestedOrientation() 时，它都应该强制显示您提供的布局

视觉:

-----------         -----------         
|         |         |         |                         ---------------
|         |         |         |                         |             |
| Frag A  |   ->    | Frag B  |   -> Until I turn  ->   |   Frag B    | 
|         |(then to)| (black) |     it to Landscape     | (not black  | 
|         |         |         |                         |   anymore)  |
|         |         |         |                         ---------------
-----------         -----------

代码:

保持方向变化的MainActivity:

    // Set Orientation of the Activity.
public void setOrientation(int sensor) {
    if (sensor == 1) {
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_FULL_SENSOR);
    } else if (sensor == 2) {
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_PORTRAIT);
    } else if (sensor == 3) {
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_LANDSCAPE);
    } else if (sensor == 4) {
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
    } else if (sensor == 5) {
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
    }
}

fragment A:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    // Set the orientation to be in portrait and landscape.
    ((MainActivity) getActivity()).setOrientation(1);
    ...
}

fragment B:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    // Set the orientation to be in landscape.
    ((MainActivity) getActivity()).setOrientation(5);
    ...
}

Answer 1

您必须在 onActivityCreated 中调用 getActivity()!