android - 使用 setRequestedConfiguration 后不会调用 onConfigurationChanged

Question

我已经设置了 am Activity 来处理配置更改并且它有效，这意味着当方向更改时调用 onConfigurationChanged()。

该 Activity 有一个按钮可以明确更改方向。单击时，它会调用 setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_PORTRAIT)。

然后不可撤销地设置方向并且不再调用 onConfigurationChanged()。

当用户单击按钮时如何在不丢失 onConfigurationChanged() 回调的情况下更改方向？

Answer 1

我就是这样解决的。我知道这是在重新发明轮子，但它满足了我的要求，但我没有找到使用标准 sdk 工具处理此问题的正确方法。

首先，创建一个监听方向变化的OrientationManager类

public class OrientationManager extends OrientationEventListener{
private static final String TAG = OrientationManager.class.getName();

private int previousAngle;
private int previousOrientation;
private Context context;
private OrientationChangeListener orientationChangeListener;
private static OrientationManager instance;
private OrientationManager(Context context) {
    super(context);
    this.context = context;
}

public static OrientationManager  getInstance(Context context){
    if (instance == null){
        instance = new OrientationManager(context);
    }
    return instance;
}

public int getOrientation(){
    return previousOrientation;
}

public void setOrientation(int orientation){
    this.previousOrientation = orientation;
}


@Override
public void onOrientationChanged(int orientation) {
    if (orientation == -1)
        return;
    if(previousOrientation == 0){
        previousOrientation = context.getResources().getConfiguration().orientation;
        if (orientationChangeListener != null){
            orientationChangeListener.onOrientationChanged(previousOrientation);
        }           
    }
    if (previousOrientation == Configuration.ORIENTATION_LANDSCAPE &&
            ((previousAngle > 10 && orientation <= 10) ||
            (previousAngle < 350 && previousAngle > 270 && orientation >= 350)) ){
        if (orientationChangeListener != null){
            orientationChangeListener.onOrientationChanged(Configuration.ORIENTATION_PORTRAIT);
        }
        previousOrientation = Configuration.ORIENTATION_PORTRAIT;
    }

    if (previousOrientation == Configuration.ORIENTATION_PORTRAIT &&
            ((previousAngle <90 && orientation >= 90 && orientation <270) ||
            (previousAngle > 280 && orientation <= 280 && orientation > 180))   ){
        if (orientationChangeListener != null){
            orientationChangeListener.onOrientationChanged(Configuration.ORIENTATION_LANDSCAPE);
        }
        previousOrientation = Configuration.ORIENTATION_LANDSCAPE;
    }
    previousAngle = orientation;
}

public void setOrientationChangedListener(OrientationChangeListener l){
    this.orientationChangeListener = l;
}

public interface OrientationChangeListener{
    public void onOrientationChanged(int newOrientation);
}
}

然后在您的 Activity 中实现 OrientationChangeListener 并覆盖 onOrientationChanged():

public class MyActivity extends Activity implements OrientationChangeListener{

    private OrientationManager orientationManager;

    @Override
    public void onCreate(Bundle b){
        orientationManager = OrientationManager.getInstance(this);
        orientationManager.setOrientationChangedListener(this);

    }

@Override
public void onOrientationChanged(int newOrientation) {
    orientation = newOrientation;
    if (newOrientation == Configuration.ORIENTATION_LANDSCAPE){
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_LANDSCAPE);
        setLandscapeConfig();
    }else{
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        setPortraitConfig();
    }
}

所以我不再使用 onConfigurationChanged 但在 list 中保留以下行: android:configChanges="方向|屏幕大小"