如果您正在使用Xamarin c#，其中一些解决方案将无法工作。这是我发现的一个有效的解决方案。

[Activity(MainLauncher = true, Icon = "@drawable/icon", ScreenOrientation = ScreenOrientation.Portrait)]

上面的类工作得很好，类似于其他解决方案。此外，它不是全局适用的，需要放在每个活动头中。

您必须设置每个活动的方向。

<activity
    android:name="com.example.SplashScreen2"
    android:label="@string/app_name"
    android:screenOrientation="portrait"
    android:theme="@android:style/Theme.Black.NoTitleBar" >
</activity>
<activity
    android:name="com.example.Registration"
    android:label="@string/app_name"
    android:screenOrientation="portrait"
    android:theme="@android:style/Theme.Black.NoTitleBar" >
</activity>
<activity
    android:name="com.example.Verification"
    android:label="@string/app_name"
    android:screenOrientation="portrait"
    android:theme="@android:style/Theme.Black.NoTitleBar" >
</activity>
<activity
    android:name="com.example.WelcomeAlmostDone"
    android:label="@string/app_name"
    android:screenOrientation="portrait"
    android:theme="@android:style/Theme.Black.NoTitleBar" >
</activity>
<activity
    android:name="com.example.PasswordRegistration"
    android:label="@string/app_name"
    android:screenOrientation="portrait"
    android:theme="@android:style/Theme.Black.NoTitleBar" >
</activity>

这对我很管用。尝试在AndroidManifest文件中添加以下代码:

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:screenOrientation="portrait"
    android:theme="@style/AppTheme">
    ....
    ....
</application>

Use:

android:configChanges="keyboardHidden|orientation"
android:screenOrientation="portrait" 

如何在一些视图中改变方向

不是锁定整个活动的方向，你可以使用这个类从你的任何视图中动态地锁定方向:

让你的视图成为景观

OrientationUtils.lockOrientationLandscape(mActivity);

将视图设置为竖屏

OrientationUtils.lockOrientationPortrait(mActivity);

解锁取向

OrientationUtils.unlockOrientation(mActivity);

方向Util类

import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.content.res.Configuration;
import android.os.Build;
import android.view.Surface;
import android.view.WindowManager;

/*  * This class is used to lock orientation of android app in nay android devices
 */

public class OrientationUtils {
    private OrientationUtils() {
    }

    /** Locks the device window in landscape mode. */
    public static void lockOrientationLandscape(Activity activity) {
        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_LANDSCAPE);
    }

    /** Locks the device window in portrait mode. */
    public static void lockOrientationPortrait(Activity activity) {
        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
    }

    /** Locks the device window in actual screen mode. */
    public static void lockOrientation(Activity activity) {
        final int orientation = activity.getResources().getConfiguration().orientation;
        final int rotation = ((WindowManager) activity.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay()
                .getRotation();

        // Copied from Android docs, since we don't have these values in Froyo
        // 2.2
        int SCREEN_ORIENTATION_REVERSE_LANDSCAPE = 8;
        int SCREEN_ORIENTATION_REVERSE_PORTRAIT = 9;

        // Build.VERSION.SDK_INT <= Build.VERSION_CODES.FROYO
        if (!(Build.VERSION.SDK_INT <= Build.VERSION_CODES.FROYO)) {
            SCREEN_ORIENTATION_REVERSE_LANDSCAPE = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
            SCREEN_ORIENTATION_REVERSE_PORTRAIT = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
        }

        if (rotation == Surface.ROTATION_0 || rotation == Surface.ROTATION_90) {
            if (orientation == Configuration.ORIENTATION_PORTRAIT) {
                activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
            } else if (orientation == Configuration.ORIENTATION_LANDSCAPE) {
                activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
            }
        } else if (rotation == Surface.ROTATION_180 || rotation == Surface.ROTATION_270) {
            if (orientation == Configuration.ORIENTATION_PORTRAIT) {
                activity.setRequestedOrientation(SCREEN_ORIENTATION_REVERSE_PORTRAIT);
            } else if (orientation == Configuration.ORIENTATION_LANDSCAPE) {
                activity.setRequestedOrientation(SCREEN_ORIENTATION_REVERSE_LANDSCAPE);
            }
        }
    }

    /** Unlocks the device window in user defined screen mode. */
    public static void unlockOrientation(Activity activity) {
        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_USER);
    }

}

如果您正在使用Xamarin c#，其中一些解决方案将无法工作。这是我发现的一个有效的解决方案。

[Activity(MainLauncher = true, Icon = "@drawable/icon", ScreenOrientation = ScreenOrientation.Portrait)]

上面的类工作得很好，类似于其他解决方案。此外，它不是全局适用的，需要放在每个活动头中。