Question

我是Android \ Java的新手，我有以下问题：如何检查屏幕方向更改？

当然我发现了很多关于这个主题的文章，但是没有一篇文章适合我，所以我可能做错了。

我不明白的一件事是：我需要实现OrientationEventListener吗？或者是＆＃34; onConfigurationChanged＆＃34;够了？或者我需要两者吗？

例如，我尝试运行使用＆＃34; onConfigurationChanged＆＃34;的下列代码。 - 但是永远不会调用onConfigurationChanged。（我已将android：configChanges =＆＃34; orientation | screenSize | keyboardHidden＆＃34;添加到manifest.xml，我为API构建＆gt; 13）

所以我的问题是：为什么＆＃34; onConfigurationChanged（）＆＃34;从未执行过？我已经在真实设备（三星Galaxy Note）和模拟器上尝试过它。

public class main_activity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_layout);
    }


    @Override
    public void onConfigurationChanged(Configuration newConfig)     <--- this is never called
    {
        super.onConfigurationChanged(newConfig);

        // Checks the orientation of the screen     
        if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
            Toast.makeText(this, "landscape", Toast.LENGTH_SHORT).show();
        } else if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT){
            Toast.makeText(this, "portrait", Toast.LENGTH_SHORT).show();
        }
    }
}

清单：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.test.andro" >

    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >

        <activity
            android:name=".main_activity"
            android:configChanges="orientation|screenSize|keyboardHidden"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
</application>

的build.gradle：

android {
    compileSdkVersion 21
    buildToolsVersion "21.1.2"

    defaultConfig {
        applicationId "com.example.test.andro"
        minSdkVersion 19
        targetSdkVersion 21
        versionCode 1
        versionName "1.0"
    }

Answer 1

试试这个

    orientationListener = new OrientationEventListener(context, SensorManager.SENSOR_DELAY_UI) {
        public void onOrientationChanged(int orientation) {
            if(canShow(orientation)){
                show();
            } else if(canDismiss(orientation)){
                dismiss();
            }
        }
    };

@Override
public void onResume(){
    super.onResume();
    orientationListener.enable();
}

@Override
public void onPause(){
    super.onPause();
    orientationListener.disable();
}

private boolean isLandscape(int orientation){
        return orientation >= (90 - THRESHOLD) && orientation <= (90 + THRESHOLD);
    }

private boolean isPortrait(int orientation){
    return (orientation >= (360 - THRESHOLD) && orientation <= 360) || (orientation >= 0 && orientation <= THRESHOLD);
}

public boolean canShow(int orientation){
    return !visible && isLandscape(orientation);
}

public boolean canDismiss(int orientation){
    return visible && !dismissing && isPortrait(orientation);
}

Answer 2

在您想要检查活动方向的地方使用此代码：

protected void onResume(Bundle savedInstanceState) 
 {
  super.onResume();

  int rotation = getWindowManager().getDefaultDisplay().getRotation();
        // DisplayMetrics dm = new DisplayMetrics();
        // getWindowManager().getDefaultDisplay().getMetrics(dm);
        if(rotation == 0)
            text="Portrait";
        else if(rotation == 1)
            text="Rotated left side";
        else
            text="Rotated right side";

  Toast toast = Toast.makeText(getApplicationContext(), text,Toast.LENGTH_SHORT);
        toast.setGravity(Gravity.CENTER | Gravity.CENTER, 10, 0);
        toast.show();
}

Android方向更改（onConfigurationChanged / OrientationEventListener）

2 个答案: