如何检测屏幕旋转？

Question

是否可以检测屏幕旋转？我的意思是 - 仅轮换，这与活动初始化与另一个活动有明显区别？

onXxx 方法似乎对此没有用，我尝试从starting Intent 添加/删除flag（删除似乎没有反映，旋转标志在那里），并尝试添加android:configChanges="orientation" 用于清单中的活动，但是 onConfigurationChanged 方法似乎每隔一秒就会被调用一次......有线。

我想我遗漏了一些东西......但在其他相关线程中没有找到明确的解决方案。

有什么想法吗？

Answer 1

清单：

<activity android:name=".MyActivity" android:configChanges="screenSize|orientation|screenLayout|navigation"/>

活动：

@Override
public void onConfigurationChanged(Configuration newConfig)
{
    Log.d("tag", "config changed");
    super.onConfigurationChanged(newConfig);

    int orientation = newConfig.orientation;
    if (orientation == Configuration.ORIENTATION_PORTRAIT)
        Log.d("tag", "Portrait");
    else if (orientation == Configuration.ORIENTATION_LANDSCAPE)
        Log.d("tag", "Landscape");
    else
        Log.w("tag", "other: " + orientation);

    ....
}

也试试这个链接

How do I detect screen rotation

Answer 2

使用 onConfigurationChanged 方法来检测屏幕旋转不是一个好主意。当用户旋转屏幕时，此活动中的配置更改将无法正常工作。

所以我用这个方案来解决这个问题。

public class SampleActivity extends AppCompatActivity {
    public static final String KEY_LAST_ORIENTATION = "last_orientation";
    private int lastOrientation;

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

        if (savedInstanceState == null) {
            lastOrientation = getResources().getConfiguration().orientation;
        }
    }

    @Override
    protected void onStart() {
        super.onStart();
        checkOrientationChanged();
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        lastOrientation = savedInstanceState.getInt(KEY_LAST_ORIENTATION);
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putInt(KEY_LAST_ORIENTATION, lastOrientation);
    }

    private void checkOrientationChanged() {
        int currentOrientation = getResources().getConfiguration().orientation;
        if (currentOrientation != lastOrientation) {
            onScreenOrientationChanged(currentOrientation);
            lastOrientation = currentOrientation;
        }
    }

    public void onScreenOrientationChanged(int currentOrientation) {
        // Do something here when screen orientation changed
    }
}

但是代码仍然不够好，无法在我的项目中使用它，所以我将此代码应用到我自己的库中 (https://github.com/akexorcist/ScreenOrientationHelper)。

compile 'com.akexorcist:screenorientationhelper:<latest_version>'

您可以像这样创建基本活动类

    public class BaseActivity extends AppCompatActivity implements ScreenOrientationHelper.ScreenOrientationChangeListener {
    private ScreenOrientationHelper helper = new ScreenOrientationHelper(this);

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        helper.onCreate(savedInstanceState);
        helper.setScreenOrientationChangeListener(this);
    }

    @Override
    protected void onStart() {
        super.onStart();
        helper.onStart();
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        helper.onSaveInstanceState(outState);
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        helper.onRestoreInstanceState(savedInstanceState);
    }

    @Override
    public void onScreenOrientationChanged(int orientation) {

    }
}

然后用这个基类扩展activity

public class MainActivity extends BaseActivity {

    ...

    @Override
    public void onScreenOrientationChanged(int orientation) {
        // Do something when screen orientation changed
    }
}

完成！

Answer 3

你为什么不试试这个？

在onCreated中获取手机的方向：

Display display = ((WindowManager)getSystemService(WINDOW_SERVICE)).getDefaultDisplay();
myOrientation = display.getOrientation();

然后，覆盖方法 onConfigurationChanged 并检查方向是否已更改：

@Override
public void onConfigurationChanged(Configuration newConfig) {
    if(newConfig.orientation != myOrientation)
        Log.v(tag, "rotated");
    super.onConfigurationChanged(newConfig);
}

不要忘记将android:configChanges="orientation" 添加到活动的清单中。