Upgraded to AppCompat v22.1.0 and now onKeyDown and onKeyUp are not triggered when menu key is pressed

问题

I've just upgraded my app to use the newly released v22.1.0 AppCompat and now onKeyDown and onKeyUp are not triggered when menu key is pressed. The other keys correctly trigger onKeyDown and onKeyUp, but when i press the menu key nothing happens. If I downgrade to v22.0.0 everything returns to work properly.

How do I fix it?

回答1:

Update 23 August

This has been fixed again in the v23.0.0 of appcompat-v7 support library. Update to the last version to see this fixed.

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Update 19 July

Unfortunately AppCompat v22.2.1 broke the onKeyDown and onKeyUp events again. I just updated AppCompatActivityMenuKeyInterceptor to support v22.1.x and also v22.2.1

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Update 29 May

This has been fixed in the v22.2.0 of appcompat-v7 support library. Update to the last version to see this fixed.

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Unfortunately AppCompat v22.1.0 intercepts the onKeyDown and onKeyUp events and does not propagate them when the menu key is pressed. The only possible solution involves using Reflection to intercept the onKeyDown and onKeyUp events before the AppCompat does.

Add this class to your project:

public class AppCompatActivityMenuKeyInterceptor {

    private static final String FIELD_NAME_DELEGATE = "mDelegate";
    private static final String FIELD_NAME_WINDOW = "mWindow";

    public static void intercept(AppCompatActivity appCompatActivity) {
        new AppCompatActivityMenuKeyInterceptor(appCompatActivity);
    }

    private AppCompatActivityMenuKeyInterceptor(AppCompatActivity activity) {
        try {
            Field mDelegateField = AppCompatActivity.class.getDeclaredField(FIELD_NAME_DELEGATE);
            mDelegateField.setAccessible(true);
            Object mDelegate = mDelegateField.get(activity);

            Class mDelegateClass = mDelegate.getClass().getSuperclass();
            Field mWindowField = null;

            while (mDelegateClass != null) {
                try {
                    mWindowField = mDelegateClass.getDeclaredField(FIELD_NAME_WINDOW);
                    break;
                } catch (NoSuchFieldException ignored) {
                }

                mDelegateClass = mDelegateClass.getSuperclass();
            }

            if (mWindowField == null)
                throw new NoSuchFieldException(FIELD_NAME_WINDOW);

            mWindowField.setAccessible(true);
            Window mWindow = (Window) mWindowField.get(mDelegate);

            Window.Callback mOriginalWindowCallback = mWindow.getCallback();
            mWindow.setCallback(new AppCompatWindowCallbackCustom(mOriginalWindowCallback, activity));
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }

    private class AppCompatWindowCallbackCustom extends WindowCallbackWrapper {

        private WeakReference<AppCompatActivity> mActivityWeak;

        public AppCompatWindowCallbackCustom(Window.Callback wrapped, AppCompatActivity appCompatActivity) {
            super(wrapped);

            mActivityWeak = new WeakReference<AppCompatActivity>(appCompatActivity);
        }

        @Override
        public boolean dispatchKeyEvent(KeyEvent event) {
            final int keyCode = event.getKeyCode();

            AppCompatActivity appCompatActivity = mActivityWeak.get();

            if (appCompatActivity != null && keyCode == KeyEvent.KEYCODE_MENU) {
                if (appCompatActivity.dispatchKeyEvent(event))
                    return true;
            }

            return super.dispatchKeyEvent(event);
        }
    }
}

Call AppCompatActivityMenuKeyInterceptor.intercept(this) in the onCreate of your activity:

public class MainActivity extends AppCompatActivity {

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

        //Initialize the interceptor
        AppCompatActivityMenuKeyInterceptor.intercept(this);
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // Now onKeyDown is called also for KEYCODE_MENU
        if (keyCode == KeyEvent.KEYCODE_MENU) {
            //do your stuff

            //return false if you want to propagate the
            //KeyEvent to AppCompat, return true otherwise
            return false;
        }

        return super.onKeyDown(keyCode, event);
    }

    @Override
    public boolean onKeyUp(int keyCode, KeyEvent event) {
        // Now onKeyUp is called also for KEYCODE_MENU
        if (keyCode == KeyEvent.KEYCODE_MENU) {
            //do your stuff

            //return false if you want to propagate the
            //KeyEvent to AppCompat, return true otherwise
            return false;
        }

        return super.onKeyUp(keyCode, event);
    }
}

If you use ProGuard or DexGuard add these rules to your configuration:

-keepclassmembers class android.support.v7.app.AppCompatActivity {
    private android.support.v7.app.AppCompatDelegate mDelegate;
}

-keepclassmembers class android.support.v7.app.AppCompatDelegateImplBase {
    final android.view.Window mWindow;
}

Now your activity can receive onKeyDown and onKeyUp event also for the menu key.

回答2:

Instead of onKeyUp() or onKeyDown(), one can simply use dispatchKeyEvent(). Look at the following code from android-developers.blogspot.com.

@Override
public boolean dispatchKeyEvent(KeyEvent event) {
    if (event.getKeyCode() == KeyEvent.KEYCODE_BACK) {
        if (event.getAction() == KeyEvent.ACTION_DOWN
                && event.getRepeatCount() == 0) {

            // Tell the framework to start tracking this event.
            getKeyDispatcherState().startTracking(event, this);
            return true;

        } else if (event.getAction() == KeyEvent.ACTION_UP) {
            getKeyDispatcherState().handleUpEvent(event);
            if (event.isTracking() && !event.isCanceled()) {
                // DO BACK ACTION HERE
                return true;
            }
        }
        return super.dispatchKeyEvent(event);
    } else {
        return super.dispatchKeyEvent(event);
    }
}

来源：https://stackoverflow.com/questions/29852303/upgraded-to-appcompat-v22-1-0-and-now-onkeydown-and-onkeyup-are-not-triggered-wh