com/android/systemui/shared/system/SystemGestureExclusionListenerCompat.java

/**
 * Copyright (C) 2019 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.android.systemui.shared.system;

import android.graphics.Region;
import android.os.RemoteException;
import android.util.Log;
import android.view.ISystemGestureExclusionListener;
import android.view.WindowManagerGlobal;

/**
 * Utility class to listen for exclusion rect changes.
 */
public abstract class SystemGestureExclusionListenerCompat {

    private static final String TAG = "SGEListenerCompat";

    private final int mDisplayId;

    private ISystemGestureExclusionListener mGestureExclusionListener =
            new ISystemGestureExclusionListener.Stub() {
                @Override
                public void onSystemGestureExclusionChanged(int displayId,
                        Region systemGestureExclusion, Region unrestrictedOrNull) {
                    if (displayId == mDisplayId) {
                        Region unrestricted = (unrestrictedOrNull == null)
                                ? systemGestureExclusion : unrestrictedOrNull;
                        onExclusionChanged(systemGestureExclusion, unrestricted);
                    }
                }
            };
    private boolean mRegistered;

    public SystemGestureExclusionListenerCompat(int displayId) {
        mDisplayId = displayId;
    }

    /**
     * Called when the exclusion region has changed.
     *
     * TODO: remove, once all subclasses have migrated to
     *       {@link #onExclusionChanged(Region, Region)}.
     */
    public abstract void onExclusionChanged(Region systemGestureExclusion);

    /**
     * Called when the exclusion region has changed.
     *
     * @param systemGestureExclusion the system gesture exclusion to be applied
     * @param systemGestureExclusionUnrestricted what would be the system gesture exclusion, if
     *           there were no restrictions being applied. For logging purposes only.
     *
     */
    public void onExclusionChanged(Region systemGestureExclusion,
            Region systemGestureExclusionUnrestricted) {
        // TODO: make abstract, once all subclasses have migrated away from
        //       onExclusionChanged(Region)
        onExclusionChanged(systemGestureExclusion);
    }

    /**
     * Registers the listener for getting exclusion rect changes.
     */
    public void register() {
        if (!mRegistered) {
            try {
                WindowManagerGlobal.getWindowManagerService()
                        .registerSystemGestureExclusionListener(
                                mGestureExclusionListener, mDisplayId);
                mRegistered = true;
            } catch (RemoteException e) {
                Log.e(TAG, "Failed to register window manager callbacks", e);
            }
        }
    }

    /**
     * Unregisters the receiver if previously registered
     */
    public void unregister() {
        if (mRegistered) {
            try {
                WindowManagerGlobal.getWindowManagerService()
                        .unregisterSystemGestureExclusionListener(
                                mGestureExclusionListener, mDisplayId);
                mRegistered = false;
            } catch (RemoteException e) {
                Log.e(TAG, "Failed to unregister window manager callbacks", e);
            }
        }
    }
}