FragmentViewLifecycleOwner.java

/*
 * Copyright 2018 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 androidx.fragment.app;

import android.os.Bundle;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.lifecycle.Lifecycle;
import androidx.lifecycle.LifecycleRegistry;
import androidx.savedstate.SavedStateRegistry;
import androidx.savedstate.SavedStateRegistryController;
import androidx.savedstate.SavedStateRegistryOwner;

class FragmentViewLifecycleOwner implements SavedStateRegistryOwner {
    private LifecycleRegistry mLifecycleRegistry = null;
    private SavedStateRegistryController mSavedStateRegistryController = null;

    /**
     * Initializes the underlying Lifecycle if it hasn't already been created.
     */
    void initialize() {
        if (mLifecycleRegistry == null) {
            mLifecycleRegistry = new LifecycleRegistry(this);
            mSavedStateRegistryController = SavedStateRegistryController.create(this);
        }
    }

    /**
     * @return True if the Lifecycle has been initialized.
     */
    boolean isInitialized() {
        return mLifecycleRegistry != null;
    }

    @NonNull
    @Override
    public Lifecycle getLifecycle() {
        initialize();
        return mLifecycleRegistry;
    }

    void setCurrentState(@NonNull Lifecycle.State state) {
        mLifecycleRegistry.setCurrentState(state);
    }

    void handleLifecycleEvent(@NonNull Lifecycle.Event event) {
        mLifecycleRegistry.handleLifecycleEvent(event);
    }

    @NonNull
    @Override
    public SavedStateRegistry getSavedStateRegistry() {
        return mSavedStateRegistryController.getSavedStateRegistry();
    }

    void performRestore(@Nullable Bundle savedState) {
        mSavedStateRegistryController.performRestore(savedState);
    }

    void performSave(@NonNull Bundle outBundle) {
        mSavedStateRegistryController.performSave(outBundle);
    }
}