CanvasComplicationFactory.java
/*
* Copyright 2021 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.wear.watchface;
import androidx.annotation.NonNull;
import androidx.annotation.WorkerThread;
/**
* Factory for creating a CanvasComplication. This decouples construction of Complications and
* their CanvasComplication renderers.
*/
// TODO(b/188035300): Put links into the comments.
public interface CanvasComplicationFactory {
/**
* Creates a CanvasComplication. This will be called on a background thread, however all
* CanvasComplication rendering will be done on the UI thread and there's a memory barrier
* between construction and usage so no special threading primitives are required. If the
* CanvasComplication needs to share state with the Renderer then it should override
* onRendererCreated.
*
* @param watchState The current WatchState
* @param invalidateCallback The CanvasComplication.InvalidateCallback the constructed
* CanvasComplication can use to request redrawing. This is typically used in
* conjunction with asynchronous loading of Drawables to update the watch face once the
* drawable has loaded.
* @return The constructed CanvasComplication.
*/
@NonNull
@WorkerThread
@SuppressWarnings("ExecutorRegistration") // This is UI thread only.
CanvasComplication create(
@NonNull WatchState watchState,
@NonNull CanvasComplication.InvalidateCallback invalidateCallback);
}