CancellableUniqueTask.kt
/*
* Copyright 2020 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 android.os.Handler
import java.time.Duration
/** Task posting helper which allows only one pending task at a time. */
internal class CancellableUniqueTask(private val handler: Handler) {
private var pendingTask: Runnable? = null
fun cancel() {
pendingTask?.let { handler.removeCallbacks(it) }
pendingTask = null
}
fun isPending() = (pendingTask != null)
fun postDelayedUnique(delay: Duration, task: () -> Unit) {
cancel()
val runnable = Runnable {
task()
pendingTask = null
}
handler.postDelayed(runnable, delay.toMillis())
pendingTask = runnable
}
}