Android 倒计时一般实现方式：
现在因为有了协程和Flow,我们可以借助Flow这个工具,更加优雅地实现这个需求功能.
api 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.4.2'
api 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.4.1'
// lifecycleScope(可选)
api "androidx.lifecycle:lifecycle-runtime-ktx:2.2.0"fun countDownCoroutines(
total: Int,
scope: CoroutineScope,
onTick: (Int) -> Unit,
onStart: (() -> Unit)? = null,
onFinish: (() -> Unit)? = null,
): Job {
return flow {
for (i in total downTo 0) {
emit(i)
delay(1000)
}
}.flowOn(Dispatchers.Main)
.onStart { onStart?.invoke() }
.onCompletion { onFinish?.invoke() }
.onEach { onTick.invoke(it) }
.launchIn(scope)
}private var mCountdownJob: Job? = null
mBinding.btnStart.setOnClickListener {
mCountdownJob = countDownCoroutines(60, lifecycleScope,
onTick = { second ->
mBinding.text.text = "${second}s后重发"
}, onStart = {
// 倒计时开始
}, onFinish = {
// 倒计时结束，重置状态
mBinding.text.text = "发送验证码"
})
}
mBinding.btnStop.setOnClickListener {
// 取消倒计时
mCountdownJob?.cancel() 其他的完整Demo https://github.com/dahui888/kotlinpractice
补充：
下面是小编收集整理Android 实现倒计时的几种方式
/**
* 开始
*/
public void startTimer() {
if (timer == null) {
timer = new Timer();
}
if (timerTask == null) {
timerTask = new TimerTask() {
@Override
public void run() {
Message message = new Message();
message.what = 2;
handler.sendMessage(message);
}
};
}
if (timer != null && timerTask != null) {
timer.schedule(timerTask, 0, 2000);
}
}
/**
* 暂停定时器
*/
public void stopTimer() {
if (timer != null) {
timer.cancel();
timer = null;
}
if (timerTask != null) {
timerTask.cancel();
timerTask = null;
}
} private void countDown() {
mdDisposable = Flowable.intervalRange(0, Constant.COUNT_DOWN, 0, 1,TimeUnit.SECONDS)
.observeOn(AndroidSchedulers.mainThread())
.doOnNext((aLong) -> LogUtils.e("倒计时--" + aLong))
.doOnComplete(() -> randomSelectSeat())
.subscribe();
}
/**
* 销毁
*/
@Override
protected void onDestroy() {
if (mdDisposable != null) {
mdDisposable.dispose();
}
super.onDestroy();
}//倒计时CountDownTimer
//每过1000毫秒执行一次onTick
//倒计时完成执行onFinish
CountDownTimer timer = new CountDownTimer(5000, 1000){
@Override
public void onTick(long sin) {
Toast.makeText(MainActivity.this, "" + sin/1000, Toast.LENGTH_SHORT).show();
}
@Override
public void onFinish() {
Toast.makeText(MainActivity.this, "倒计时完成", Toast.LENGTH_SHORT).show();
}
};
//开始
timer.start();
//暂停
if (timer != null) {
timer.cancel();
timer = null;
}
