如何使用 kotlin 中的播放、暂停和重置按钮使循环进度倒计时答案

【问题标题】：how to make circular progress count down timer with having Play,Pause and Reset buttton in kotline如何使用 kotlin 中的播放、暂停和重置按钮使循环进度倒计时
【发布时间】：2023-02-24 02:22:57
【问题描述】：

使用共享偏好

如何使用 kotlin 中的播放、暂停和重置按钮使循环进度倒计时

【问题讨论】：

标签： android

【解决方案1】：

类 MainActivity : AppCompatActivity() {

private lateinit var progressBar: ProgressBar
private lateinit var textView: TextView
private lateinit var playButton: Button
private lateinit var pauseButton: Button
private lateinit var resetButton: Button
private lateinit var countDownTimer: CountDownTimer

private var totalTime = 60000L //total countdown time in milliseconds
private var timeLeft = totalTime

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    progressBar = findViewById(R.id.progressBar)
    textView = findViewById(R.id.textView)
    playButton = findViewById(R.id.playButton)
    pauseButton = findViewById(R.id.pauseButton)
    resetButton = findViewById(R.id.resetButton)

    progressBar.max = totalTime.toInt()

    countDownTimer = object : CountDownTimer(totalTime, 1000) {
        override fun onTick(millisUntilFinished: Long) {
            timeLeft = millisUntilFinished
            updateTimer()
        }

        override fun onFinish() {
            timeLeft = 0
            updateTimer()
        }
    }

    playButton.setOnClickListener {
        countDownTimer.start()
    }

    pauseButton.setOnClickListener {
        countDownTimer.cancel()
    }

    resetButton.setOnClickListener {
        countDownTimer.cancel()
        timeLeft = totalTime
        updateTimer()
        progressBar.progress = totalTime.toInt()
    }
}

private fun updateTimer() {
    val minutes = (timeLeft / 1000) / 60
    val seconds = (timeLeft / 1000) % 60
    val timeLeftFormatted = String.format(Locale.getDefault(), "%02d:%02d", minutes, seconds)
    textView.text = timeLeftFormatted
    progressBar.progress = (totalTime - timeLeft).toInt()
}

}

【讨论】：