实现5秒倒计时

/**
 * 定义 handler 实现倒计时功能
 * */
private val mHandler: TimeHandler = TimeHandler(this)

/**
 * 倒计时5秒关闭页面
 * */
private class TimeHandler(activity: CompanyVerifiedSuccessActivity) : Handler() {
    val mWeakReference: WeakReference = WeakReference(activity)
    override fun handleMessage(msg: Message) {
        super.handleMessage(msg)
        mWeakReference.get()?.run {
            if (mTime == 0) {
                finish()
                removeCallbacksAndMessages(null)
            } else {
                val info = getString(R.string.company_verified_success_jump_tips) + mTime--
                mBinding.tvTimeTips.text = info
                sendEmptyMessageDelayed(0, 1000)
            }
        }
    }
}

onCreate中   
mHandler.sendEmptyMessageDelayed(0, 1000)

另一种写法：

job = GlobalScope.launch {
    repeat(5) { i ->
        delay(1000L)
        runOnUiThread {
            tvJumpTime.text = 正在跳转+ 4-i
            if (i == 4) {
               finish()
            }
        }
    }
}

new Thread(() -> {
    try {
        for (int i = 0; i <= 3; i++) {
            if (i == 3) {
                startActivity(new Intent(context, MainActivity.class));
                finish();
            } else {
                String temp = getString(R.string.splash_skip, String.valueOf(3 - i));
                runOnUiThread(() -> tvSkip.setText(temp));
            }
            Thread.sleep(1000);
        }
    } catch (Exception ignored) {
    }
}).start();