java - 在MainActivity中从SecondActivity中接收一个字符串值，然后倒计时

Question

在我的程序中，您在 secondActivity 中设置了倒数计时器的字符串值。然后将该值发送到 MainActivities textView，然后该 TextView 应该在获取该值后立即开始倒计时。现在我已经做到了，所以你可以设置值，并且正确获取值，但我不知道如何做的是在收到这个值时开始倒计时。我已经做了一个CounterClass。这是我的 MainActivity 代码...

Bundle extras = getIntent().getExtras();

    String intentString;
    if(extras != null) {
        intentString = extras.getString("TimeValue");
        timer = new CounterClass(60000, 1000);
        timer.start();
        timeSent();

    } else {
        intentString = "Default String";
    }
    textTime= (TextView) findViewById(R.id.timeText);
    textTime.setText(intentString);

Answer 1

您需要启动计时器。总是read the docs .

timer = new CounterClass(millisInFuture, countdownInterval);
timer.start();

编辑

millisInFuture --- The number of millis in the future from the call to start() until the countdown is done and onFinish() is called.

countDownInterval --- The interval along the way to receive onTick(long) callbacks.

编辑 18-12-2015

将您的 intentString 转换为 millisInFuture 并将其发送到 CounterClass。然后在 onTick() 方法中将其格式化回 HH:MM。

String time = "16:54";
String split[] = time.split(":");
long futureInMillis = Integer.parseInt(split[0]) * 60 * 60 * 1000 + Integer.parseInt(split[1]) * 60 * 1000;