天文台在改变方向时重新启动

Question

我在你改变方向时重置了计时表的值，写的是真的，但没有帮助，求帮助，出了什么问题

@Override
protected void onSaveInstanceState(Bundle outState) {
timer = SystemClock.elapsedRealtime() - chronometer.getBase();
outState.putLong("timerValue", timer);
super.onSaveInstanceState(outState);
}

@Override
protected void onCreate(final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.details_layout);

chronometer = (Chronometer) findViewById(R.id.chronometer);
chronometer.setBase(SystemClock.elapsedRealtime());
if (savedInstanceState != null) {
    chronometer.setOnChronometerTickListener(new Chronometer.OnChronometerTickListener() {
        public void onChronometerTick(Chronometer chronometer) {
            timer = savedInstanceState.getLong("timerValue");
            chronometer.setText(DateFormat.format("mm:ss", timer));
        }
    });
    chronometer.start();
} else {
    chronometer.setOnChronometerTickListener(new Chronometer.OnChronometerTickListener() {
        public void onChronometerTick(Chronometer chronometer) {
            timer = SystemClock.elapsedRealtime() - chronometer.getBase();
            chronometer.setText(DateFormat.format("mm:ss", timer));
        }
    });
    chronometer.start();
}
}

Answer 1

注意：每次用户旋转屏幕时，您的 Activity 都会被销毁并重新创建。当屏幕改变方向时，系统会销毁并重新创建前台 Activity，因为屏幕配置已更改并且您的 Activity 可能需要加载替代资源（例如布局）。

见： How to contain value of android chronometer with change in orientation