我有一个秒表应用程序,它只有一个活动。三个按钮启动、停止、重置和一个显示计时器的文本视图。这是我的代码:
public class StopwatchActivity extends AppCompatActivity {
private int mNumberOfSeconds = 0;
private boolean mRunning = false;
private Handler handler = new Handler();
private Runnable runnable;
private TextView timeview;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_stopwatch);
if (savedInstanceState != null){
mNumberOfSeconds = savedInstanceState.getInt("number_of_second");
mRunning = savedInstanceState.getBoolean("is_running");
Log.e("after orient mSecond :" , String.valueOf(mNumberOfSeconds));
Log.e("after orient mRunning :" , String.valueOf(mRunning));
runner();
}
}
public void onClickStart(View view){
handler.removeCallbacks(runnable);
mRunning = true;
runner();
}
public void onClickStop(View view){
mRunning = false;
handler.removeCallbacks(runnable);
}
public void onClickReset(View view){
mRunning = false;
//mNumberOfSeconds = 0;
//timeview.setText("0:00:00");
}
public void runner(){
timeview = (TextView) findViewById(R.id.time_view);
runnable = new Runnable() {
@Override
public void run() {
int hours = mNumberOfSeconds/3600;
int minutes = (mNumberOfSeconds%3600)/60;
int second = mNumberOfSeconds%60;
String time = String.format("%d:%02d:%02d" , hours , minutes , second );
timeview.setText(time);
if (mRunning){
mNumberOfSeconds++;
}
handler.postDelayed(this , 1000);
}
};
handler.post(runnable);
}
@Override
protected void onSaveInstanceState(Bundle outState) {
outState.putInt("number_of_seconds" , mNumberOfSeconds);
outState.putBoolean("is_running" , mRunning);
Log.e("befor rotation second:" , String.valueOf(mNumberOfSeconds));
Log.e("befor rotaion mrunning" , String.valueOf(mRunning));
}
我想将我的一些变量保存在 onSaveInstanceState 中,以便在改变方向后再次使用它们。正如您在代码中看到的,日志消息显示方向更改前后的 mNumberOfSeconds 和 mRunning 的值。并且在方向更改后 mNumberOfSeconds 会给我 0 而不是我保存的值。但是 mRunning 给了我正确的价值。谁能给我任何解决方案?