java - 日历 String.valueOf()

Question

我目前正在尝试制作一个日历应用程序，但我的代码出了问题，我无法使用它。目前我制作了一个calendarView并设置了一个onSelectedDateChangeListner并且我分配了带有年、月和日的字符串。我有意将此值传递给另一个类，但即使我单击另一个日期，它仍然保留这个日期(2015.04.20)。对不起我的英语，这不是我的母语。相关代码如下:

MainActivity.java:

    mCalendarView.setOnDateChangeListener(new                   CalendarView.OnDateChangeListener() {
        @Override
        public void onSelectedDayChange(CalendarView view, int year, int   month, int dayOfMonth) {
            Calendar c = Calendar.getInstance();
            String calYear = String.valueOf(c.get(Calendar.YEAR));
            String calMonth = String.valueOf(c.get(Calendar.MONTH)+1);
            String calDay = String.valueOf(c.get(Calendar.DAY_OF_MONTH));

            Intent newEvent = new Intent(MainActivity.this, CalendarEvent.class);

            newEvent.putExtra("YEAR", calYear);
            newEvent.putExtra("MONTH", calMonth);
            newEvent.putExtra("DAY", calDay);

            startActivity(newEvent);
        }
    });

日历事件.java

Bundle extras = getIntent().getExtras();
    if(extras != null){
        mYear = extras.getString("YEAR");
        mMonth = extras.getString("MONTH");
        mDay = extras.getString("DAY");
    }

    TextView hello = (TextView)findViewById(R.id.helloworld);
    hello.setText(mYear + "/" + mMonth + "/" + mDay);

Answer 1

您正在传递日历 c 的值，而不是更改日期的值。您可以通过调用“c.set()”来设置您正在使用的日历实例

mCalendarView.setOnDateChangeListener(new                   CalendarView.OnDateChangeListener() {
    @Override
    public void onSelectedDayChange(CalendarView view, int year, int   month, int dayOfMonth) {
        Calendar c = Calendar.getInstance();
        c.set(year, month, dayOfMonth);
        String calYear = String.valueOf(c.get(Calendar.YEAR));
        String calMonth = String.valueOf(c.get(Calendar.MONTH)+1);
        String calDay = String.valueOf(c.get(Calendar.DAY_OF_MONTH));

        Intent newEvent = new Intent(MainActivity.this, CalendarEvent.class);

        newEvent.putExtra("YEAR", calYear);
        newEvent.putExtra("MONTH", calMonth);
        newEvent.putExtra("DAY", calDay);

        startActivity(newEvent);
    }
});

不过，我认为您想做的就是:

mCalendarView.setOnDateChangeListener(new                   CalendarView.OnDateChangeListener() {
    @Override
    public void onSelectedDayChange(CalendarView view, int year, int   month, int dayOfMonth) {
        Intent newEvent = new Intent(MainActivity.this, CalendarEvent.class);
        newEvent.putExtra("YEAR", String.valueOf(year));
        newEvent.putExtra("MONTH", String.valueOf(month));
        newEvent.putExtra("DAY", String.valueOf(dayOfMonth));
        startActivity(newEvent);
    }
});