Question

我按下了一个按钮来打开日期和时间选择器，但必须选中CheckBox才能激活我的按钮。没有复选框，它工作正常，chekbox选中或取消选中，它不会打开日期选择器。你能告诉我为什么吗？

protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_new);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    pick_date = (Button) findViewById(R.id.pick_date);
    tv_result = (TextView) findViewById(R.id.tvdate_result);
    CheckBox fixed_date_flag = (CheckBox) findViewById(R.id.fixed_date);
    final boolean checked = (fixed_date_flag).isChecked();

    if(checked){
    pick_date.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View view)
        {
            Calendar c = Calendar.getInstance();
            year = c.get(Calendar.YEAR);
            month = c.get(Calendar.MONTH);
            day = c.get(Calendar.DAY_OF_MONTH);

            DatePickerDialog datePickerDialog = new DatePickerDialog(NewActivity.this, NewActivity.this, year, month, day);
            datePickerDialog.show();
        }
    });}
}

@Override
public void onDateSet(DatePicker view, int year, int month, int dayOfMonth)
{
    yearFinal = year;
    monthFinal = month + 1;
    dayFinal = dayOfMonth;

    Calendar c = Calendar.getInstance();
    hour = c.get(Calendar.HOUR);
    minute = c.get(Calendar.MINUTE);

    TimePickerDialog timePickerDialog = new TimePickerDialog(NewActivity.this, NewActivity.this, hour, minute, DateFormat.is24HourFormat(this));
    timePickerDialog.show();

}

@Override
public void onTimeSet(TimePicker view, int hourOfDay, int minute)
{
    hourFinal = hourOfDay;
    minuteFinal = minute;
    tv_result.setText(
            "year: " + yearFinal + "\n" +
                    "month: " + monthFinal + "\n" +
                    "day: " + dayFinal +  "\n" +
                    "hour: " + hourFinal + "\n" +
                    "minute: " + minuteFinal);
}

}

Answer 1

你的问题非常简单：

创建活动时，您正在检查是否选中了复选框。如果此值为true（但不是true），则向datePicker添加单击侦听器。所以，选择器没有点击监听器！这意味着当你＆＃34;点击＆＃34;即使选中了复选框，它也没有添加监听器。

您必须在onClick方法中移动if语句，如下所示：

编辑：

pick_date.setOnClickListener(new View.OnClickListener()
{
    @Override
    public void onClick(View view)
    {
        if((fixed_date_flag).isChecked()){
            Calendar c = Calendar.getInstance();
            year = c.get(Calendar.YEAR);
            month = c.get(Calendar.MONTH);
            day = c.get(Calendar.DAY_OF_MONTH);

            DatePickerDialog datePickerDialog = new DatePickerDialog(NewActivity.this, NewActivity.this, year, month, day);
            datePickerDialog.show();
         }
    }
});

尽管如此，我认为创建一个实现OnClickListener接口的分离cass是一个更好的选择，所以在构造函数中你可以初始化datepicker，instanciated作为这个新类的私有变量，并且你只能调用onClick方法to .show（）方法（如果选中复选框，obbiusly）

希望它有所帮助！

需要复选框以允许按下按钮 - 如果不起作用

1 个答案: