android - Edittext 无法从日期选择器中获取用户确定的日期

Question

我想在单击图像按钮时弹出一个日期选择器对话框，然后用户选择的日期将显示在编辑文本字段中。我按照Android开发人员的指导通过DialogFragment使用，成功弹出了日期选择器对话框。用户可以在对话框中选择日期，但是当用户按下设置按钮时它会崩溃。

事实上，我怀疑这是 onDateSet 中 LayoutInflater 中的 getContext() 的问题，因为有评论说“调用所需的 API 级别 23(当前 API:12)”，但我无法弄清楚如何修复它。

这是Android开发者推荐调用getContext()来获取active Context的，不知道为什么会出现这个问题。

我尝试使用@TargetApi，但它说这仅用于方法。

谁能告诉我我的代码哪里有问题？

合乎逻辑的陈述:java.lang.NoSuchMethodError:com.test.testapplication.DatePickerFragment.getContext

日期选择器 fragment

public class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {


final Calendar calendar = Calendar.getInstance();
int YEAR;
int MONTH;
int DAY;

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {

    YEAR = calendar.get(Calendar.YEAR);
    MONTH = calendar.get(Calendar.MONTH);
    DAY = calendar.get(Calendar.DAY_OF_MONTH);

    return new DatePickerDialog(getActivity(), this, YEAR, MONTH, DAY);
}

@Override
public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {

    YEAR = year;
    MONTH = monthOfYear;
    DAY = dayOfMonth;

    String dateFormat = "MM/dd/yy";
    SimpleDateFormat sdf = new SimpleDateFormat(dateFormat, Locale.CHINESE);

    View fragment = LayoutInflater.from(getContext()).inflate(R.layout.activity_datepickerdialogfragment, null);
    EditText editText = (EditText) fragment.findViewById(R.id.edittext);
    editText.setText(sdf.format(calendar.getTime()));
}
}

主要 Activity

public class DPDFActivity extends FragmentActivity {

EditText editText;
ImageButton btn;
DialogFragment datePickerFragment;

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

    editText = (EditText) findViewById(R.id.edittext);
    btn = (ImageButton) findViewById(R.id.btn);

    btn.setOnClickListener(new showDateDialog());
}

public class showDateDialog implements View.OnClickListener {
    @Override
    public void onClick(View v) {
        datePickerFragment = new DatePickerFragment();
        datePickerFragment.show(getFragmentManager(), "DatePicker");
    }
}
}

Answer 1

在你的 Activity 中创建日期选择器类作为静态的，例如我在我的 fragment 中做了类似的事情。

public static class DatePickerFragment extends DialogFragment
        implements DatePickerDialog.OnDateSetListener {
    int currentYear;

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the current date as the default date in the picker
        final Calendar c = Calendar.getInstance();
        currentYear = c.get(Calendar.YEAR);
        int month = c.get(Calendar.MONTH);
        int day = c.get(Calendar.DAY_OF_MONTH);

        // Create a new instance of DatePickerDialog and return it
        return new DatePickerDialog(getActivity(), this, currentYear, month, day);
    }

    public void onDateSet(DatePicker view, int year, int month, int day) {
        if(currentYear-year >=15) {
            CharSequence strDate = null;
            Calendar chosenDate = Calendar.getInstance();
            chosenDate.setTimeInMillis(0);
            chosenDate.set(year, month, day);
            Date date = chosenDate.getTime();
            SimpleDateFormat dateFormatter = new SimpleDateFormat(
                    "yyyy-MM-dd");
            strDate = dateFormatter.format(date);

            btnDOB.setText(strDate);
        }
        else
        {
            Toast.makeText(view.getContext(),"Selected Year should be mininmum 15 year ago from current year. Please try again.",Toast.LENGTH_LONG).show();
        }
    }
}

在任何 methon(类级别)之外的 Activity 中定义 edittext

private static EditText meditText;

仅在 Activity oncreate() 中使用 findById() 方法，稍后可以更新。