android - 将所选日期从 DatePickerDialog 复制到主页的 Edittext 框中

Question

我正在按照此链接创建一个 DatePickerDialog 并将所选日期复制到 Editext 字段。但是，我无法理解如何做到这一点，因为无论我在 onDateSet 方法中做什么，它都无法识别。如果有人好心帮忙。

主要 XML：

<EditText
                android:id="@+id/add_datepurchased"
                android:inputType="date"
                android:onClick="showdate" />

主类：

EditText datpurchased;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_add_entry);
        // Show the Up button in the action bar.
        setupActionBar();

        datpurchased = (EditText) findViewById(R.id.add_datepurchased);
    }
public void showdate(View v) {
        DialogFragment newFragment = new DatePickerFragment();
        newFragment.show(getFragmentManager(), "datePicker");
    }

DatePickerFragment 类：

public class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState){
        final Calendar c=Calendar.getInstance();
        int year=c.get(Calendar.YEAR);
        int month=c.get(Calendar.MONTH);
        int day=c.get(Calendar.DAY_OF_MONTH);
        return new DatePickerDialog(getActivity(), this, year, month, day);
    }

    public void onDateSet(DatePicker view, int year, int month, int day){
        EditText datpurchased = (EditText) findViewById(R.id.add_datepurchased); // GIVES ERROR
        datpurchased.setText(year+"-"+(month+1)+"-"+day);
    }
}

Answer 1

您应该在 onCreate() 中初始化 EditText