Question

我试图让用户在点击按钮时选择一个日期并显示3个滚轮来选择日，月和年它然后将设置用户选择的任何内容到文本视图，此时我点击按钮什么都没发生只是空点击任何帮助将不胜感激。我将在下面插入代码。我收到了这行代码的错误。

fragment.show(getSupportFragmentManager(), "date");

Datepicker代码

public void datePicker(View view) {
        DatePickerFragment fragment = new DatePickerFragment();
        fragment.show(getSupportFragmentManager(), "date");
    }

    public void setDate(final Calendar calendar) {
        final DateFormat dateFormat = DateFormat.getDateInstance(DateFormat.MEDIUM);
        ((TextView) findViewById(R.id.dateSet)).setText(dateFormat.format(calendar.getTime()));
    }

    @Override
    public void onDateSet(DatePicker view, int year, int month, int dayOfMonth) {
        Calendar cal = new GregorianCalendar(year, month, dayOfMonth);
        setDate(cal);
    }

    public static class DatePickerFragment extends DialogFragment {

        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(),
                    (DatePickerDialog.OnDateSetListener)
                            getActivity(), year, month, day);
        }


        public void show(FragmentManager supportFragmentManager, String date) {
        }
    }

}

按钮和TextView代码：

<TextView
        android:text=""
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/dateSet"
        android:layout_above="@+id/Category"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_marginBottom="11dp" />

    <Button
        android:text="Pick Date"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/dateSet"
        android:layout_alignLeft="@+id/incomeDate"
        android:layout_alignStart="@+id/incomeDate"
        android:layout_marginBottom="17dp"
        android:onClick="datePicker"
        android:id="@+id/picDate" />

错误：

Error:(135, 17) error: no suitable method found for show(android.support.v4.app.FragmentManager,String)
method DialogFragment.show(android.app.FragmentManager,String) is not applicable
(argument mismatch; android.support.v4.app.FragmentManager cannot be converted to android.app.FragmentManager)
method DialogFragment.show(FragmentTransaction,String) is not applicable
(argument mismatch; android.support.v4.app.FragmentManager cannot be converted to FragmentTransaction)

Answer 1

错误有点令人困惑，特别是如果你只关注类名并忽略他们的包。问题是支持库使用相同的类名作为本机API。要解决此问题，请仔细检查应使用支持库的类的导入。例如

import android.support.v4.app.DialogFragment

很可能你有

import android.app.DialogFragment

这是Native API中的一个类。尽管这两个类具有相同的名称，但它们是两种不同的类型，因为它们位于不同的包中。

Android Studio日历选择器

1 个答案: