Question

这是我创建的TimePicker类的代码

picker.java

package com.example.abhijeet.todo;

import android.app.Dialog;
import android.app.DialogFragment;
import android.app.TimePickerDialog;
import android.content.Context;
import android.os.Bundle;
import android.text.format.DateFormat;
import android.view.View;
import android.widget.EditText;
import android.widget.TimePicker;

import java.util.Calendar;

/**
 * Created by Abhijeet on 9/6/2017.
 */

public class Picker extends DialogFragment implements TimePickerDialog.OnTimeSetListener {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        // Use the current time as the default values for the picker
        final Calendar c = Calendar.getInstance();
        int hour = c.get(Calendar.HOUR_OF_DAY);
        int minute = c.get(Calendar.MINUTE);

        // Create a new instance of TimePickerDialog and return it
        return new TimePickerDialog(getActivity(), this, hour, minute,
                DateFormat.is24HourFormat(getActivity()));
    }



    @Override
    public void onTimeSet(TimePicker timePicker, int i, int i1) {
        //Creating a View object because this class do not extend from activity class so no findviewbyid() method is present
       View v =View.inflate(*  ?   *,R.layout.activity_editor,null);  //HERE
        //Displaying the user selected time on the Edit Text view
        EditText edittime = (EditText) v.findViewById(R.id.time_editext_field);


    }
}

我试图在编辑文本框中显示通过选择器选择的时间。我无法为争论找到合适的背景。

我已经阅读了答案here，它解释了上下文的不同用法，但这似乎对我没有帮助。

感谢Advance中的帮助。

Answer 1

只需致电getContext()

由于DialogFragment是Fragment的孩子。因此，可以在DialogFragment中调用所有Fragment类方法。

喜欢这个

@Override
    public void onTimeSet(TimePicker timePicker, int i, int i1) {
        //Creating a View object because this class do not extend from activity class so no findviewbyid() method is present
       View v =View.inflate(getContext() ,R.layout.activity_editor,null);  //HERE
        //Displaying the user selected time on the Edit Text view
        EditText edittime = (EditText) v.findViewById(R.id.time_editext_field);
    }

您也可以调用getActivity()方法。如果您要定位到比23更旧的API：

@Override
    public void onTimeSet(TimePicker timePicker, int i, int i1) {
        //Creating a View object because this class do not extend from activity class so no findviewbyid() method is present
       View v =View.inflate(getActivity() ,R.layout.activity_editor,null);  //HERE
        //Displaying the user selected time on the Edit Text view
        EditText edittime = (EditText) v.findViewById(R.id.time_editext_field);
    }

Answer 2

无论何时使用。 Activity - ＆gt; getApplicationContext()，Fragment - ＆gt; getActivity()，Adapter - ＆gt; getContext()

什么可以用作上下文的第一个参数？

2 个答案: