如何从日期选择器更改日期格式（日历视图）

Question

我是新手android开发者。

现在，我尝试将日期格式从m / d / yyyy更改为mmddyyyy。

这是参考链接：http://www.thaicreate.com/mobile/android-calendarview.html

希望有人帮助我。

抱歉我的英语不好。

myCalendarView.java

package com.myapp;

import android.os.Bundle;
import android.app.Activity;
import android.widget.CalendarView;
import android.content.Intent;

public class myCalendarView  extends Activity {
	
    private int mYear;
    private int mMonth;
    private int mDay;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        CalendarView calendar = new CalendarView(this);
        calendar.setOnDateChangeListener(mDateSetListener);
        setContentView(calendar);

    }

    // the callback received when the user "sets" the date in the dialog
    private CalendarView.OnDateChangeListener mDateSetListener =
        new CalendarView.OnDateChangeListener() {

        public void onSelectedDayChange(CalendarView view, int year, 
                int monthOfYear, int dayOfMonth) {
            mYear = year;
            mMonth = monthOfYear;
            mDay = dayOfMonth;
            String selectedDate = new StringBuilder().append(mMonth + 1).append("-").append(mDay).append("-")
            .append(mYear).append(" ").toString();

            Bundle b = new Bundle();
            b.putString("dateSelected", selectedDate);

            //Add the set of extended data to the intent and start it
            Intent intent = new Intent();
            intent.putExtras(b);
            setResult(RESULT_OK,intent);       
            finish();
        }
    };

}

MainActivity.java

package com.myapp;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.Button;
import android.widget.EditText;
import android.view.View;
import java.util.Calendar;
import android.content.Intent;

public class MainActivity extends Activity {
	
    private EditText editT1;
    private Button btn1;

    private int mYear;
    private int mMonth;
    private int mDay;

    static final int CALENDAR_VIEW_ID = 1;
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
       
        
        // editText1
        editT1 = (EditText) findViewById(R.id.editText1);
        
        // button1
        btn1 = (Button) findViewById(R.id.button1);

        // add a click listener to the button
        btn1.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                Intent intent = new Intent(MainActivity.this, myCalendarView.class); 
                startActivityForResult(intent,CALENDAR_VIEW_ID); 
            }
        });
        
        // get the current date
        final Calendar c = Calendar.getInstance();
        mYear = c.get(Calendar.YEAR);
        mMonth = c.get(Calendar.MONTH);
        mDay = c.get(Calendar.DAY_OF_MONTH);

        // display the current date
        updateCurrentDate();
		
    }

    // updates the date we display in the TextView
    private void updateCurrentDate() {
    	editT1.setText(
            new StringBuilder()
                    // Month is 0 based so add 1
                    .append(mMonth + 1).append("-")
                    .append(mDay).append("-")
                    .append(mYear).append(" "));
    }
    
    protected void onActivityResult(int requestCode, int resultCode, Intent data)
    {
        switch(requestCode) {
        case CALENDAR_VIEW_ID: 
            if (resultCode == RESULT_OK) {

                Bundle bundle = data.getExtras();
                editT1.setText(bundle.getString("dateSelected"));
                break;
            }
        }

    }
    
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
    
}

Answer 1

您可以像

一样进行转换

DateFormat formatter = new SimpleDateFormat("MM/dd/yy");
Date date = (Date)formatter.parse("5/1/12");

formatter = new SimpleDateFormat("MM/dd/yyyy");
date = (Date)formatter.format(date);

如果你想更改日期选择器，那么你可以使用这个

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

int month = monthOfYear + 1;
String formattedMonth = "" + month;
String formattedDayOfMonth = "" + dayOfMonth;

if(month < 10){

    formattedMonth = "0" + month;
}
if(dayOfMonth < 10){

    formattedDayOfMonth = "0" + dayOfMonth;
}
searchText.setText(formattedDayOfMonth + "/" + formattedMonth + "/" + year);
}

Answer 2

如上所述，您可能最好使用简单的日期格式。

这是一个教程，将显示输出的差异。

https://www.ntu.edu.sg/home/ehchua/programming/java/DateTimeCalendar.html

Answer 3

try {
    SimpleDateFormat inputDate = new SimpleDateFormat("d/M/yyyy", Locale.US);
    SimpleDateFormat outputDate = new SimpleDateFormat("MMddyyyy", Locale.US);

    String date = outputDate.format(inputDate.parse("5/2/1993"));


} catch (ParseException e) {
    e.printStackTrace();
}

Answer 4

用户根据您的日期格式解析日期的方法..

public static String parsePickerDate(int Year, int Month, int day) {

    String sYear = String.valueOf(Year);
    String sMonth = String.valueOf((Month + 1));
    String sDay = String.valueOf(day);

    if (sDay.length() == 1)
        sDay = "0" + sDay;

    if (sMonth.length() == 1)
        sMonth = "0" + sMonth;

    if (sDay.length() == 1)
        sDay = "0" + sDay;

    return sYear + "-" + sMonth + "-" + sDay;
}