TextView不会使用datepicker选择的新日期进行更新

Question

我设置了两个日期选择器（即签入和签出）。我第一次运行应用程序时一切都很好，我点击的日期显示在TextView.But而不运行应用程序第二次当我尝试单击“检入”按钮时，日期在TextView中没有变化。但日期在LogCat中发生了变化。同时Check Out按钮第一次正常工作，第二次正常工作（不再运行应用程序）。请解决我的问题。

这是我的代码：

import java.util.Calendar;
import android.app.Activity;
import android.app.DatePickerDialog;
import android.app.Dialog;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.TextView;
import android.widget.Toast;

import java.util.Calendar;


public class MainActivity extends ActionBarActivity {
Button checkIn, checkOut, checkavailability;
TextView displayCheckIn, displayCheckOut;
int year, month, day;
static final int DATE_DIALOG_ID = 1;
static final int DATE_DIALOG_ID2 = 2;
int cur = 0;
String chidate, chodate;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    checkIn = (Button) findViewById(R.id.checkInBtn);
    checkOut = (Button) findViewById(R.id.checkOutBtn);
    displayCheckIn = (TextView) findViewById(R.id.displayCheckIntv);
    displayCheckOut = (TextView) findViewById(R.id.displayCheckOuttv);
    checkavailability = (Button) findViewById(R.id.checkAvailabilityBtn);
    setCurrentDateOnView();//declaring a method to display the current date in the opening
    addListenerOnButton();
}

//settin the current date in the opening page
public void setCurrentDateOnView() {
    Calendar today = Calendar.getInstance();
    year = today.get(Calendar.YEAR);
    month = today.get(Calendar.MONTH);
    day = today.get(Calendar.DAY_OF_MONTH);
    //displaying current date in the check in textView
    displayCheckIn.setText(year + "-" + (month + 1) + "-" + day);
    //displaying the current date in check out textView by getting the text from the check in view
    displayCheckOut.setText(year + "-" + (month + 1) + "-" + day);
}

public void addListenerOnButton() {
    checkIn.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            showDialog(DATE_DIALOG_ID);
        }
    });
    checkOut.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            showDialog(DATE_DIALOG_ID2);
        }
    });
    checkavailability.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            //checkAvailability();
        }
    });
}

@Override
protected Dialog onCreateDialog(int id) {
    switch (id) {
        case DATE_DIALOG_ID:
            System.out.println("onCreate Dialog  :" + id);
            cur = DATE_DIALOG_ID;
            //Displaying the Date Picker Dialog on the screen with today's date
            return new DatePickerDialog(this, datePickerListener, year, month, day);


        case DATE_DIALOG_ID2:
            System.out.println("onCreateDialog   :" + id);
            cur = DATE_DIALOG_ID2;
            return new DatePickerDialog(this, datePickerListener, year, month, day);

    }
    return null;
}

private DatePickerDialog.OnDateSetListener datePickerListener = new DatePickerDialog.OnDateSetListener() {
    @Override
    public void onDateSet(DatePicker view, int syear, int monthOfYear, int dayOfMonth) {
        year = syear;
        month = monthOfYear;
        day = dayOfMonth;
        if (cur == DATE_DIALOG_ID) {
            displayCheckIn.setText(year + "-" + (month + 1) + "-" + day);
            chidate = displayCheckIn.getText().toString();
            System.out.println(chidate);
            //Toast.makeText(getApplicationContext(),chidate,Toast.LENGTH_LONG).show();
        } else {
            displayCheckOut.setText(year + "-" + (month + 1) + "-" + day);
            chodate = displayCheckOut.getText().toString();
            System.out.println(chodate);
            //Toast.makeText(getApplicationContext(),chodate,Toast.LENGTH_LONG).show();
        }


    }
};

//这是我每次都要检查Checkin日期的代码。

/*public void checkAvailability() {
    String[] datesin = {"2014-12-16", "2014-12-17", "2014-12-18"};
    for (int j = 0; j < datesin.length; j++) {
        if (datesin[j].equals(chidate)) {
            Toast.makeText(getApplicationContext(), "Room Not Available", Toast.LENGTH_LONG).show();
            break;
        } else
            Toast.makeText(getApplicationContext(), "Room Available", Toast.LENGTH_LONG).show();
    }
}*/

}

我的XML是：

<RelativeLayout 
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity"
>


<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/displayCheckIntv"
    android:text="Hiiiiiiiiiiiiiiiiiiiii"
    android:layout_toEndOf="@+id/datePicker"
    android:layout_alignTop="@+id/datePicker"
    android:layout_centerHorizontal="true" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="CheckIn"
    android:id="@+id/checkInBtn"

    android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Check Out"
    android:id="@+id/checkOutBtn"
    android:layout_marginTop="48dp"
    android:layout_below="@+id/checkInBtn"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Check Out"
    android:id="@+id/displayCheckOuttv"
    android:layout_toEndOf="@+id/checkOutBtn"
    android:layout_alignBottom="@+id/checkOutBtn"
    android:layout_centerHorizontal="true" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Check Availability"
    android:id="@+id/checkAvailabilityBtn"
    android:layout_centerVertical="true"
    android:layout_alignLeft="@+id/displayCheckOuttv"
    android:layout_alignStart="@+id/displayCheckOuttv" />

</RelativeLayout>