ダイアログにカレンダービューを表示しようとしています。以下はコードです。ダイアログを起動するボタンをクリックすると、アプリがクラッシュしNullPointerExceptionます。この場合のnullポインターは、次の行で作成されている「cal」変数です。
cal =（CalendarView）calenderDialog.findViewById（R.id.calendarView1）;
package com.android.filllip.ToDo;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.v4.app.DialogFragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.widget.CalendarView;
import android.widget.CalendarView.OnDateChangeListener;
public class CalendarDialog extends DialogFragment {
NoticeDialogListener mListener;
CalendarView cal;
static int mYear;
static int mMonth;
static int mDay;
static final String tag = "Calendar pop up";
interface NoticeDialogListener {
public void onDialogPositiveClick(DialogFragment dialog);
public void onDialogNegativeClick(DialogFragment dialog);
public void showTheSelectedDate();
}
*public Dialog onCreateDialog(Bundle onSaveInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
LayoutInflater inflater = getActivity().getLayoutInflater();
builder.setView(inflater.inflate(R.layout.calendarpopup, null));
builder.setNegativeButton("Set ",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int id) {
mListener.onDialogPositiveClick(CalendarDialog.this);
}
});
builder.setPositiveButton("Cancel",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int id) {
mListener.onDialogPositiveClick(CalendarDialog.this);
}
});
AlertDialog calendarDialog = builder.create();
cal = (CalendarView)calendarDialog.findViewById(R.id.calendarView1);
Log.d(tag,"calender value is "+cal);
cal.setOnDateChangeListener(new OnDateChangeListener(){
@Override
public void onSelectedDayChange(CalendarView view, int year,
int month, int dayOfMonth) {
// TODO Auto-generated method stub
Log.d(tag,mYear+": year");
Log.d(tag,mMonth+": month");
Log.d(tag,mDay+": day");
mYear = year;
mMonth = month;
mDay = dayOfMonth;
}
});
return calendarDialog;
}*
public void onAttach(Activity activity) {
super.onAttach(activity);
// Verify that the host activity implements the callback interface
try {
// Instantiate the NoticeDialogListener so we can send events to the
// host
mListener = (NoticeDialogListener) activity;
} catch (ClassCastException e) {
// The activity doesn't implement the interface, throw exception
throw new ClassCastException(activity.toString()
+ " must implement NoticeDialogListener");
}
}
}
私のレイアウトファイルは：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<CalendarView
android:id="@+id/calendarView1"
android:layout_width="match_parent"
android:layout_height="300dp"
/>
</RelativeLayout>
logcatトレース：
03-25 17:10:01.531: E/AndroidRuntime(3102): FATAL EXCEPTION: main
03-25 17:10:01.531: E/AndroidRuntime(3102): java.lang.NullPointerException
03-25 17:10:01.531: E/AndroidRuntime(3102): at com.android.filllip.ToDo.CalendarDialog.onCreateDialog(CalendarDialog.java:61)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.support.v4.app.DialogFragment.getLayoutInflater(DialogFragment.java:295)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:429)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.os.Handler.handleCallback(Handler.java:605)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.os.Handler.dispatchMessage(Handler.java:92)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.os.Looper.loop(Looper.java:137)
03-25 17:10:01.531: E/AndroidRuntime(3102): at android.app.ActivityThread.main(ActivityThread.java:4511)
03-25 17:10:01.531: E/AndroidRuntime(3102): at java.lang.reflect.Method.invokeNative(Native Method)
03-25 17:10:01.531: E/AndroidRuntime(3102): at java.lang.reflect.Method.invoke(Method.java:511)
03-25 17:10:01.531: E/AndroidRuntime(3102): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:976)
03-25 17:10:01.531: E/AndroidRuntime(3102): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:743)
03-25 17:10:01.531: E/AndroidRuntime(3102): at dalvik.system.NativeStart.main(Native Method)