我正在尝试在Android中创建提醒，我们可以在其中设置通知，我们可以选择日期和时间并相应地设置提醒。我无法检测到我的错误。请帮助...
MainActivity.java
public class MainActivity extends Activity {
// This is a handle so that we can call methods on our service
private ScheduleClient scheduleClient;
// This is the date picker used to select the date for our notification
private DatePicker picker;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Create a new service client and bind our activity to this service
scheduleClient = new ScheduleClient(this);
scheduleClient.doBindService();
// Get a reference to our date picker
picker = (DatePicker) findViewById(R.id.scheduleTimePicker);
}
/**
* This is the onClick called from the XML to set a new notification
*/
public void onDateSelectedButtonClick(View v){
// Get the date from our datepicker
int day = picker.getDayOfMonth();
int month = picker.getMonth();
int year = picker.getYear();
// Create a new calendar set to the date chosen
// we set the time to midnight (i.e. the first minute of that day)
Calendar c = Calendar.getInstance();
c.set(year, month, day);
c.set(Calendar.HOUR_OF_DAY, 0);
c.set(Calendar.MINUTE, 0);
c.set(Calendar.SECOND, 0);
// Ask our service to set an alarm for that date, this activity talks to the client that talks to the service
scheduleClient.setAlarmForNotification(c);
// Notify the user what they just did
Toast.makeText(this, "Notification set for: "+ day +"/"+ (month+1) +"/"+ year, Toast.LENGTH_SHORT).show();
}
@Override
protected void onStop() {
// When our activity is stopped ensure we also stop the connection to the service
// this stops us leaking our activity into the system *bad*
if(scheduleClient != null)
scheduleClient.doUnbindService();
super.onStop();
}
}
activity_main.xml中
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
<DatePicker
android:id="@+id/scheduleTimePicker"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<Button
android:id="@+id/selectButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:onClick="onDateSelectedButtonClick"
android:text="Set notification for this date" />
</LinearLayout>
ScheduleClient.java：
public class ScheduleClient {
// The hook into our service
private ScheduleService mBoundService;
// The context to start the service in
private Context mContext;
// A flag if we are connected to the service or not
private boolean mIsBound;
public ScheduleClient(Context context) {
mContext = context;
}
/**
* Call this to connect your activity to your service
*/
public void doBindService() {
// Establish a connection with our service
mContext.bindService(new Intent(mContext, ScheduleService.class), mConnection, Context.BIND_AUTO_CREATE);
mIsBound = true;
}
/**
* When you attempt to connect to the service, this connection will be called with the result.
* If we have successfully connected we instantiate our service object so that we can call methods on it.
*/
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
// This is called when the connection with our service has been established,
// giving us the service object we can use to interact with our service.
mBoundService = ((ScheduleService.ServiceBinder) service).getService();
}
public void onServiceDisconnected(ComponentName className) {
mBoundService = null;
}
};
/**
* Tell our service to set an alarm for the given date
* @param c a date to set the notification for
*/
public void setAlarmForNotification(Calendar c){
mBoundService.setAlarm(c);
}
/**
* When you have finished with the service call this method to stop it
* releasing your connection and resources
*/
public void doUnbindService() {
if (mIsBound) {
// Detach our existing connection.
mContext.unbindService(mConnection);
mIsBound = false;
}
}
ScheduleService.java
public class ScheduleService extends Service {
/**
* Class for clients to access
*/
public class ServiceBinder extends Binder {
ScheduleService getService() {
return ScheduleService.this;
}
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i("ScheduleService", "Received start id " + startId + ": " + intent);
// We want this service to continue running until it is explicitly stopped, so return sticky.
return START_STICKY;
}
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
// This is the object that receives interactions from clients. See
private final IBinder mBinder = new ServiceBinder();
/**
* Show an alarm for a certain date when the alarm is called it will pop up a notification
*/
public void setAlarm(Calendar c) {
// This starts a new thread to set the alarm
// You want to push off your tasks onto a new thread to free up the UI to carry on responding
new AlarmTask(this, c).run();
}
}
}
AlarmTask.java
public class AlarmTask implements Runnable{
// The date selected for the alarm
private final Calendar date;
// The android system alarm manager
private final AlarmManager am;
// Your context to retrieve the alarm manager from
private final Context context;
public AlarmTask(Context context, Calendar date) {
this.context = context;
this.am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
this.date = date;
}
@Override
public void run() {
// Request to start are service when the alarm date is upon us
// We don't start an activity as we just want to pop up a notification into the system bar not a full activity
Intent intent = new Intent(context, NotifyService.class);
intent.putExtra(NotifyService.INTENT_NOTIFY, true);
PendingIntent pendingIntent = PendingIntent.getService(context, 0, intent, 0);
// Sets an alarm - note this alarm will be lost if the phone is turned off and on again
am.set(AlarmManager.RTC, date.getTimeInMillis(), pendingIntent);
}
}
NotifyService.java
public class NotifyService extends Service {
/**
* Class for clients to access
*/
public class ServiceBinder extends Binder {
NotifyService getService() {
return NotifyService.this;
}
}
// Unique id to identify the notification.
private static final int NOTIFICATION = 123;
// Name of an intent extra we can use to identify if this service was started to create a notification
public static final String INTENT_NOTIFY = "com.blundell.tut.service.INTENT_NOTIFY";
// The system notification manager
private NotificationManager mNM;
@Override
public void onCreate() {
Log.i("NotifyService", "onCreate()");
mNM = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i("LocalService", "Received start id " + startId + ": " + intent);
// If this service was started by out AlarmTask intent then we want to show our notification
if(intent.getBooleanExtra(INTENT_NOTIFY, false))
showNotification();
// We don't care if this service is stopped as we have already delivered our notification
return START_NOT_STICKY;
}
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
// This is the object that receives interactions from clients
private final IBinder mBinder = new ServiceBinder();
/**
* Creates a notification and shows it in the OS drag-down status bar
*/
private void showNotification() {
// This is the 'title' of the notification
CharSequence title = "Alarm!!";
// This is the icon to use on the notification
int icon = R.drawable.ic_dialog_alert;
// This is the scrolling text of the notification
CharSequence text = "Your notification time is upon us.";
// What time to show on the notification
long time = System.currentTimeMillis();
Notification notification = new Notification(icon, text, time);
// The PendingIntent to launch our activity if the user selects this notification
PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, SecondActivity.class), 0);
// Set the info for the views that show in the notification panel.
notification.setLatestEventInfo(this, title, text, contentIntent);
// Clear the notification when it is pressed
notification.flags |= Notification.FLAG_AUTO_CANCEL;
// Send the notification to the system.
mNM.notify(NOTIFICATION, notification);
// Stop the service when we are finished
stopSelf();
}
}
AndroidManifest.java
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.reminder"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="19" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.reminder.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.example.reminder.SecondActivity"
android:label="@string/title_activity_second" >
</activity>
<service android:name=".service.ScheduleService" />
<service android:name=".service.NotifyService" />
</application>
</manifest>
Logat：
08-11 07:01:02.900: E/AndroidRuntime(817): FATAL EXCEPTION: main
08-11 07:01:02.900: E/AndroidRuntime(817): Process: com.example.reminder, PID: 817
08-11 07:01:02.900: E/AndroidRuntime(817): java.lang.IllegalStateException: Could not execute method of the activity
08-11 07:01:02.900: E/AndroidRuntime(817): at android.view.View$1.onClick(View.java:3823)
08-11 07:01:02.900: E/AndroidRuntime(817): at android.view.View.performClick(View.java:4438)
08-11 07:01:02.900: E/AndroidRuntime(817): at android.view.View$PerformClick.run(View.java:18422)
08-11 07:01:02.900: E/AndroidRuntime(817): at android.os.Handler.handleCallback(Handler.java:733)
08-11 07:01:02.900: E/AndroidRuntime(817): at android.os.Handler.dispatchMessage(Handler.java:95)
08-11 07:01:02.900: E/AndroidRuntime(817): at android.os.Looper.loop(Looper.java:136)
08-11 07:01:02.900: E/AndroidRuntime(817): at android.app.ActivityThread.main(ActivityThread.java:5017)
08-11 07:01:02.900: E/AndroidRuntime(817): at java.lang.reflect.Method.invokeNative(Native Method)
08-11 07:01:02.900: E/AndroidRuntime(817): at java.lang.reflect.Method.invoke(Method.java:515)
08-11 07:01:02.900: E/AndroidRuntime(817): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
08-11 07:01:02.900: E/AndroidRuntime(817): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
08-11 07:01:02.900: E/AndroidRuntime(817): at dalvik.system.NativeStart.main(Native Method)
08-11 07:01:02.900: E/AndroidRuntime(817): Caused by: java.lang.reflect.InvocationTargetException
08-11 07:01:02.900: E/AndroidRuntime(817): at java.lang.reflect.Method.invokeNative(Native Method)
08-11 07:01:02.900: E/AndroidRuntime(817): at java.lang.reflect.Method.invoke(Method.java:515)
08-11 07:01:02.900: E/AndroidRuntime(817): at android.view.View$1.onClick(View.java:3818)
08-11 07:01:02.900: E/AndroidRuntime(817): ... 11 more
08-11 07:01:02.900: E/AndroidRuntime(817): Caused by: java.lang.NullPointerException
08-11 07:01:02.900: E/AndroidRuntime(817): at com.example.reminder.ScheduleClient.setAlarmForNotification(ScheduleClient.java:54)
08-11 07:01:02.900: E/AndroidRuntime(817): at com.example.reminder.MainActivity.onDateSelectedButtonClick(MainActivity.java:46)
08-11 07:01:02.900: E/AndroidRuntime(817): ... 14 more
请建议......