可以让其显示一会儿然后消失
也可以隔一段时间不断显示
第一种方式
/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.apis.app;
import com.example.android.apis.R;
import android.app.Activity;
import android.widget.Button;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;
/**
* When you push the button on this Activity, it creates a {@link Toast} object and
* using the Toast method.
* @see Toast
* @see Toast#makeText(android.content.Context,int,int)
* @see Toast#makeText(android.content.Context,java.lang.CharSequence,int)
* @see Toast#LENGTH_SHORT
* @see Toast#LENGTH_LONG
*/
public class NotifyWithText extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.notify_with_text);
Button button;
// short notification
button = (Button) findViewById(R.id.short_notify);
button.setOnClickListener(new Button.OnClickListener() {
public void onClick(View v) {
// Note that we create the Toast object and call the show() method
// on it all on one line. Most uses look like this, but there
// are other methods on Toast that you can call to configure how
// it appears.
//
// Note also that we use the version of makeText that takes a
// resource id (R.string.short_notification_text). There is also
// a version that takes a CharSequence if you must construct
// the text yourself.
Toast.makeText(NotifyWithText.this, R.string.short_notification_text,
Toast.LENGTH_SHORT).show();
}
});
// long notification
// The only difference here is that the notification stays up longer.
// You might want to use this if there is more text that they're going
// to read.
button = (Button) findViewById(R.id.long_notify);
button.setOnClickListener(new Button.OnClickListener() {
public void onClick(View v) {
Toast.makeText(NotifyWithText.this, R.string.long_notification_text,
Toast.LENGTH_LONG).show();
}
});
}
}
第二种方式
package com.example.android.apis.app;
// Need the following import to get access to the app resources, since this
// class is in a sub-package.
import com.example.android.apis.R;
import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.SystemClock;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
import java.util.Calendar;
/**
* Example of scheduling one-shot and repeating alarms. See
* {@link OneShotAlarm} for the code run when the one-shot alarm goes off, and
* {@link RepeatingAlarm} for the code run when the repeating alarm goes off.
* <h4>Demo</h4>
App/Service/Alarm Controller
<h4>Source files</h4>
<table class="LinkTable">
<tr>
<td class="LinkColumn">src/com.example.android.apis/app/AlarmController.java</td>
<td class="DescrColumn">The activity that lets you schedule alarms</td>
</tr>
<tr>
<td class="LinkColumn">src/com.example.android.apis/app/OneShotAlarm.java</td>
<td class="DescrColumn">This is an intent receiver that executes when the
one-shot alarm goes off</td>
</tr>
<tr>
<td class="LinkColumn">src/com.example.android.apis/app/RepeatingAlarm.java</td>
<td class="DescrColumn">This is an intent receiver that executes when the
repeating alarm goes off</td>
</tr>
<tr>
<td class="LinkColumn">/res/any/layout/alarm_controller.xml</td>
<td class="DescrColumn">Defines contents of the screen</td>
</tr>
</table>
*/
public class AlarmController extends Activity {
Toast mToast;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.alarm_controller);
// Watch for button clicks.
Button button = (Button)findViewById(R.id.one_shot);
button.setOnClickListener(mOneShotListener);
button = (Button)findViewById(R.id.start_repeating);
button.setOnClickListener(mStartRepeatingListener);
button = (Button)findViewById(R.id.stop_repeating);
button.setOnClickListener(mStopRepeatingListener);
}
private OnClickListener mOneShotListener = new OnClickListener() {
public void onClick(View v) {
// When the alarm goes off, we want to broadcast an Intent to our
// BroadcastReceiver. Here we make an Intent with an explicit class
// name to have our own receiver (which has been published in
// AndroidManifest.xml) instantiated and called, and then create an
// IntentSender to have the intent executed as a broadcast.
Intent intent = new Intent(AlarmController.this, OneShotAlarm.class);
PendingIntent sender = PendingIntent.getBroadcast(AlarmController.this,
0, intent, 0);
// We want the alarm to go off 30 seconds from now.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.add(Calendar.SECOND, 30);
// Schedule the alarm!
AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
am.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), sender);
// Tell the user about what we did.
if (mToast != null) {
mToast.cancel();
}
mToast = Toast.makeText(AlarmController.this, R.string.one_shot_scheduled,
Toast.LENGTH_LONG);
mToast.show();
}
};
private OnClickListener mStartRepeatingListener = new OnClickListener() {
public void onClick(View v) {
// When the alarm goes off, we want to broadcast an Intent to our
// BroadcastReceiver. Here we make an Intent with an explicit class
// name to have our own receiver (which has been published in
// AndroidManifest.xml) instantiated and called, and then create an
// IntentSender to have the intent executed as a broadcast.
// Note that unlike above, this IntentSender is configured to
// allow itself to be sent multiple times.
Intent intent = new Intent(AlarmController.this, RepeatingAlarm.class);
PendingIntent sender = PendingIntent.getBroadcast(AlarmController.this,
0, intent, 0);
// We want the alarm to go off 30 seconds from now.
long firstTime = SystemClock.elapsedRealtime();
firstTime += 15*1000;
// Schedule the alarm!
AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
am.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP,
firstTime, 15*1000, sender);
// Tell the user about what we did.
if (mToast != null) {
mToast.cancel();
}
mToast = Toast.makeText(AlarmController.this, R.string.repeating_scheduled,
Toast.LENGTH_LONG);
mToast.show();
}
};
private OnClickListener mStopRepeatingListener = new OnClickListener() {
public void onClick(View v) {
// Create the same intent, and thus a matching IntentSender, for
// the one that was scheduled.
Intent intent = new Intent(AlarmController.this, RepeatingAlarm.class);
PendingIntent sender = PendingIntent.getBroadcast(AlarmController.this,
0, intent, 0);
// And cancel the alarm.
AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
am.cancel(sender);
// Tell the user about what we did.
if (mToast != null) {
mToast.cancel();
}
mToast = Toast.makeText(AlarmController.this, R.string.repeating_unscheduled,
Toast.LENGTH_LONG);
mToast.show();
}
};
}