Android开发学习之路--Notification之初体验

一般当我们收到短信啊，微信啊，或者有些app的提醒，我们都会在通知栏收到一天简单的消息，然后点击消息进入到app里面，其实android中有专门的Notification的类可以完成这个工作，这里就实现下这个功能。

首先新建NotificationTest工程，然后添加一个按钮，用来触发通知，然后编写代码如下：

package com.example.jared.notificationtest;

import android.app.NotificationManager;
import android.os.Bundle;
import android.support.v4.app.NotificationCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

private Button sendNotificationBtn;

private int mId = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sendNotificationBtn = (Button)findViewById(R.id.sendNotification);
sendNotificationBtn.setOnClickListener(new myOnClickListener());
}

private class myOnClickListener implements View.OnClickListener {
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.sendNotification:
setSendNotificationBtn();
break;
default:
break;
}
}
}

public void setSendNotificationBtn () {
NotificationCompat.Builder notification = new NotificationCompat.Builder(this)
.setSmallIcon(R.mipmap.ic_launcher)
.setContentTitle("My Notification")
.setContentText("Hello Notification");
NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
manager.notify(mId, notification.build());
}
}

这里了用了NotificatonCompat.Builder来创建一个简单的Notification，setSmallIcon是指定其中的图标，setContentTitle方法是指定标题，setContentText指定内容，然后通过getSystemService获取通知的管理类，通过notify方法发送通知，其中mId是一个id号，每一个通知有其独特的通知号，不能重复。

运行效果如下所示：



接着我们来实现点击通知后跳转到对应的Activity中，然后消除这条通知。再创建一个Activity，布局如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
tools:context="com.example.jared.notificationtest.Notification">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="欢迎点击通知事件!"
android:layout_margin="20dp"
android:textSize="20dp"/>
</LinearLayout>

这里就一个textview用来显示下信息，接着编写代码如下：

package com.example.jared.notificationtest;

import android.app.NotificationManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class Notification extends AppCompatActivity {

private int mId = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_notification);
NotificationManager manager = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
manager.cancel(mId);
}
}

这里进入到Activity后就把通知清除掉，接着就是修改MainActivity代码：

package com.example.jared.notificationtest;

import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.NotificationCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

private Button sendNotificationBtn;

private int mId = 1;
private int numMessage = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sendNotificationBtn = (Button)findViewById(R.id.sendNotification);
sendNotificationBtn.setOnClickListener(new myOnClickListener());
}

private class myOnClickListener implements View.OnClickListener {
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.sendNotification:
setSendNotificationBtn();
break;
default:
break;
}
}
}

public void setSendNotificationBtn () {
NotificationCompat.Builder notification = new NotificationCompat.Builder(this)
.setSmallIcon(R.mipmap.ic_launcher)
.setContentTitle("My Notification")
.setContentText("Hello Notification")
.setNumber(++numMessage);

Intent intent = new Intent(this, Notification.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
PendingIntent.FLAG_CANCEL_CURRENT);
notification.setContentIntent(pendingIntent);

NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
manager.notify(mId, notification.build());
}
}

这里又添加了setNumber方法，主要是显示来了几条通知，比如微信中就需要知道，然后实例化了一个intent，再实例化一个pendingIntent，获取activity，在NotificationCompat.Builder里setContentIntent，之后就可以达到我们的效果，运行并点击通知如下所示：





如上所示收到了6条通知，然后点击后通知也消除了。

一般在下载歌曲啊，图片啊的时候，会有进度条表示下载的过程，这里来模拟实现下这个功能，修改MainAcitivy代码如下：

package com.example.jared.notificationtest;

import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.NotificationCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

private static final String TAG = "MainActivity";

private Button sendNotificationBtn;

private int mId = 1;
private int numMessage = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sendNotificationBtn = (Button)findViewById(R.id.sendNotification);
sendNotificationBtn.setOnClickListener(new myOnClickListener());
}

private class myOnClickListener implements View.OnClickListener {
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.sendNotification:
setSendNotificationBtn();
break;
default:
break;
}
}
}

public void setSendNotificationBtn () {
final NotificationCompat.Builder notification = new NotificationCompat.Builder(this)
.setSmallIcon(R.mipmap.ic_launcher)
.setContentTitle("Music Download")
.setContentText("burning.mp3")
.setNumber(++numMessage);

Intent intent = new Intent(this, Notification.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
PendingIntent.FLAG_CANCEL_CURRENT);
notification.setContentIntent(pendingIntent);

final NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
new Thread(
new Runnable(){
@Override
public void run() {
for(int cnt=0; cnt<=100; cnt++){
notification.setProgress(100, cnt, false);
manager.notify(mId, notification.build());
try {
Thread.sleep(200);
} catch (InterruptedException e) {
Log.d(TAG, "Sleep failure");
}
}
notification.setContentText("Download complete");
notification.setProgress(0, 0, false);
manager.notify(mId, notification.build());
}
}
).start();
}
}

这里通过setProgress方法来实现，这里开了一个Thread，当下载完成后重新设置下内容。运行结果如下：





图1显示进度条在走，图2完成了下载功能。

一般收到通知，手机都会有一段声音，加上震动，那么接下来来实现这个功能。上图，如果下载完成后，就放一段音乐并且震动，修改代码如下：

package com.example.jared.notificationtest;

import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.NotificationCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;

import java.io.File;

public class MainActivity extends AppCompatActivity {

private static final String TAG = "MainActivity";

private Button sendNotificationBtn;

private int mId = 1;
private int numMessage = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sendNotificationBtn = (Button)findViewById(R.id.sendNotification);
sendNotificationBtn.setOnClickListener(new myOnClickListener());
}

private class myOnClickListener implements View.OnClickListener {
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.sendNotification:
setSendNotificationBtn();
break;
default:
break;
}
}
}

public void setSendNotificationBtn () {
final NotificationCompat.Builder notification = new NotificationCompat.Builder(this)
.setSmallIcon(R.mipmap.ic_launcher)
.setContentTitle("Music Download")
.setContentText("burning.mp3")
.setNumber(++numMessage);

Intent intent = new Intent(this, Notification.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
PendingIntent.FLAG_CANCEL_CURRENT);
notification.setContentIntent(pendingIntent);

final NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
new Thread(
new Runnable(){
@Override
public void run() {
for(int cnt=0; cnt<=100; cnt++){
notification.setProgress(100, cnt, false);
manager.notify(mId, notification.build());
try {
Thread.sleep(100);
} catch (InterruptedException e) {
Log.d(TAG, "Sleep failure");
}
}
notification.setContentText("Download complete");
notification.setProgress(0, 0, false);
Uri soundUri = Uri.fromFile(new File("/system/media/audio/animationsounds/bootSound.ogg"));
notification.setSound(soundUri);
long[] vibrates = {0, 1000, 1000, 1000};
notification.setVibrate(vibrates);
manager.notify(mId, notification.build());
}
}
).start();
}
}

这里加上了setSound和setVibrate方法，并且需要在AndroidManifest中添加权限：

<uses-permission android:name="android.permission.VIBRATE"/>

这里的歌曲名是通过adb shell查看系统的存在的音乐：



下载到手机运行后就可以观察效果。
当然还可以控制led灯，不知为啥led灯的效果一直没有，网上翻阅很多资料也没找到问题所在，若有朋友知道，麻烦告知一二不甚感激。

notification.setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION));
long[] vibrates = {0, 1000, 1000, 1000};
notification.setVibrate(vibrates);
notification.setLights(Color.GREEN, 1000, 1000);

关于Notification基本上就学到这里了。