Android通知

通知能提醒我们。Android提供了强大的通知功能，现在创建一个简单的通知测试项目：
NotificationTest

添加依赖

通知需要依赖support-compat，以后可能更多的使用AndroidX。

dependencies {    implementation "com.android.support:support-compat:28.0.0"}

创建活动

要创建两个活动，一个是主活动，一个是结果活动，用来显示点击通知后的结果页。

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.notificationtest">    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:roundIcon="@mipmap/ic_launcher_round"        android:supportsRtl="true"        android:theme="@style/AppTheme">        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            intent-filter>        activity>        <activity android:name=".ResultActivity"            android:launchMode="singleTask"            android:taskAffinity=""            android:excludeFromRecents="true"            android:parentActivityName=".MainActivity">        activity>    application>manifest>

布局activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical"    android:layout_width="match_parent"    android:layout_height="match_parent">    <Button        android:id="@+id/send_notice"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="发送通知"/>LinearLayout>

布局activity_result.xml

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_height="match_parent"    android:layout_width="match_parent">    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_centerInParent="true"        android:textSize="24sp"        android:text="结果页"/>RelativeLayout>

MainActivity

package com.example.notificationtest;import androidx.appcompat.app.AppCompatActivity;import androidx.core.app.NotificationCompat;import android.app.Notification;import android.app.NotificationChannel;import android.app.NotificationManager;import android.app.PendingIntent;import android.content.Intent;import android.graphics.BitmapFactory;import android.os.Build;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;public class MainActivity extends AppCompatActivity implements View.OnClickListener {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        Button sendNotice = findViewById(R.id.send_notice);        sendNotice.setOnClickListener(this);    }    @Override    public void onClick(View view) {        final String CHANNEL_ID = "1";        switch (view.getId()) {            case R.id.send_notice:                Log.d("test", "测试");                // 创建通知“意图”                Intent notifyIntent = new Intent(this, ResultActivity.class);                notifyIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK |                        Intent.FLAG_ACTIVITY_CLEAR_TASK);                PendingIntent notifyPendingIntent = PendingIntent.getActivity(this,                        0, notifyIntent, PendingIntent.FLAG_UPDATE_CURRENT);                NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {                    NotificationChannel notificationChannel = new NotificationChannel(CHANNEL_ID,                            "默认通知", NotificationManager.IMPORTANCE_HIGH);                    manager.createNotificationChannel(notificationChannel);                }                Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)                        .setDefaults(Notification.DEFAULT_ALL)                        .setContentTitle("这是内容标题")                        .setContentText("这是正文内容")                        .setWhen(System.currentTimeMillis()) // 指定被通知的时间                        .setSmallIcon(R.mipmap.ic_launcher) // 设置小图标                        .setLargeIcon(BitmapFactory.decodeResource(getResources(), R.mipmap.xiong))                        .setAutoCancel(true) // 设置自动隐藏                        .setPriority(NotificationCompat.PRIORITY_DEFAULT)                        .setContentIntent(notifyPendingIntent) // 设置意图                        .build();                manager.notify(1, notification);                break;            default:               break;        }    }}

ResultActivity

package com.example.notificationtest;import androidx.appcompat.app.AppCompatActivity;import android.os.Bundle;public class ResultActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_result);    }}

参考：
https://developer.android.google.cn/guide/topics/ui/notifiers/notifications