Kotlin Android通知

本文概述

• 设置Android通知属性
• Android通知示例

Android Notification提供了有关应用程序中发生的操作的简短及时信息, 即使该应用程序未运行也是如此。该通知将显示图标, 标题和一些内容文本。

设置Android通知属性

使用NotificationCompat.Builder对象设置Android通知的属性。下面提到了一些通知属性：

• setSmallIcon()：设置通知图标。
• setContentTitle()：用于设置通知标题。
• setContentText()：用于设置文本消息。
• setAutoCancel()：设置通知的cancelable属性。
• setPriority()：设置通知的优先级。

Android通知示例

在此示例中, 我们将创建一条通知消息, 然后单击它会启动另一个活动。

activity_main.xml

在activity_main.xml文件中添加以下代码。

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="example.srcmini02.com.androidnotification.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="ANDROID NOTIFICATION"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.091"
        android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/button"
        android:layout_marginBottom="112dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:text="Notify"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

</android.support.constraint.ConstraintLayout>

创建一个名为activity_notification_view.xml的活动, 并添加以下代码。该活动将在单击通知时启动。 TextView用于显示通知消息。

activity_notification_view.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="example.srcmini02.com.androidnotification.NotificationView">

    <TextView
        android:id="@+id/textView2"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:text="your detail of notification..."
        android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.096"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView2"
        app:layout_constraintVertical_bias="0.206"
        android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium"/>

</android.support.constraint.ConstraintLayout>

MainActivity.java

在MainActivity.java类中添加以下代码。在此类中, 单击按钮将调用addNotification()方法, 在此方法中我们实现NotificationCompat.Builder对象以设置通知属性。 NotificationManager.notify()方法用于显示通知。 Intent类用于在拍打通知时调用另一个活动（NotificationView.java）。

package example.srcmini02.com.androidnotification;

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

public class MainActivity extends AppCompatActivity {
    Button button;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button = findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                addNotification();
            }
        });
    }

    private void addNotification() {
        NotificationCompat.Builder builder =
                new NotificationCompat.Builder(this)
                        .setSmallIcon(R.drawable.messageicon) //set icon for notification
                        .setContentTitle("Notifications Example") //set title of notification
                        .setContentText("This is a notification message")//this is notification message
                        .setAutoCancel(true) // makes auto cancel of notification
                        .setPriority(NotificationCompat.PRIORITY_DEFAULT); //set priority of notification


        Intent notificationIntent = new Intent(this, NotificationView.class);
        notificationIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        //notification message will get at NotificationView
        notificationIntent.putExtra("message", "This is a notification message");

        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT);
        builder.setContentIntent(pendingIntent);

        // Add as notification
        NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        manager.notify(0, builder.build());
    }
}

NotificationView.java

NotificationView.java类接收通知消息, 并显示在TextView中。点按通知时将调用此类。

package example.srcmini02.com.androidnotification;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

public class NotificationView extends AppCompatActivity {
    TextView textView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_notification_view);
        textView = findViewById(R.id.textView);
        //getting the notification message
        String message=getIntent().getStringExtra("message");
        textView.setText(message);
    }
}

strings.xml

<resources>
    <string name="app_name">AndroidNotification</string>
    <string name="notification_activity">NotificationView</string>
</resources>

AndroidManifest.xml

在AndroidManifest.xml文件中添加以下代码。

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="example.srcmini02.com.androidnotification">

    <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=".NotificationView"
            android:label="@string/notification_activity"
            android:parentActivityName=".MainActivity">
            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value=".MainActivity"/>
        </activity>
    </application>

</manifest>

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