Question

我花了一整天的时间来说明为什么我的自定义通知无法显示。最后，这是约束布局的问题。当我尝试使用约束布局构建custom_notification.xml时，通知不会显示，但是如果我更改为线性布局，则通知工作。有人可以告诉我为什么会这样吗？

具有线性布局的custom_notitication.xml（此布局有效）

 <LinearLayout 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:id="@+id/layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="8dp">
        <Button
            android:id="@+id/button"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            android:text="Button"

        <Button
            android:layout_weight="1"
            android:id="@+id/button2"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            android:text="Button"

            />
    </LinearLayout>

具有约束布局的custom_notitication.xml（此方法无效）

<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:id="@+id/layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="8dp">


    <Button
        android:id="@+id/button"
        android:layout_width="0dp"
        android:layout_weight="1"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:text="Button"
        app:layout_constraintEnd_toStartOf="@+id/button2"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent" />

    <Button
        android:layout_weight="1"
        android:id="@+id/button2"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:text="Button"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/button"
        />
</android.support.constraint.ConstraintLayout>

和kotlin代码

  fun getNotification(context: Context): Notification {
        val mNotificationManager1: NotificationManager?

        val notification: Notification

        mNotificationManager1 = context.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
            createChannel(mNotificationManager1)

        val contentView = RemoteViews(applicationContext.packageName, R.layout.custom_notifaction)

        val mBuilder = NotificationCompat.Builder(applicationContext,"LockScreenTouch")
                .setSmallIcon(R.mipmap.ic_launcher)
                .setCustomBigContentView(contentView)
        notification = mBuilder.build()

        mNotificationManager1.notify(PostNotifactionActivity.ONGOING_NOTIFICATION_ID, notification)
        return notification
    }

    @TargetApi(26)
    @Synchronized
    private fun createChannel(notificationManager: NotificationManager?) {
        val name = "lockScreen"
        val importance = NotificationManager.IMPORTANCE_DEFAULT

        val mChannel = NotificationChannel("LockScreenTouch", name, importance)

        mChannel.enableLights(true)
        mChannel.lightColor = Color.BLUE
        notificationManager!!.createNotificationChannel(mChannel)
    }

和我的buid.gradle

    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.android.support:support-v4:28.0.0'

Answer 1

通知布局使用RemoteViews实现-与小部件相同。

很少有与RemoteView兼容的视图。它只是本机/框架视图的一部分（即不支持视图，没有库视图，没有自定义视图），并且该子集并不详尽：

AdapterViewFlipper
FrameLayout
GridLayout
GridView
LinearLayout
ListView
RelativeLayout
StackView
ViewFlipper
AnalogClock
按钮
天文钟
ImageButton
ImageView
ProgressBar
TextClock
TextView

没有其他视图将起作用。

https://developer.android.com/reference/android/widget/RemoteViews

Android自定义通知不适用于约束布局

1 个答案: