cannot find symbol class NotificationManagerCompat

问题

I am trying to build a notification method that would result in a notification appearing on the locked screen when a particular beacon is detected. My understanding is that I need to include .setVisibility(0) in the following code:

public void showNotification(Beacon beacon) {

    Resources r = getResources();
    int random = (int)System.currentTimeMillis();
    Notification notification = new NotificationCompat.Builder(this)
            .setSmallIcon(android.R.drawable.ic_popup_reminder)
            .setContentTitle("Beacons Found")
            .setContentText(beacon.getID().toString())
            .setVisibility(0)  // allow notification to appear on locked screen
            .setAutoCancel(true)
            .build();

    NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
    notificationManager.notify(random, notification);

}

I have the above code, but when I run it it says "cannot find symbol variable SetVisibility". I have done some research online and it seems I need to import this:

 import android.support.v4.app.NotificationManagerCompat;

But if I include this import statement, it would say "cannot find symbol class NotificationManagerCompat"

What should I do? I have already installed Android Support Repository SDK and have the "android-support-v4.jar in the libs folder of the project

回答1:

Maybe you have this error come up, because you added a new module to your project.

To fix it, change minSdkVersion, targetSdkVersion, buildToolsVersion, and compileSdkVersion to match the build.gradle in your original module.

After that set minifyEnabled to false.

What it actually fixed it for me (while using Android Studio 3.0.1) was setting facebook to

compile 'com.facebook.android:facebook-android-sdk:4.26.0'

Also check your other libs and dependencies and your build file.

My current build file:

allprojects {
    repositories {
        jcenter()
        maven  {
            url "http://repo1.maven.org/maven2"
        }
        // maven  {
        //    url 'https://maven.google.com'
        // }
        // since Android Studio 3.0.0
        // or google()
        flatDir {
            dirs 'libs'
        }
    }
}

来源：https://stackoverflow.com/questions/43259902/cannot-find-symbol-class-notificationmanagercompat