android - firebase_messaging : ^4. 0.0+4 不工作

Question

错误:-

Java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.google.firebase.iid.FirebaseInstanceId.getToken()' on a null object reference

主build.gradle

dependencies { classpath 'com.android.tools.build:gradle:3.3.1' classpath 'com.google.gms:google-services:4.0.1' }

应用级build.gradle

dependencies { testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' implementation 'com.google.firebase:firebase-core:16.0.1' } apply plugin: 'com.google.gms.google-services'

Android.manifest.xml

<activity android:name=".MainActivity" android:launchMode="singleTop" android:theme="@style/LaunchTheme" android:largeHeap="true" android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode" android:hardwareAccelerated="true" android:windowSoftInputMode="adjustResize">
    <!-- This keeps the window background of the activity showing
    until Flutter renders its first frame. It can be removed if
    there is no splash screen (such as the default splash screen
    defined in @style/LaunchTheme). -->
    <meta-data android:name="io.flutter.app.android.SplashScreenUntilFirstFrame" android:value="true" />

    <intent-filter>
        <action android:name="android.intent.action.MAIN"/>
        <category android:name="android.intent.category.LAUNCHER"/>
    </intent-filter>

</activity>

Answer 1

我发现的主要问题是位置插件和 FCM 插件所需的谷歌服务版本不同。

在最底部的app级build.gradle文件

 dependencies {
        testImplementation 'junit:junit:4.12'
        androidTestImplementation 'com.android.support.test:runner:1.0.2'
        androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
        implementation 'com.google.firebase:firebase-core:16.0.1' } 
apply plugin: 'com.google.gms.google-services' com.google.gms.googleservices.GoogleServicesPlugin.config.disableVersionCheck
    = true