无法解决：firebase-database 15.0.0

Question

我试图将Firebase的实时数据库添加到我的应用程序，一切运行顺利，构建成功，但是我创建的数据库没有添加。这是我的代码：

apply plugin: 'com.android.application'
android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "--"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    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.theartofdev.edmodo:android-image-cropper:2.7.+'
    implementation 'info.hoang8f:fbutton:1.0.5'
    implementation 'com.rengwuxian.materialedittext:library:2.1.4'
    implementation 'com.android.support:cardview-v7:27.0.0'
    implementation 'com.android.support:recyclerview-v7:27.0.0'
    implementation 'com.squareup.picasso:picasso:2.5.2'
    implementation 'com.firebaseui:firebase-ui-database:1.2.0'
    implementation 'com.android.support:design:27.1.0'
    implementation 'com.android.support:support-v4:27.0.0'
    implementation('com.github.bumptech.glide:glide:4.7.1') {
        exclude group: "com.android.support"
    }
    implementation 'com.android.support:support-fragment:27.0.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.7.1'
    implementation('com.github.bumptech.glide:glide:4.7.1@aar') {
        transitive = true
    }
    implementation 'com.google.code.gson:gson:2.8.2'
    implementation 'com.github.bumptech.glide:glide:4.7.1'
    implementation 'com.nostra13.universalimageloader:universal-image-loader:1.9.5'
    implementation 'com.google.firebase:firebase-core:16.0.1'
    implementation 'com.google.firebase:firebase-auth:15.0.0'
    implementation 'com.google.firebase:firebase-database:15.0.0'
    implementation 'com.google.firebase:firebase-storage:15.0.0'
}
apply plugin: 'com.google.gms.google-services'

所有运行都成功，已经同步并连接到Firebase，但是数据没有累加。

有帮助吗？ 谢谢