fix missing class exception

android/app/build.gradle

@@ -84,13 +84,13 @@ def enableSeparateBuildPerCPUArchitecture = true
 def enableProguardInReleaseBuilds = false
 
 android {
-    compileSdkVersion 27
-    buildToolsVersion '27.0.0'
+    compileSdkVersion rootProject.ext.compileSdkVersion
+    buildToolsVersion rootProject.ext.buildToolsVersion
 
     defaultConfig {
         applicationId "com.aretherecookies"
-        minSdkVersion 16
-        targetSdkVersion 27
+        minSdkVersion rootProject.ext.minSdkVersion
+        targetSdkVersion rootProject.ext.targetSdkVersion
         versionCode 50
         versionName "1.0"
         ndk {
@@ -146,9 +146,10 @@ dependencies {
     compile project(':react-native-maps')
     compile project(':react-native-vector-icons')
     compile project(':react-native-image-picker')
-    compile fileTree(include: ['*.jar'], dir: 'libs')
-    compile 'com.facebook.react:react-native:+'
-    // From node_modules
+
+    implementation fileTree(dir: "libs", include: ["*.jar"])
+    implementation "com.android.support:appcompat-v7:${rootProject.ext.supportLibVersion}"
+    implementation "com.facebook.react:react-native:+"  // From node_modules
 }
 
 // Run this once to be able to run the application with BUCK

android/build.gradle

@@ -3,7 +3,8 @@
 buildscript {
 		ext {
 			compileSdkVersion   = 27
-			targetSdkVersion    = 27
+			minSdkVersion				= 16
+			targetSdkVersion    = 26
 			buildToolsVersion   = "27.0.3"
 			supportLibVersion   = "27.1.1"
 			googlePlayServicesVersion = "15.0.1"