Move version definitions to gradle.properties

- Update minSdkVersion to 18

android/app/build.gradle

@@ -146,7 +146,7 @@ def getEnvOrConfig = { varName ->
 }
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion rootProject.ext.compileSdkVersion
 
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8
@@ -155,8 +155,8 @@ android {
 
     defaultConfig {
         applicationId "im.status.ethereum"
-        minSdkVersion 23
+        minSdkVersion rootProject.ext.minSdkVersion
-        targetSdkVersion 28
+        targetSdkVersion rootProject.ext.targetSdkVersion
         multiDexEnabled true
         versionCode getVersionCode()
         versionName getVersionName()
@@ -268,7 +268,7 @@ dependencies {
     implementation project(':react-native-dialogs')
     implementation project(':realm')
     implementation fileTree(dir: "libs", include: ["*.jar"])
-    implementation "com.android.support:appcompat-v7:28.0.0"
+    implementation "com.android.support:appcompat-v7:${rootProject.ext.supportLibVersion}"
     // Force using exact RN version instead of relying on gradle dependency resolution
     // https://docs.gradle.org/current/userguide/introduction_dependency_management.html#sec:dependency_resolution
     //compile ("com.facebook.react:react-native:0.55.4") { force = true }  // From node_modules

android/build.gradle

@@ -1,21 +1,25 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
+/**
+* Project-wide gradle configuration properties for use by all modules
+*/
+ext {
+    buildToolsVersion   = project.buildToolsVersion
+    minSdkVersion       = Integer.valueOf(project.minSdkVersion)
+    compileSdkVersion   = Integer.valueOf(project.compileSdkVersion)
+    targetSdkVersion    = Integer.valueOf(project.targetSdkVersion)
+    supportLibVersion   = project.supportLibVersion
+    gradleBuildTools    = project.gradleBuildTools
+}
+
 buildscript {
-    ext {
-        buildToolsVersion = "28.0.3"
-        minSdkVersion = 16
-        compileSdkVersion = 28
-        targetSdkVersion = 28
-        supportLibVersion = "28.0.0"
-        gradleBuildTools = 'com.android.tools.build:gradle:3.4.1'
-    }
     repositories {
         flatDir { dirs "libs", "${rootDir}/app/libs" }
         google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.4.1'
+        classpath project.ext.gradleBuildTools
         // google-services downgraded from 4.1.0 because of
         // https://github.com/invertase/react-native-firebase/issues/766#issuecomment-365116012
         classpath 'com.google.gms:google-services:4.0.1'
@@ -30,11 +34,11 @@ subprojects {
     afterEvaluate {
         if (project.hasProperty("android")) {
             android {
-                compileSdkVersion 28
+                compileSdkVersion rootProject.ext.compileSdkVersion
-                buildToolsVersion "28.0.3"
+                buildToolsVersion rootProject.ext.buildToolsVersion
 
                 defaultConfig {
-                    targetSdkVersion 28
+                    targetSdkVersion rootProject.ext.targetSdkVersion
                 }
             }
         }

android/gradle.properties

@@ -19,6 +19,15 @@
 
 # To create a new keystore for development purposes (https://developer.android.com/studio/publish/app-signing.html)
 # $keytool -genkey -v -keystore ./status-keystore.jks -keyalg RSA -keysize 2048 -validity 10000 -alias status
+
+# Version requirements used throughout the Gradle scripts
+minSdkVersion=18
+compileSdkVersion=28
+targetSdkVersion=28
+buildToolsVersion=28.0.3
+supportLibVersion=28.0.0
+gradleBuildTools=com.android.tools.build:gradle:3.4.1
+
 STATUS_RELEASE_STORE_FILE=~/.gradle/status-im.keystore
 STATUS_RELEASE_STORE_PASSWORD=password
 STATUS_RELEASE_KEY_ALIAS=status

modules/react-native-status/android/build.gradle

@@ -11,11 +11,11 @@ def getStatusGoSHA1 = { ->
 }
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion rootProject.ext.compileSdkVersion
 
     defaultConfig {
-        minSdkVersion 23
+        minSdkVersion rootProject.ext.minSdkVersion
-        targetSdkVersion 28
+        targetSdkVersion rootProject.ext.targetSdkVersion
         versionCode 1
         versionName "1.0"
     }

nix/status-go/default.nix

@@ -31,7 +31,7 @@ let
         "ANDROID_NDK_HOME=${androidPkgs.ndk-bundle}/libexec/android-sdk/ndk-bundle"
         "PATH=${makeBinPath [ openjdk ]}:$PATH"
       ];
-      gomobileExtraFlags = [ "-androidapi 21" ];
+      gomobileExtraFlags = [ "-androidapi 18" ];
     };
     ios = {
       name = "ios";