[ion/sdl] Clean the Android app structure

ion/src/sdl/android/build.gradle

@@ -0,0 +1,55 @@
+buildscript {
+  repositories {
+    jcenter()
+    google()
+  }
+  dependencies {
+    classpath 'com.android.tools.build:gradle:3.2.0'
+    // NOTE: Do not place your application dependencies here; they belong
+    // in the individual module build.gradle files
+  }
+}
+
+allprojects {
+  repositories {
+    jcenter()
+    google()
+  }
+}
+
+apply plugin: 'com.android.application'
+
+android {
+  compileSdkVersion 28
+  defaultConfig {
+    applicationId "com.numworks.calculator"
+    minSdkVersion 16
+    targetSdkVersion 26
+    versionCode 1
+    versionName "1.0"
+  }
+  buildTypes {
+    release {
+      minifyEnabled false
+      proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+    }
+  }
+  sourceSets{
+    main {
+      manifest.srcFile 'src/AndroidManifest.xml'
+      res.srcDir 'src/res'
+      java.srcDir 'src'
+      jniLibs.srcDir 'libs'
+      assets.srcDir '../../../assets'
+    }
+  }
+
+  lintOptions {
+    abortOnError false
+  }
+}
+
+dependencies {
+  implementation fileTree(include: ['*.jar'], dir: 'libs')
+  implementation "androidx.appcompat:appcompat:1.0.0"
+}

ion/src/sdl/android/proguard-rules.pro

@@ -0,0 +1,17 @@
+# Add project specific ProGuard rules here.
+# By default, the flags in this file are appended to flags specified
+# in [sdk]/tools/proguard/proguard-android.txt
+# You can edit the include path and order by changing the proguardFiles
+# directive in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# Add any project specific keep options here:
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}