--- a/build.gradle
+++ b/build.gradle
@@ -1,3 +1,19 @@
+buildscript {
+    repositories {
+        google()
+        jcenter()
+    }
+
+    dependencies {
+        classpath 'com.android.tools.build:gradle:3.4.2'
+    }
+}
+
+repositories {
+    google()
+    jcenter()
+}
+
 apply plugin: 'com.android.application'

 android {
@@ -43,6 +59,8 @@
 dependencies {
     implementation fileTree(include: ['*.jar'], dir: 'libs')

+    implementation 'net.lingala.zip4j:zip4j:1.3.3'
+
     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'