From c4395111940f496d5ae404f9e8bf2915c4221796 Mon Sep 17 00:00:00 2001
From: Alessandro Digilio <alessandro.digilio@hotmail.it>
Date: Fri, 30 Oct 2020 01:07:48 +0100
Subject: [PATCH] updated dependencies, fixed app crash when pressing '/'
 operator before numbers

---
 app/build.gradle                                | 17 ++++++++---------
 .../java/com/exuberant/calci/HomeActivity.java  |  4 +++-
 build.gradle                                    |  2 +-
 gradle/wrapper/gradle-wrapper.properties        |  4 ++--
 4 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/app/build.gradle b/app/build.gradle
index c87d2d7..1667529 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,12 +1,11 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 29
-    buildToolsVersion "29.0.2"
+    compileSdkVersion 30
     defaultConfig {
         applicationId "com.exuberant.calci"
         minSdkVersion 21
-        targetSdkVersion 29
+        targetSdkVersion 30
         versionCode 1
         versionName "1.0"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
@@ -21,10 +20,10 @@ android {
 
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
-    implementation 'androidx.appcompat:appcompat:1.1.0'
-    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
-    testImplementation 'junit:junit:4.12'
-    androidTestImplementation 'androidx.test:runner:1.2.0'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
-    implementation 'com.google.android.material:material:1.1.0-beta01'
+    implementation 'androidx.appcompat:appcompat:1.2.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
+    testImplementation 'junit:junit:4.13'
+    androidTestImplementation 'androidx.test:runner:1.3.0'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
+    implementation 'com.google.android.material:material:1.3.0-alpha03'
 }
diff --git a/app/src/main/java/com/exuberant/calci/HomeActivity.java b/app/src/main/java/com/exuberant/calci/HomeActivity.java
index c0f9ac0..c36fc84 100644
--- a/app/src/main/java/com/exuberant/calci/HomeActivity.java
+++ b/app/src/main/java/com/exuberant/calci/HomeActivity.java
@@ -83,7 +83,9 @@ private void handleOperatorClick(String operator){
             totalCalculation += currentNumber + operator;
             currentNumber = "";
         } else {
-            totalCalculation = totalCalculation.substring(0, totalCalculation.length() - 1);
+            if(totalCalculation.length()>0){
+                totalCalculation = totalCalculation.substring(0, totalCalculation.length() - 1);
+            }
             totalCalculation += operator;
         }
     }
diff --git a/build.gradle b/build.gradle
index 05d53ae..874fc1f 100644
--- a/build.gradle
+++ b/build.gradle
@@ -7,7 +7,7 @@ buildscript {
 
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.5.1'
+        classpath 'com.android.tools.build:gradle:4.1.0'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 29a3ec4..5727f5a 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Sun Oct 06 21:16:07 IST 2019
+#Fri Oct 30 01:01:22 CET 2020
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-all.zip