update commons to 3.0.23 with minor improvements

app/build.gradle

@@ -20,14 +20,10 @@ android {
     }
 
     buildTypes {
-        debug {
-            buildConfigField "boolean", "USE_LEAK_CANARY", "true"
-        }
         release {
             minifyEnabled true
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
             signingConfig signingConfigs.release
-            buildConfigField "boolean", "USE_LEAK_CANARY", "false"
         }
     }
 
@@ -46,7 +42,7 @@ ext {
 }
 
 dependencies {
-    implementation 'com.simplemobiletools:commons:3.0.21'
+    implementation 'com.simplemobiletools:commons:3.0.23'
 
     debugImplementation "com.squareup.leakcanary:leakcanary-android:$leakCanaryVersion"
     releaseImplementation "com.squareup.leakcanary:leakcanary-android-no-op:$leakCanaryVersion"

app/src/main/kotlin/com/simplemobiletools/draw/App.kt

@@ -2,13 +2,12 @@ package com.simplemobiletools.draw
 
 import android.app.Application
 import com.simplemobiletools.commons.extensions.checkUseEnglish
-import com.simplemobiletools.draw.BuildConfig.USE_LEAK_CANARY
 import com.squareup.leakcanary.LeakCanary
 
 class App : Application() {
     override fun onCreate() {
         super.onCreate()
-        if (USE_LEAK_CANARY) {
+        if (BuildConfig.DEBUG) {
             if (LeakCanary.isInAnalyzerProcess(this)) {
                 return
             }

app/src/main/kotlin/com/simplemobiletools/draw/activities/MainActivity.kt

@@ -88,6 +88,11 @@ class MainActivity : SimpleActivity(), CanvasListener {
         storeStateVariables()
     }
 
+    override fun onDestroy() {
+        super.onDestroy()
+        my_canvas.mListener = null
+    }
+
     override fun onCreateOptionsMenu(menu: Menu): Boolean {
         menuInflater.inflate(R.menu.menu, menu)
         menu.apply {