diff --git a/app/build.gradle b/app/build.gradle
index c21a2091..e0cd8e73 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -32,13 +32,13 @@ android {
 }
 
 dependencies {
-    compile 'com.simplemobiletools:commons:2.17.2'
+    compile 'com.simplemobiletools:commons:2.20.1'
     compile 'com.bignerdranch.android:recyclerview-multiselect:0.2'
     compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
 }
 
 buildscript {
-    ext.kotlin_version = '1.1.1'
+    ext.kotlin_version = '1.1.2-5'
     repositories {
         mavenCentral()
     }
diff --git a/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/ChangeSortingDialog.kt b/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/ChangeSortingDialog.kt
index 4786fb92..7b43c825 100644
--- a/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/ChangeSortingDialog.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/ChangeSortingDialog.kt
@@ -81,6 +81,6 @@ class ChangeSortingDialog(val activity: SimpleActivity, val path: String = "", v
             config.removeFolderSorting(path)
             config.sorting = sorting
         }
-        callback.invoke()
+        callback()
     }
 }
diff --git a/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/CreateNewItemDialog.kt b/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/CreateNewItemDialog.kt
index f37d6dbf..ef5771f5 100644
--- a/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/CreateNewItemDialog.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/filemanager/dialogs/CreateNewItemDialog.kt
@@ -23,11 +23,11 @@ class CreateNewItemDialog(val activity: Activity, val path: String, val callback
             getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(View.OnClickListener {
                 val name = view.item_name.value
                 if (name.isEmpty()) {
-                    context.toast(R.string.empty_name)
+                    activity.toast(R.string.empty_name)
                 } else if (name.isAValidFilename()) {
                     val file = File(path, name)
                     if (file.exists()) {
-                        context.toast(R.string.name_taken)
+                        activity.toast(R.string.name_taken)
                         return@OnClickListener
                     }
 
@@ -41,7 +41,7 @@ class CreateNewItemDialog(val activity: Activity, val path: String, val callback
                         }
                     }
                 } else {
-                    context.toast(R.string.invalid_name)
+                    activity.toast(R.string.invalid_name)
                 }
             })
         }
@@ -84,6 +84,6 @@ class CreateNewItemDialog(val activity: Activity, val path: String, val callback
 
     private fun success(alertDialog: AlertDialog) {
         alertDialog.dismiss()
-        callback.invoke()
+        callback()
     }
 }
diff --git a/app/src/main/kotlin/com/simplemobiletools/filemanager/fragments/ItemsFragment.kt b/app/src/main/kotlin/com/simplemobiletools/filemanager/fragments/ItemsFragment.kt
index 1cf79d5e..2d5c6153 100644
--- a/app/src/main/kotlin/com/simplemobiletools/filemanager/fragments/ItemsFragment.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/filemanager/fragments/ItemsFragment.kt
@@ -171,7 +171,7 @@ class ItemsFragment : android.support.v4.app.Fragment(), ItemsAdapter.ItemOperat
                     startActivity(this)
                 } catch (e: ActivityNotFoundException) {
                     if (!tryGenericMimeType(this, mimeType!!, file)) {
-                        context.toast(R.string.no_app_found)
+                        activity.toast(R.string.no_app_found)
                     }
                 }
             }
diff --git a/build.gradle b/build.gradle
index d0aa7043..c2eea8e2 100644
--- a/build.gradle
+++ b/build.gradle
@@ -5,7 +5,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.3.2'
+        classpath 'com.android.tools.build:gradle:2.3.3'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files