diff --git a/mobile/build.gradle b/mobile/build.gradle
index 0903681b..289c6dbb 100644
--- a/mobile/build.gradle
+++ b/mobile/build.gradle
@@ -10,7 +10,7 @@ android {
         minSdkVersion 21
         targetSdkVersion 27
         resConfigs "zh-rCN"
-        versionCode 21
+        versionCode 22
         versionName "1.3.1"
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
diff --git a/mobile/src/main/java/be/mygod/vpnhotspot/preference/AlwaysAutoCompleteEditTextPreference.kt b/mobile/src/main/java/be/mygod/vpnhotspot/preference/AlwaysAutoCompleteEditTextPreference.kt
index 12ed4b23..98a2bc1b 100644
--- a/mobile/src/main/java/be/mygod/vpnhotspot/preference/AlwaysAutoCompleteEditTextPreference.kt
+++ b/mobile/src/main/java/be/mygod/vpnhotspot/preference/AlwaysAutoCompleteEditTextPreference.kt
@@ -16,7 +16,7 @@ open class AlwaysAutoCompleteEditTextPreference @JvmOverloads constructor(
         editText.id = android.R.id.edit
     }
 
-    override fun setText(text: String) {
+    override fun setText(text: String?) {
         val oldText = getText()
         super.setText(text)
         if (!TextUtils.equals(text, oldText)) notifyChanged()