diff --git a/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/Server2Activity.kt b/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/Server2Activity.kt
index a021c1ec..137840b4 100644
--- a/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/Server2Activity.kt
+++ b/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/Server2Activity.kt
@@ -4,6 +4,7 @@ import android.os.Bundle
 import android.support.v7.app.AlertDialog
 import android.text.Editable
 import android.text.TextUtils
+import android.util.Log
 import android.view.Menu
 import android.view.MenuItem
 import com.google.gson.Gson
@@ -100,6 +101,11 @@ class Server2Activity : BaseActivity() {
         if (saveSuccess) {
             //update config
             defaultDPreference.setPrefString(AppConfig.ANG_CONFIG + edit_guid, tv_content.text.toString())
+            if (edit_index == configs.index) {
+                if (!AngConfigManager.genStoreV2rayConfig(edit_index)) {
+                    Log.d(AppConfig.ANG_PACKAGE, "update custom config $edit_index but generate full configuration failed!")
+                }
+            }
             finish()
             return true
         } else {
diff --git a/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/SettingsActivity.kt b/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/SettingsActivity.kt
index 6ab91599..6bdadcc6 100644
--- a/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/SettingsActivity.kt
+++ b/V2rayNG/app/src/main/kotlin/com/v2ray/ang/ui/SettingsActivity.kt
@@ -1,5 +1,6 @@
 package com.v2ray.ang.ui
 
+import android.arch.lifecycle.ViewModelProviders
 import android.content.Intent
 import android.os.Bundle
 import android.support.v7.preference.*
@@ -9,6 +10,7 @@ import com.v2ray.ang.AppConfig
 import com.v2ray.ang.extension.toast
 import com.v2ray.ang.util.AngConfigManager
 import com.v2ray.ang.util.Utils
+import com.v2ray.ang.viewmodel.SettingsViewModel
 
 class SettingsActivity : BaseActivity() {
     companion object {
@@ -37,6 +39,8 @@ class SettingsActivity : BaseActivity() {
         const val PREF_FORWARD_IPV6 = "pref_forward_ipv6"
     }
 
+    private val settingsViewModel by lazy { ViewModelProviders.of(this).get(SettingsViewModel::class.java) }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_settings)
@@ -44,6 +48,8 @@ class SettingsActivity : BaseActivity() {
         title = getString(R.string.title_settings)
 
         supportActionBar?.setDisplayHomeAsUpEnabled(true)
+
+        settingsViewModel.startListenPreferenceChange()
     }
 
     class SettingsFragment : PreferenceFragmentCompat() {
diff --git a/V2rayNG/app/src/main/kotlin/com/v2ray/ang/viewmodel/SettingsViewModel.kt b/V2rayNG/app/src/main/kotlin/com/v2ray/ang/viewmodel/SettingsViewModel.kt
new file mode 100644
index 00000000..5f278a60
--- /dev/null
+++ b/V2rayNG/app/src/main/kotlin/com/v2ray/ang/viewmodel/SettingsViewModel.kt
@@ -0,0 +1,46 @@
+package com.v2ray.ang.viewmodel
+
+import android.app.Application
+import android.arch.lifecycle.AndroidViewModel
+import android.content.SharedPreferences
+import android.support.v7.preference.PreferenceManager
+import android.util.Log
+import com.v2ray.ang.AppConfig
+import com.v2ray.ang.ui.SettingsActivity.Companion
+import com.v2ray.ang.util.AngConfigManager
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.launch
+
+class SettingsViewModel(application: Application) : AndroidViewModel(application), SharedPreferences.OnSharedPreferenceChangeListener {
+    fun startListenPreferenceChange() {
+        PreferenceManager.getDefaultSharedPreferences(getApplication()).registerOnSharedPreferenceChangeListener(this)
+    }
+
+    override fun onCleared() {
+        PreferenceManager.getDefaultSharedPreferences(getApplication()).unregisterOnSharedPreferenceChangeListener(this)
+        Log.i(AppConfig.ANG_PACKAGE, "Settings ViewModel is cleared")
+        super.onCleared()
+    }
+
+    override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences, key: String?) {
+        Log.d(AppConfig.ANG_PACKAGE, "Observe settings changed: $key")
+        when(key) {
+            Companion.PREF_SNIFFING_ENABLED,
+            Companion.PREF_PROXY_SHARING,
+            Companion.PREF_LOCAL_DNS_ENABLED,
+            Companion.PREF_REMOTE_DNS,
+            Companion.PREF_DOMESTIC_DNS,
+            Companion.PREF_ROUTING_DOMAIN_STRATEGY,
+            Companion.PREF_ROUTING_MODE,
+            AppConfig.PREF_V2RAY_ROUTING_AGENT,
+            AppConfig.PREF_V2RAY_ROUTING_BLOCKED,
+            AppConfig.PREF_V2RAY_ROUTING_DIRECT -> {
+                GlobalScope.launch {
+                    if (!AngConfigManager.genStoreV2rayConfig(AngConfigManager.configs.index)) {
+                        Log.d(AppConfig.ANG_PACKAGE, "$key changed but generate full configuration failed!")
+                    }
+                }
+            }
+        }
+    }
+}