Bug fix

https://github.com/2dust/v2rayNG/issues/4723

V2rayNG/app/src/main/java/com/v2ray/ang/service/V2RayVpnService.kt

@@ -194,25 +194,7 @@ class V2RayVpnService : VpnService(), ServiceControl {
 
         builder.setSession(V2RayServiceManager.getRunningServerName())
 
-        val selfPackageName = BuildConfig.APPLICATION_ID
+        configurePerAppProxy(builder)
-        if (MmkvManager.decodeSettingsBool(AppConfig.PREF_PER_APP_PROXY)) {
-            val apps = MmkvManager.decodeSettingsStringSet(AppConfig.PREF_PER_APP_PROXY_SET)
-            val bypassApps = MmkvManager.decodeSettingsBool(AppConfig.PREF_BYPASS_APPS)
-            //process self package
-            if (bypassApps) apps?.add(selfPackageName) else apps?.remove(selfPackageName)
-            apps?.forEach {
-                try {
-                    if (bypassApps)
-                        builder.addDisallowedApplication(it)
-                    else
-                        builder.addAllowedApplication(it)
-                } catch (e: PackageManager.NameNotFoundException) {
-                    Log.e(AppConfig.TAG, "Failed to configure app in VPN: ${e.localizedMessage}", e)
-                }
-            }
-        } else {
-            builder.addDisallowedApplication(selfPackageName)
-        }
 
         // Close the old interface since the parameters have been changed.
         try {
@@ -249,6 +231,51 @@ class V2RayVpnService : VpnService(), ServiceControl {
         return false
     }
 
+    /**
+     * Configures per-app proxy rules for the VPN builder.
+     *
+     * - If per-app proxy is not enabled, disallow the VPN service's own package.
+     * - If no apps are selected, disallow the VPN service's own package.
+     * - If bypass mode is enabled, disallow all selected apps (including self).
+     * - If proxy mode is enabled, only allow the selected apps (excluding self).
+     *
+     * @param builder The VPN Builder to configure.
+     */
+    private fun configurePerAppProxy(builder: Builder) {
+        val selfPackageName = BuildConfig.APPLICATION_ID
+
+        // If per-app proxy is not enabled, disallow the VPN service's own package and return
+        if (MmkvManager.decodeSettingsBool(AppConfig.PREF_PER_APP_PROXY) == false) {
+            builder.addDisallowedApplication(selfPackageName)
+            return
+        }
+
+        // If no apps are selected, disallow the VPN service's own package and return
+        val apps = MmkvManager.decodeSettingsStringSet(AppConfig.PREF_PER_APP_PROXY_SET)
+        if (apps.isNullOrEmpty()) {
+            builder.addDisallowedApplication(selfPackageName)
+            return
+        }
+
+        val bypassApps = MmkvManager.decodeSettingsBool(AppConfig.PREF_BYPASS_APPS)
+        // Handle the VPN service's own package according to the mode
+        if (bypassApps) apps.add(selfPackageName) else apps.remove(selfPackageName)
+
+        apps.forEach {
+            try {
+                if (bypassApps) {
+                    // In bypass mode, disallow the selected apps
+                    builder.addDisallowedApplication(it)
+                } else {
+                    // In proxy mode, only allow the selected apps
+                    builder.addAllowedApplication(it)
+                }
+            } catch (e: PackageManager.NameNotFoundException) {
+                Log.e(AppConfig.TAG, "Failed to configure app in VPN: ${e.localizedMessage}", e)
+            }
+        }
+    }
+
     /**
      * Runs the tun2socks process.
      * Starts the tun2socks process with the appropriate parameters.