diff --git a/src/AndroidApp/android_remocons/build.gradle b/src/AndroidApp/android_remocons/build.gradle
index 29b6eef..745faba 100644
--- a/src/AndroidApp/android_remocons/build.gradle
+++ b/src/AndroidApp/android_remocons/build.gradle
@@ -32,6 +32,8 @@ buildscript {
         mavenCentral()
         maven{ url'http://maven.aliyun.com/nexus/content/groups/public/' }
         maven{ url'http://maven.aliyun.com/nexus/content/repositories/jcenter'}
+        ///maven{ url'https://maven.aliyun.com/repository/public'}
+
     }
 
 }
diff --git a/src/AndroidApp/android_remocons/common_tools/src/main/java/com/github/rosjava/android_remocons/common_tools/rocon/AppLauncher.java b/src/AndroidApp/android_remocons/common_tools/src/main/java/com/github/rosjava/android_remocons/common_tools/rocon/AppLauncher.java
index c964cc9..713161e 100644
--- a/src/AndroidApp/android_remocons/common_tools/src/main/java/com/github/rosjava/android_remocons/common_tools/rocon/AppLauncher.java
+++ b/src/AndroidApp/android_remocons/common_tools/src/main/java/com/github/rosjava/android_remocons/common_tools/rocon/AppLauncher.java
@@ -124,7 +124,7 @@ public class AppLauncher {
     static public AppType checkAppType(String app_name){
         String web_url_desc = "web_url(";
         String web_app_desc = "web_app(";
-        if (Patterns.WEB_URL.matcher(app_name).matches() == true) {
+        if (Patterns.WEB_URL.matcher(app_name).matches()) {
             return AppType.URL;
         }
         else if(app_name.length() == 0){
@@ -263,7 +263,7 @@ public class AppLauncher {
      */
     static private Result launchUrl (final Activity parent, final RoconDescription concert,
                                        final rocon_interaction_msgs.Interaction app) {
-        try
+        try //rocon app的bug在这个方法中
         {
             // Validate the URL before starting anything
             String app_name = "";
@@ -305,8 +305,8 @@ public class AppLauncher {
             return Result.SUCCESS;
         }
         catch (MalformedURLException e)
-        {
-            return Result.MALFORMED_URI.withMsg("App URL is not valid. " + e.getMessage());
+        {//rocon app的no protocol bug
+            return Result.MALFORMED_URI.withMsg("App URL is not valid. " + e.getMessage()  + " It's in launchUrl.");
         }
         catch (ActivityNotFoundException e) {
             // This cannot happen for a web site, right? must mean that I have no web browser!
@@ -368,7 +368,7 @@ public class AppLauncher {
         }
         catch (MalformedURLException e)
         {
-            return Result.MALFORMED_URI.withMsg("App URL is not valid. " + e.getMessage());
+            return Result.MALFORMED_URI.withMsg("App URL is not valid. " + e.getMessage() + " It's in launchWebUrl.");
         }
         catch (ActivityNotFoundException e) {
             // This cannot happen for a web site, right? must mean that I have no web browser!
@@ -476,7 +476,7 @@ public class AppLauncher {
         }
         catch (MalformedURLException e)
         {
-            return Result.MALFORMED_URI.withMsg("App URL is not valid. " + e.getMessage());
+            return Result.MALFORMED_URI.withMsg("App URL is not valid. " + e.getMessage() + " It's in launchWebApp.");
         }
         catch (ActivityNotFoundException e) {
             // This cannot happen for a web site, right? must mean that I have no web browser!
diff --git a/src/AndroidApp/android_remocons/rocon_remocon/src/main/java/com/github/rosjava/android_remocons/rocon_remocon/Remocon.java b/src/AndroidApp/android_remocons/rocon_remocon/src/main/java/com/github/rosjava/android_remocons/rocon_remocon/Remocon.java
index 8b173a1..e8114e8 100644
--- a/src/AndroidApp/android_remocons/rocon_remocon/src/main/java/com/github/rosjava/android_remocons/rocon_remocon/Remocon.java
+++ b/src/AndroidApp/android_remocons/rocon_remocon/src/main/java/com/github/rosjava/android_remocons/rocon_remocon/Remocon.java
@@ -299,7 +299,7 @@ public class Remocon extends RosActivity {
                             else {
                                 AlertDialog.Builder dialog = new AlertDialog.Builder(Remocon.this);
                                 dialog.setIcon(R.drawable.failure_small);
-                                dialog.setTitle("Cannot start app");
+                                dialog.setTitle("Cannot start app: " + result.toString());//加上result的具体结果，便于调试错误 by lcp
                                 dialog.setMessage(result.message);
                                 dialog.setPositiveButton("Accept", new DialogInterface.OnClickListener() {
                                     @Override