Fix the vpnsetting NPE crash.

The bug is triggered by rotating the screen after restoring the
vpn setting which was showing the connect dialog from the recent tasks.

Change-Id: I2562b208fa28f9b6ffa8acba1ab14e0f83b3a0c6

src/com/android/settings/vpn/VpnEditor.java

@@ -28,6 +28,7 @@ import android.net.vpn.L2tpIpsecProfile;
 import android.net.vpn.L2tpIpsecPskProfile;
 import android.net.vpn.L2tpProfile;
 import android.net.vpn.PptpProfile;
+import android.net.vpn.VpnManager;
 import android.net.vpn.VpnProfile;
 import android.os.Bundle;
 import android.os.Parcel;
@@ -37,6 +38,7 @@ import android.text.TextUtils;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
+import android.widget.Toast;
 
 /**
  * The activity class for editing a new or existing VPN profile.
@@ -48,6 +50,7 @@ public class VpnEditor extends SettingsPreferenceFragment {
     private static final String KEY_PROFILE = "profile";
     private static final String KEY_ORIGINAL_PROFILE_NAME = "orig_profile_name";
 
+    private VpnManager mVpnManager;
     private VpnProfileEditor mProfileEditor;
     private boolean mAddingProfile;
     private byte[] mOriginalProfileData;
@@ -63,6 +66,7 @@ public class VpnEditor extends SettingsPreferenceFragment {
     @Override
     public void onActivityCreated(Bundle savedInstanceState) {
         super.onActivityCreated(savedInstanceState);
+        mVpnManager = new VpnManager(getActivity());
 
         VpnProfile p;
         if (savedInstanceState != null) {
@@ -111,8 +115,15 @@ public class VpnEditor extends SettingsPreferenceFragment {
             case MENU_SAVE:
                 Intent resultIntent = validateAndGetResult();
                 if (resultIntent != null) {
-                    ((PreferenceActivity) getActivity()).finishPreferencePanel(
-                            this, Activity.RESULT_OK, resultIntent);
+                    PreferenceActivity activity =
+                            (PreferenceActivity) getActivity();
+                    if (!mVpnManager.isIdle()) {
+                        Toast.makeText(activity, R.string.service_busy,
+                                Toast.LENGTH_SHORT).show();
+                    } else {
+                        activity.finishPreferencePanel(this,
+                                Activity.RESULT_OK, resultIntent);
+                    }
                 }
                 return true;
 

src/com/android/settings/vpn/VpnSettings.java

@@ -131,7 +131,7 @@ public class VpnSettings extends SettingsPreferenceFragment
 
     private int mConnectingErrorCode = NO_ERROR;
 
-    private Dialog mShowingDialog;
+    private Dialog mShowingDialog, mConnectDialog;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
@@ -182,7 +182,6 @@ public class VpnSettings extends SettingsPreferenceFragment
         // for long-press gesture on a profile preference
         registerForContextMenu(getListView());
 
-
         retrieveVpnListFromStorage();
         restoreInstanceState(savedInstanceState);
     }
@@ -208,7 +207,13 @@ public class VpnSettings extends SettingsPreferenceFragment
             mUnlockAction = null;
             getActivity().runOnUiThread(action);
         }
-        checkVpnConnectionStatus();
+        if (mConnectDialog == null || !mConnectDialog.isShowing()) {
+            checkVpnConnectionStatus();
+        } else {
+            // Dismiss the connect dialog in case there is another instance
+            // trying to operate a vpn connection.
+            if (!mVpnManager.isIdle()) removeConnectDialog();
+        }
     }
 
     @Override
@@ -237,7 +242,8 @@ public class VpnSettings extends SettingsPreferenceFragment
     public Dialog onCreateDialog (int id) {
         switch (id) {
             case DIALOG_CONNECT:
-                return createConnectDialog();
+                mConnectDialog = createConnectDialog();
+                return mConnectDialog;
 
             case DIALOG_SECRET_NOT_SET:
                 return createSecretNotSetDialog();
@@ -253,11 +259,19 @@ public class VpnSettings extends SettingsPreferenceFragment
         }
     }
 
+    private void removeConnectDialog() {
+        if (mConnectDialog != null) {
+            mConnectDialog.dismiss();
+            mConnectDialog = null;
+            checkVpnConnectionStatus();
+        }
+    }
+
     private class ConnectDialog extends AlertDialog {
         public ConnectDialog(Context context) {
             super(context);
             setTitle(String.format(getString(R.string.vpn_connect_to),
-                    mActiveProfile.getName()));
+                    mConnectingActor.getProfile().getName()));
             setButton(DialogInterface.BUTTON_POSITIVE,
                     getString(R.string.vpn_connect_button),
                     VpnSettings.this);
@@ -498,11 +512,11 @@ public class VpnSettings extends SettingsPreferenceFragment
             String error = mConnectingActor.validateInputs(d);
             if (error == null) {
                 mConnectingActor.connect(d);
-                removeDialog(DIALOG_CONNECT);
+                removeConnectDialog();
                 return;
             } else {
                 // dismissDialog(DIALOG_CONNECT);
-                removeDialog(DIALOG_CONNECT);
+                removeConnectDialog();
 
                 final Activity activity = getActivity();
                 // show error dialog
@@ -522,8 +536,7 @@ public class VpnSettings extends SettingsPreferenceFragment
                 mShowingDialog.show();
             }
         } else {
-            removeDialog(DIALOG_CONNECT);
-            changeState(mActiveProfile, VpnState.IDLE);
+            removeConnectDialog();
         }
     }