From 9243d674ef9c237878bd732304c05de67210ecae Mon Sep 17 00:00:00 2001
From: Bertrand Bellenot <bertrand.bellenot@cern.ch>
Date: Mon, 19 Jan 2015 13:36:49 +0100
Subject: [PATCH] Fix Jira issue #ROOT-6985: cannot open TBrowser() from ROOT
 prompt

Fix a crash in TRootBrowser when having the option Canvas.ShowEditor: true in the .rootrc file.
---
 gui/gui/src/TRootBrowser.cxx |  2 +-
 gui/gui/src/TRootCanvas.cxx  | 30 +++++++++++++++++-------------
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/gui/gui/src/TRootBrowser.cxx b/gui/gui/src/TRootBrowser.cxx
index 9723d17..6371f86 100644
--- a/gui/gui/src/TRootBrowser.cxx
+++ b/gui/gui/src/TRootBrowser.cxx
@@ -1136,7 +1136,7 @@ void TRootBrowser::StopEmbedding(const char *name, TGLayoutHints *layout)
    if (name && strlen(name)) {
       SetTabTitle(name, fEditPos, fEditSubPos);
    }
-   fEditTab->Selected(fEditSubPos);
+   if (fEditTab) fEditTab->Selected(fEditSubPos);
    fEditFrame = fEditTab = 0;
    fEditPos = fEditSubPos = -1;
 }
diff --git a/gui/gui/src/TRootCanvas.cxx b/gui/gui/src/TRootCanvas.cxx
index 96a8fc1..06515a9 100644
--- a/gui/gui/src/TRootCanvas.cxx
+++ b/gui/gui/src/TRootCanvas.cxx
@@ -1481,19 +1481,23 @@ void TRootCanvas::ShowEditor(Bool_t show)
          fEmbedded = kTRUE;
          if (show && (!fEditor || !((TGedEditor *)fEditor)->IsMapped())) {
             if (!browser->GetTabLeft()->GetTabTab("Pad Editor")) {
-               browser->StartEmbedding(TRootBrowser::kLeft);
-               if (!fEditor)
-                  fEditor = TVirtualPadEditor::GetPadEditor(kTRUE);
-               else {
-                  ((TGedEditor *)fEditor)->ReparentWindow(fClient->GetRoot());
-                  ((TGedEditor *)fEditor)->MapWindow();
-               }
-               browser->StopEmbedding("Pad Editor");
-               fEditor->SetGlobal(kFALSE);
-               gROOT->GetListOfCleanups()->Remove((TGedEditor *)fEditor);
-               if (fEditor) {
-                  ((TGedEditor *)fEditor)->SetCanvas(fCanvas);
-                  ((TGedEditor *)fEditor)->SetModel(fCanvas, fCanvas, kButton1Down);
+               if (browser->GetActFrame()) { //already in edit mode
+                  TTimer::SingleShot(200, "TRootCanvas", this, "ShowEditor(=kTRUE)");
+               } else {
+                  browser->StartEmbedding(TRootBrowser::kLeft);
+                  if (!fEditor)
+                     fEditor = TVirtualPadEditor::GetPadEditor(kTRUE);
+                  else {
+                     ((TGedEditor *)fEditor)->ReparentWindow(fClient->GetRoot());
+                     ((TGedEditor *)fEditor)->MapWindow();
+                  }
+                  browser->StopEmbedding("Pad Editor");
+                  fEditor->SetGlobal(kFALSE);
+                  gROOT->GetListOfCleanups()->Remove((TGedEditor *)fEditor);
+                  if (fEditor) {
+                     ((TGedEditor *)fEditor)->SetCanvas(fCanvas);
+                     ((TGedEditor *)fEditor)->SetModel(fCanvas, fCanvas, kButton1Down);
+                  }
                }
             }
             else
-- 
1.8.2