Fixed SetKeyboardFocusHere() focusing wrong widget when target widget…

… disappears. (ocornut#432)
rokups · Jul 15, 2020 · c8940f2 · c8940f2
1 parent eefae08
commit c8940f2
Show file tree

Hide file tree

Showing 3 changed files with 25 additions and 4 deletions.
diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
@@ -54,6 +54,7 @@ Other Changes:
 - ImDrawList: Fixed minor bug introduced in 1.75 where AddCircle() with 12 segments would generate
   an extra vertex. (This bug was mistakenly marked as fixed in earlier 1.77 release). [@ShironekoBen]
 - Backends: OpenGL3: Added support for glad2 loader. (#3330) [@moritz-h]
+- Misc: Fixed SetKeyboardFocusHere() focusing wrong widget when target widget disappears. (#432) [@rokups]
 
 
 -----------------------------------------------------------------------

diff --git a/imgui.cpp b/imgui.cpp
@@ -3118,7 +3118,7 @@ bool ImGui::FocusableItemRegister(ImGuiWindow* window, ImGuiID id)
     // Handle focus requests
     if (g.FocusRequestCurrWindow == window)
     {
-        if (window->DC.FocusCounterRegular == g.FocusRequestCurrCounterRegular)
+        if (window->DC.FocusCounterRegular == g.FocusRequestCurrCounterRegular && (g.FocusRequestCurrItemId == 0 || g.FocusRequestCurrItemId == id))
             return true;
         if (is_tab_stop && window->DC.FocusCounterTabStop == g.FocusRequestCurrCounterTabStop)
         {
@@ -3566,6 +3566,7 @@ void ImGui::UpdateTabFocus()
     // Turn queued focus request into current one
     g.FocusRequestCurrWindow = NULL;
     g.FocusRequestCurrCounterRegular = g.FocusRequestCurrCounterTabStop = INT_MAX;
+    g.FocusRequestCurrItemId = 0;
     if (g.FocusRequestNextWindow != NULL)
     {
         ImGuiWindow* window = g.FocusRequestNextWindow;
@@ -3574,6 +3575,8 @@ void ImGui::UpdateTabFocus()
             g.FocusRequestCurrCounterRegular = ImModPositive(g.FocusRequestNextCounterRegular, window->DC.FocusCounterRegular + 1);
         if (g.FocusRequestNextCounterTabStop != INT_MAX && window->DC.FocusCounterTabStop != -1)
             g.FocusRequestCurrCounterTabStop = ImModPositive(g.FocusRequestNextCounterTabStop, window->DC.FocusCounterTabStop + 1);
+        if (g.FocusRequestNextItemId != 0)
+            g.FocusRequestCurrItemId = g.FocusRequestNextItemId;
         g.FocusRequestNextWindow = NULL;
         g.FocusRequestNextCounterRegular = g.FocusRequestNextCounterTabStop = INT_MAX;
     }
@@ -6594,9 +6597,23 @@ void ImGui::SetKeyboardFocusHere(int offset)
     IM_ASSERT(offset >= -1);    // -1 is allowed but not below
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
-    g.FocusRequestNextWindow = window;
-    g.FocusRequestNextCounterRegular = window->DC.FocusCounterRegular + 1 + offset;
-    g.FocusRequestNextCounterTabStop = INT_MAX;
+    int focus_counter = window->DC.FocusCounterRegular + 1 + offset;
+    if (offset < 0)
+    {
+        // Handle negative offset on next frame, but only focus previous item if it does not disappear
+        g.FocusRequestNextItemId = window->DC.LastItemId;
+        g.FocusRequestNextWindow = window;
+        g.FocusRequestNextCounterRegular = focus_counter;
+        g.FocusRequestNextCounterTabStop = INT_MAX;
+    }
+    else
+    {
+        // Handle non-negative offset on current frame, it is ok if next element disappears on next frame
+        g.FocusRequestCurrWindow = window;
+        g.FocusRequestCurrItemId = 0;
+        g.FocusRequestCurrCounterRegular = focus_counter;
+        g.FocusRequestCurrCounterTabStop = INT_MAX;
+    }
 }
 
 void ImGui::SetItemDefaultFocus()

diff --git a/imgui_internal.h b/imgui_internal.h
@@ -1228,8 +1228,10 @@ struct ImGuiContext
     ImGuiWindow*            FocusRequestNextWindow;             //
     int                     FocusRequestCurrCounterRegular;     // Any item being requested for focus, stored as an index (we on layout to be stable between the frame pressing TAB and the next frame, semi-ouch)
     int                     FocusRequestCurrCounterTabStop;     // Tab item being requested for focus, stored as an index
+    int                     FocusRequestCurrItemId;             //
     int                     FocusRequestNextCounterRegular;     // Stored for next frame
     int                     FocusRequestNextCounterTabStop;     // "
+    int                     FocusRequestNextItemId;             //
     bool                    FocusTabPressed;                    //
 
     // Render
@@ -1400,6 +1402,7 @@ struct ImGuiContext
         FocusRequestCurrWindow = FocusRequestNextWindow = NULL;
         FocusRequestCurrCounterRegular = FocusRequestCurrCounterTabStop = INT_MAX;
         FocusRequestNextCounterRegular = FocusRequestNextCounterTabStop = INT_MAX;
+        FocusRequestCurrItemId = FocusRequestNextItemId = 0;
         FocusTabPressed = false;
 
         DimBgRatio = 0.0f;