Nav: Fixed Tabbing initial activation from skipping the first item if it is tabbable through. (#787)

docs/CHANGELOG.txt

@@ -47,6 +47,7 @@ Other Changes:
 - Nav: Fixed pressing Escape to leave menu layer while in a popup or child window. (#787)
 - Nav, InputText: Fixed accidental menu toggling while typing non-ascii characters using AltGR. [@rokups] (#370)
 - Nav: Fixed using SetItemDefaultFocus() on windows with _NavFlattened flag. (#787)
+- Nav: Fixed Tabbing initial activation from skipping the first item if it is tabbable through. (#787)
 - Tables: Expose TableSetColumnEnabled() in public api. (#3935)
 - Tables: Better preserve widths when columns count changes. (#4046)
 - TabBar: Fixed mouse reordering with very fast movements (e.g. crossing multiple tabs in a single

imgui.cpp

@@ -3257,7 +3257,11 @@ bool ImGui::FocusableItemRegister(ImGuiWindow* window, ImGuiID id)
     const bool is_tab_stop = (g.CurrentItemFlags & (ImGuiItemFlags_NoTabStop | ImGuiItemFlags_Disabled)) == 0;
     window->DC.FocusCounterRegular++;
     if (is_tab_stop)
+    {
         window->DC.FocusCounterTabStop++;
+        if (g.NavId == id)
+            g.NavIdTabCounter = window->DC.FocusCounterTabStop;
+    }
 
     // Process TAB/Shift-TAB to tab *OUT* of the currently focused item.
     // (Note that we can always TAB out of a widget that doesn't allow tabbing in)
@@ -3787,12 +3791,14 @@ void ImGui::UpdateTabFocus()
     g.TabFocusPressed = (g.NavWindow && g.NavWindow->Active && !(g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs) && !g.IO.KeyCtrl && IsKeyPressedMap(ImGuiKey_Tab));
     if (g.ActiveId == 0 && g.TabFocusPressed)
     {
-        // Note that SetKeyboardFocusHere() sets the Next fields mid-frame. To be consistent we also
+        // - This path is only taken when no widget are active/tabbed-into yet.
-        // manipulate the Next fields even, even though they will be turned into Curr fields by the code below.
+        //   Subsequent tabbing will be processed by FocusableItemRegister()
+        // - Note that SetKeyboardFocusHere() sets the Next fields mid-frame. To be consistent we also
+        //   manipulate the Next fields here even though they will be turned into Curr fields below.
         g.TabFocusRequestNextWindow = g.NavWindow;
         g.TabFocusRequestNextCounterRegular = INT_MAX;
         if (g.NavId != 0 && g.NavIdTabCounter != INT_MAX)
-            g.TabFocusRequestNextCounterTabStop = g.NavIdTabCounter + 1 + (g.IO.KeyShift ? -1 : 1);
+            g.TabFocusRequestNextCounterTabStop = g.NavIdTabCounter + (g.IO.KeyShift ? -1 : 0);
         else
             g.TabFocusRequestNextCounterTabStop = g.IO.KeyShift ? -1 : 0;
     }
@@ -8828,7 +8834,6 @@ static void ImGui::NavProcessItem(ImGuiWindow* window, const ImRect& nav_bb, con
         g.NavLayer = window->DC.NavLayerCurrent;
         g.NavFocusScopeId = window->DC.NavFocusScopeIdCurrent;
         g.NavIdIsAlive = true;
-        g.NavIdTabCounter = window->DC.FocusCounterTabStop;
         window->NavRectRel[window->DC.NavLayerCurrent] = nav_bb_rel;    // Store item bounding box (relative to window position)
     }
 }

imgui.h

@@ -61,7 +61,7 @@ Index of this file:
 // Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals. Work in progress versions typically starts at XYY99 then bounce up to XYY00, XYY01 etc. when release tagging happens)
 #define IMGUI_VERSION               "1.83 WIP"
-#define IMGUI_VERSION_NUM           18207
+#define IMGUI_VERSION_NUM           18208
 #define IMGUI_CHECKVERSION()        ImGui::DebugCheckVersionAndDataLayout(IMGUI_VERSION, sizeof(ImGuiIO), sizeof(ImGuiStyle), sizeof(ImVec2), sizeof(ImVec4), sizeof(ImDrawVert), sizeof(ImDrawIdx))
 #define IMGUI_HAS_TABLE
 

imgui_demo.cpp

@@ -5501,7 +5501,7 @@ static void ShowDemoWindowMisc()
             ImGui::InputText("3", buf, IM_ARRAYSIZE(buf));
             ImGui::PushAllowKeyboardFocus(false);
             ImGui::InputText("4 (tab skip)", buf, IM_ARRAYSIZE(buf));
-            //ImGui::SameLine(); HelpMarker("Use ImGui::PushAllowKeyboardFocus(bool) to disable tabbing through certain widgets.");
+            ImGui::SameLine(); HelpMarker("Item won't be cycled through when using TAB or Shift+Tab.");
             ImGui::PopAllowKeyboardFocus();
             ImGui::InputText("5", buf, IM_ARRAYSIZE(buf));
             ImGui::TreePop();
@@ -5527,6 +5527,7 @@ static void ShowDemoWindowMisc()
             if (focus_3) ImGui::SetKeyboardFocusHere();
             ImGui::InputText("3 (tab skip)", buf, IM_ARRAYSIZE(buf));
             if (ImGui::IsItemActive()) has_focus = 3;
+            ImGui::SameLine(); HelpMarker("Item won't be cycled through when using TAB or Shift+Tab.");
             ImGui::PopAllowKeyboardFocus();
 
             if (has_focus)