Focus, Nav: Merged bits from RangeSelect features to enable early manipulation of focus scope for styling purpose.

FocusScopeId is tracked by nav scoring/request and stored in result.
It's all rather WIP and we should reorganize the SetNavIDXXX functions fiasco at some point (soon?).
Didn't separate FocusScope from SelectionScope for now, will re-investigate this later, this is the minimum commit to be able to do some styling.

imgui.cpp

@@ -2752,19 +2752,21 @@ void ImGui::GcAwakeTransientWindowBuffers(ImGuiWindow* window)
     window->MemoryDrawListIdxCapacity = window->MemoryDrawListVtxCapacity = 0;
 }
 
-void ImGui::SetNavID(ImGuiID id, int nav_layer)
+// FIXME-NAV: Refactor those functions into a single, more explicit one.
+void ImGui::SetNavID(ImGuiID id, int nav_layer, int focus_scope_id)
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(g.NavWindow);
     IM_ASSERT(nav_layer == 0 || nav_layer == 1);
     g.NavId = id;
+    g.NavFocusScopeId = focus_scope_id;
     g.NavWindow->NavLastIds[nav_layer] = id;
 }
 
-void ImGui::SetNavIDWithRectRel(ImGuiID id, int nav_layer, const ImRect& rect_rel)
+void ImGui::SetNavIDWithRectRel(ImGuiID id, int nav_layer, int focus_scope_id, const ImRect& rect_rel)
 {
     ImGuiContext& g = *GImGui;
-    SetNavID(id, nav_layer);
+    SetNavID(id, nav_layer, focus_scope_id);
     g.NavWindow->NavRectRel[nav_layer] = rect_rel;
     g.NavMousePosDirty = true;
     g.NavDisableHighlight = false;
@@ -2809,13 +2811,15 @@ void ImGui::SetFocusID(ImGuiID id, ImGuiWindow* window)
     ImGuiContext& g = *GImGui;
     IM_ASSERT(id != 0);
 
-    // Assume that SetFocusID() is called in the context where its NavLayer is the current layer, which is the case everywhere we call it.
+    // Assume that SetFocusID() is called in the context where its window->DC.NavLayerCurrent and window->DC.NavFocusScopeIdCurrent are valid.
+    // Note that window may be != g.CurrentWindow (e.g. SetFocusID call in InputTextEx for multi-line text)
     const ImGuiNavLayer nav_layer = window->DC.NavLayerCurrent;
     if (g.NavWindow != window)
         g.NavInitRequest = false;
-    g.NavId = id;
     g.NavWindow = window;
+    g.NavId = id;
     g.NavLayer = nav_layer;
+    g.NavFocusScopeId = window->DC.NavFocusScopeIdCurrent;
     window->NavLastIds[nav_layer] = id;
     if (window->DC.LastItemId == id)
         window->NavRectRel[nav_layer] = ImRect(window->DC.LastItemRect.Min - window->Pos, window->DC.LastItemRect.Max - window->Pos);
@@ -5845,6 +5849,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         window->DC.NavLayerCurrentMask = (1 << ImGuiNavLayer_Main);
         window->DC.NavLayerActiveMask = window->DC.NavLayerActiveMaskNext;
         window->DC.NavLayerActiveMaskNext = 0x00;
+        window->DC.NavFocusScopeIdCurrent = 0;
         window->DC.NavHideHighlightOneFrame = false;
         window->DC.NavHasScroll = (window->ScrollMax.y > 0.0f);
 
@@ -6047,6 +6052,7 @@ void ImGui::FocusWindow(ImGuiWindow* window)
             g.NavMousePosDirty = true;
         g.NavInitRequest = false;
         g.NavId = window ? window->NavLastIds[0] : 0; // Restore NavId
+        g.NavFocusScopeId = 0;
         g.NavIdIsAlive = false;
         g.NavLayer = ImGuiNavLayer_Main;
         //IMGUI_DEBUG_LOG("FocusWindow(\"%s\")\n", window ? window->Name : NULL);
@@ -8039,21 +8045,22 @@ static void ImGui::NavProcessItem(ImGuiWindow* window, const ImRect& nav_bb, con
 #endif
         if (new_best)
         {
-            result->ID = id;
-            result->SelectScopeId = g.MultiSelectScopeId;
             result->Window = window;
+            result->ID = id;
+            result->FocusScopeId = window->DC.NavFocusScopeIdCurrent;
             result->RectRel = nav_bb_rel;
         }
 
+        // Features like PageUp/PageDown need to maintain a separate score for the visible set of items.
         const float VISIBLE_RATIO = 0.70f;
         if ((g.NavMoveRequestFlags & ImGuiNavMoveFlags_AlsoScoreVisibleSet) && window->ClipRect.Overlaps(nav_bb))
             if (ImClamp(nav_bb.Max.y, window->ClipRect.Min.y, window->ClipRect.Max.y) - ImClamp(nav_bb.Min.y, window->ClipRect.Min.y, window->ClipRect.Max.y) >= (nav_bb.Max.y - nav_bb.Min.y) * VISIBLE_RATIO)
                 if (NavScoreItem(&g.NavMoveResultLocalVisibleSet, nav_bb))
                 {
                     result = &g.NavMoveResultLocalVisibleSet;
-                    result->ID = id;
-                    result->SelectScopeId = g.MultiSelectScopeId;
                     result->Window = window;
+                    result->ID = id;
+                    result->FocusScopeId = window->DC.NavFocusScopeIdCurrent;
                     result->RectRel = nav_bb_rel;
                 }
     }
@@ -8063,6 +8070,7 @@ static void ImGui::NavProcessItem(ImGuiWindow* window, const ImRect& nav_bb, con
     {
         g.NavWindow = window;                                           // Always refresh g.NavWindow, because some operations such as FocusItem() don't have a window.
         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)
@@ -8153,10 +8161,11 @@ static void NavRestoreLayer(ImGuiNavLayer layer)
     g.NavLayer = layer;
     if (layer == 0)
         g.NavWindow = ImGui::NavRestoreLastChildNavWindow(g.NavWindow);
-    if (layer == 0 && g.NavWindow->NavLastIds[0] != 0)
-        ImGui::SetNavIDWithRectRel(g.NavWindow->NavLastIds[0], layer, g.NavWindow->NavRectRel[0]);
+    ImGuiWindow* window = g.NavWindow;
+    if (layer == 0 && window->NavLastIds[0] != 0)
+        ImGui::SetNavIDWithRectRel(window->NavLastIds[0], layer, 0, window->NavRectRel[0]);
     else
-        ImGui::NavInitWindow(g.NavWindow, true);
+        ImGui::NavInitWindow(window, true);
 }
 
 static inline void ImGui::NavUpdateAnyRequestFlag()
@@ -8179,7 +8188,7 @@ void ImGui::NavInitWindow(ImGuiWindow* window, bool force_reinit)
     //IMGUI_DEBUG_LOG("[Nav] NavInitWindow() init_for_nav=%d, window=\"%s\", layer=%d\n", init_for_nav, window->Name, g.NavLayer);
     if (init_for_nav)
     {
-        SetNavID(0, g.NavLayer);
+        SetNavID(0, g.NavLayer, 0);
         g.NavInitRequest = true;
         g.NavInitRequestFromMove = false;
         g.NavInitResultId = 0;
@@ -8189,6 +8198,7 @@ void ImGui::NavInitWindow(ImGuiWindow* window, bool force_reinit)
     else
     {
         g.NavId = window->NavLastIds[0];
+        g.NavFocusScopeId = 0;
     }
 }
 
@@ -8295,9 +8305,9 @@ static void ImGui::NavUpdate()
         // Apply result from previous navigation init request (will typically select the first item, unless SetItemDefaultFocus() has been called)
         //IMGUI_DEBUG_LOG("[Nav] Apply NavInitRequest result: 0x%08X Layer %d in \"%s\"\n", g.NavInitResultId, g.NavLayer, g.NavWindow->Name);
         if (g.NavInitRequestFromMove)
-            SetNavIDWithRectRel(g.NavInitResultId, g.NavLayer, g.NavInitResultRectRel);
+            SetNavIDWithRectRel(g.NavInitResultId, g.NavLayer, 0, g.NavInitResultRectRel);
         else
-            SetNavID(g.NavInitResultId, g.NavLayer);
+            SetNavID(g.NavInitResultId, g.NavLayer, 0);
         g.NavWindow->NavRectRel[g.NavLayer] = g.NavInitResultRectRel;
     }
     g.NavInitRequest = false;
@@ -8364,7 +8374,7 @@ static void ImGui::NavUpdate()
             ImGuiWindow* parent_window = g.NavWindow->ParentWindow;
             IM_ASSERT(child_window->ChildId != 0);
             FocusWindow(parent_window);
-            SetNavID(child_window->ChildId, 0);
+            SetNavID(child_window->ChildId, 0, 0);
             // Reassigning with same value, we're being explicit here.
             g.NavIdIsAlive = false;     // -V1048
             if (g.NavDisableMouseHover)
@@ -8386,7 +8396,7 @@ static void ImGui::NavUpdate()
             // Clear NavLastId for popups but keep it for regular child window so we can leave one and come back where we were
             if (g.NavWindow && ((g.NavWindow->Flags & ImGuiWindowFlags_Popup) || !(g.NavWindow->Flags & ImGuiWindowFlags_ChildWindow)))
                 g.NavWindow->NavLastIds[0] = 0;
-            g.NavId = 0;
+            g.NavId = g.NavFocusScopeId = 0;
         }
     }
 
@@ -8506,7 +8516,7 @@ static void ImGui::NavUpdate()
             float pad = window->CalcFontSize() * 0.5f;
             window_rect_rel.Expand(ImVec2(-ImMin(window_rect_rel.GetWidth(), pad), -ImMin(window_rect_rel.GetHeight(), pad))); // Terrible approximation for the intent of starting navigation from first fully visible item
             window->NavRectRel[g.NavLayer].ClipWith(window_rect_rel);
-            g.NavId = 0;
+            g.NavId = g.NavFocusScopeId = 0;
         }
         g.NavMoveFromClampedRefRect = false;
     }
@@ -8586,9 +8596,10 @@ static void ImGui::NavUpdateMoveResult()
     {
         // Don't set NavJustMovedToId if just landed on the same spot (which may happen with ImGuiNavMoveFlags_AllowCurrentNavId)
         g.NavJustMovedToId = result->ID;
-        g.NavJustMovedToMultiSelectScopeId = result->SelectScopeId;
+        g.NavJustMovedToFocusScopeId = result->FocusScopeId;
+
     }
-    SetNavIDWithRectRel(result->ID, g.NavLayer, result->RectRel);
+    SetNavIDWithRectRel(result->ID, g.NavLayer, result->FocusScopeId, result->RectRel);
     g.NavMoveFromClampedRefRect = false;
 }
 

imgui_internal.h

@@ -877,16 +877,16 @@ struct ImDrawDataBuilder
 
 struct ImGuiNavMoveResult
 {
-    ImGuiID       ID;           // Best candidate
-    ImGuiID       SelectScopeId;// Best candidate window current selectable group ID
-    ImGuiWindow*  Window;       // Best candidate window
-    float         DistBox;      // Best candidate box distance to current NavId
-    float         DistCenter;   // Best candidate center distance to current NavId
-    float         DistAxial;
-    ImRect        RectRel;      // Best candidate bounding box in window relative space
+    ImGuiWindow*    Window;             // Best candidate window
+    ImGuiID         ID;                 // Best candidate ID
+    ImGuiID         FocusScopeId;       // Best candidate focus scope ID
+    float           DistBox;            // Best candidate box distance to current NavId
+    float           DistCenter;         // Best candidate center distance to current NavId
+    float           DistAxial;
+    ImRect          RectRel;            // Best candidate bounding box in window relative space
 
     ImGuiNavMoveResult() { Clear(); }
-    void Clear()         { ID = SelectScopeId = 0; Window = NULL; DistBox = DistCenter = DistAxial = FLT_MAX; RectRel = ImRect(); }
+    void Clear()         { Window = NULL; ID = FocusScopeId = 0; DistBox = DistCenter = DistAxial = FLT_MAX; RectRel = ImRect(); }
 };
 
 enum ImGuiNextWindowDataFlags_
@@ -920,7 +920,7 @@ struct ImGuiNextWindowData
     ImVec2                      MenuBarOffsetMinVal;    // *Always on* This is not exposed publicly, so we don't clear it.
 
     ImGuiNextWindowData()       { memset(this, 0, sizeof(*this)); }
-    inline void ClearFlags()    { Flags = ImGuiNextWindowDataFlags_None; } // Also cleared by ItemAdd()
+    inline void ClearFlags()    { Flags = ImGuiNextWindowDataFlags_None; }
 };
 
 enum ImGuiNextItemDataFlags_
@@ -933,12 +933,13 @@ enum ImGuiNextItemDataFlags_
 struct ImGuiNextItemData
 {
     ImGuiNextItemDataFlags      Flags;
-    float                       Width;          // Set by SetNextItemWidth().
-    bool                        OpenVal;        // Set by SetNextItemOpen() function.
+    float                       Width;          // Set by SetNextItemWidth()
+    ImGuiID                     FocusScopeId;   // Set by SetNextItemMultiSelectData() (!= 0 signify value has been set, so it's an alternate version of HasSelectionData, we don't use Flags for this because they are cleared too early. This is mostly used for debugging)
     ImGuiCond                   OpenCond;
+    bool                        OpenVal;        // Set by SetNextItemOpen()
 
     ImGuiNextItemData()         { memset(this, 0, sizeof(*this)); }
-    inline void ClearFlags()    { Flags = ImGuiNextItemDataFlags_None; }
+    inline void ClearFlags()    { Flags = ImGuiNextItemDataFlags_None; } // Also cleared manually by ItemAdd()!
 };
 
 //-----------------------------------------------------------------------------
@@ -1038,13 +1039,15 @@ struct ImGuiContext
     // Gamepad/keyboard Navigation
     ImGuiWindow*            NavWindow;                          // Focused window for navigation. Could be called 'FocusWindow'
     ImGuiID                 NavId;                              // Focused item for navigation
+    ImGuiID                 NavFocusScopeId;
     ImGuiID                 NavActivateId;                      // ~~ (g.ActiveId == 0) && IsNavInputPressed(ImGuiNavInput_Activate) ? NavId : 0, also set when calling ActivateItem()
     ImGuiID                 NavActivateDownId;                  // ~~ IsNavInputDown(ImGuiNavInput_Activate) ? NavId : 0
     ImGuiID                 NavActivatePressedId;               // ~~ IsNavInputPressed(ImGuiNavInput_Activate) ? NavId : 0
     ImGuiID                 NavInputId;                         // ~~ IsNavInputPressed(ImGuiNavInput_Input) ? NavId : 0
     ImGuiID                 NavJustTabbedId;                    // Just tabbed to this id.
     ImGuiID                 NavJustMovedToId;                   // Just navigated to this id (result of a successfully MoveRequest).
-    ImGuiID                 NavJustMovedToMultiSelectScopeId;   // Just navigated to this select scope id (result of a successfully MoveRequest).
+    ImGuiID                 NavJustMovedToFocusScopeId;         // Just navigated to this focus scope id (result of a successfully MoveRequest).
+
     ImGuiID                 NavNextActivateId;                  // Set by ActivateItem(), queued until next frame.
     ImGuiInputSource        NavInputSource;                     // Keyboard or Gamepad mode? THIS WILL ONLY BE None or NavGamepad or NavKeyboard.
     ImRect                  NavScoringRectScreen;               // Rectangle used for scoring, in screen space. Based of window->DC.NavRefRectRel[], modified for directional navigation scoring.
@@ -1085,10 +1088,6 @@ struct ImGuiContext
     int                     FocusRequestNextCounterTabStop;     // "
     bool                    FocusTabPressed;                    //
 
-    // Range-Select/Multi-Select
-    // [This is unused in this branch, but left here to facilitate merging/syncing multiple branches]
-    ImGuiID                 MultiSelectScopeId;
-
     // Render
     ImDrawData              DrawData;                           // Main ImDrawData instance to pass render information to the user
     ImDrawDataBuilder       DrawDataBuilder;
@@ -1218,8 +1217,8 @@ struct ImGuiContext
         LastActiveIdTimer = 0.0f;
 
         NavWindow = NULL;
-        NavId = NavActivateId = NavActivateDownId = NavActivatePressedId = NavInputId = 0;
-        NavJustTabbedId = NavJustMovedToId = NavJustMovedToMultiSelectScopeId = NavNextActivateId = 0;
+        NavId = NavFocusScopeId = NavActivateId = NavActivateDownId = NavActivatePressedId = NavInputId = 0;
+        NavJustTabbedId = NavJustMovedToId = NavJustMovedToFocusScopeId = NavNextActivateId = 0;
         NavInputSource = ImGuiInputSource_None;
         NavScoringRectScreen = ImRect();
         NavScoringCount = 0;
@@ -1247,8 +1246,6 @@ struct ImGuiContext
         FocusRequestNextCounterRegular = FocusRequestNextCounterTabStop = INT_MAX;
         FocusTabPressed = false;
 
-        MultiSelectScopeId = 0;
-
         DimBgRatio = 0.0f;
         BackgroundDrawList._OwnerName = "##Background"; // Give it a name for debugging
         ForegroundDrawList._OwnerName = "##Foreground"; // Give it a name for debugging
@@ -1334,6 +1331,7 @@ struct IMGUI_API ImGuiWindowTempData
     int                     NavLayerCurrentMask;    // = (1 << NavLayerCurrent) used by ItemAdd prior to clipping.
     int                     NavLayerActiveMask;     // Which layer have been written to (result from previous frame)
     int                     NavLayerActiveMaskNext; // Which layer have been written to (buffer for current frame)
+    ImGuiID                 NavFocusScopeIdCurrent; // Current focus scope ID while appending
     bool                    NavHideHighlightOneFrame;
     bool                    NavHasScroll;           // Set when scrolling can be used (ScrollMax > 0.0f)
 
@@ -1378,6 +1376,7 @@ struct IMGUI_API ImGuiWindowTempData
         NavLayerActiveMask = NavLayerActiveMaskNext = 0x00;
         NavLayerCurrent = ImGuiNavLayer_Main;
         NavLayerCurrentMask = (1 << ImGuiNavLayer_Main);
+        NavFocusScopeIdCurrent = 0;
         NavHideHighlightOneFrame = false;
         NavHasScroll = false;
 
@@ -1701,8 +1700,8 @@ namespace ImGui
     IMGUI_API ImVec2        GetNavInputAmount2d(ImGuiNavDirSourceFlags dir_sources, ImGuiInputReadMode mode, float slow_factor = 0.0f, float fast_factor = 0.0f);
     IMGUI_API int           CalcTypematicRepeatAmount(float t0, float t1, float repeat_delay, float repeat_rate);
     IMGUI_API void          ActivateItem(ImGuiID id);   // Remotely activate a button, checkbox, tree node etc. given its unique ID. activation is queued and processed on the next frame when the item is encountered again.
-    IMGUI_API void          SetNavID(ImGuiID id, int nav_layer);
-    IMGUI_API void          SetNavIDWithRectRel(ImGuiID id, int nav_layer, const ImRect& rect_rel);
+    IMGUI_API void          SetNavID(ImGuiID id, int nav_layer, int focus_scope_id);
+    IMGUI_API void          SetNavIDWithRectRel(ImGuiID id, int nav_layer, int focus_scope_id, const ImRect& rect_rel);
 
     // Inputs
     // FIXME: Eventually we should aim to move e.g. IsActiveIdUsingKey() into IsKeyXXX functions.

imgui_widgets.cpp

@@ -5312,9 +5312,9 @@ bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* l
 
     bool hovered, held;
     bool pressed = ButtonBehavior(interact_bb, id, &hovered, &held, button_flags);
+    bool toggled = false;
     if (!is_leaf)
     {
-        bool toggled = false;
         if (pressed)
         {
             if ((flags & (ImGuiTreeNodeFlags_OpenOnArrow | ImGuiTreeNodeFlags_OpenOnDoubleClick)) == 0 || (g.NavActivateId == id))
@@ -5444,7 +5444,7 @@ void ImGui::TreePop()
     if (g.NavMoveDir == ImGuiDir_Left && g.NavWindow == window && NavMoveRequestButNoResultYet())
         if (g.NavIdIsAlive && (window->DC.TreeJumpToParentOnPopMask & tree_depth_mask))
         {
-            SetNavID(window->IDStack.back(), g.NavLayer);
+            SetNavID(window->IDStack.back(), g.NavLayer, 0);
             NavMoveRequestCancel();
         }
     window->DC.TreeJumpToParentOnPopMask &= tree_depth_mask - 1;
@@ -5600,7 +5600,7 @@ bool ImGui::Selectable(const char* label, bool selected, ImGuiSelectableFlags fl
         if (!g.NavDisableMouseHover && g.NavWindow == window && g.NavLayer == window->DC.NavLayerCurrent)
         {
             g.NavDisableHighlight = true;
-            SetNavID(id, window->DC.NavLayerCurrent);
+            SetNavID(id, window->DC.NavLayerCurrent, window->DC.NavFocusScopeIdCurrent);
         }
     }
     if (pressed)
@@ -6077,7 +6077,7 @@ void ImGui::EndMenuBar()
             const ImGuiNavLayer layer = ImGuiNavLayer_Menu;
             IM_ASSERT(window->DC.NavLayerActiveMaskNext & (1 << layer)); // Sanity check
             FocusWindow(window);
-            SetNavIDWithRectRel(window->NavLastIds[layer], layer, window->NavRectRel[layer]);
+            SetNavIDWithRectRel(window->NavLastIds[layer], layer, 0, window->NavRectRel[layer]);
             g.NavLayer = layer;
             g.NavDisableHighlight = true; // Hide highlight for the current frame so we don't see the intermediary selection.
             g.NavMoveRequestForward = ImGuiNavForward_ForwardQueued;