Menus: rework to allow for an icon column (not yet exposed, but usable via internals) + fix menus being affected by style.SelectableTextAlign (#126)

docs/CHANGELOG.txt

@@ -53,6 +53,7 @@ Other Changes:
 - Tables: Fix invalid data in TableGetSortSpecs() when SpecsDirty flag is unset. (#4233)
 - TabBar: Fixed using more than 32 KB-worth of tab names. (#4176)
 - Drag and Drop: drop target highlight doesn't try to bypass host clipping rectangle. (#4281, #3272)
+- Menus: MenuItem() and BeginMenu() are not affected/overlapping when style.SelectableTextAlign is altered.
 - Fixed printf-style format checks on non-MinGW flavors. (#4183, #3592)
 - Fonts: Functions with a 'float size_pixels' parameter can accept zero if it is set in ImFontSize::SizePixels.
 - Fonts: Prefer using U+FFFD character for fallback instead of '?', if available. (#4269)

imgui_internal.h

@@ -1038,13 +1038,15 @@ struct IMGUI_API ImGuiMenuColumns
     ImU32       TotalWidth;
     ImU32       NextTotalWidth;
     ImU16       Spacing;
-    ImU16       OffsetShortcut;     // Offsets are locked in Update()
+    ImU16       OffsetIcon;         // Always zero for now
+    ImU16       OffsetLabel;        // Offsets are locked in Update()
+    ImU16       OffsetShortcut;
     ImU16       OffsetMark;
-    ImU16       Widths[3];          // Width of:   Label, Shortcut, Mark (accumulators for current frame)
+    ImU16       Widths[4];          // Width of:   Icon, Label, Shortcut, Mark  (accumulators for current frame)
 
     ImGuiMenuColumns() { memset(this, 0, sizeof(*this)); }
     void        Update(float spacing, bool window_reappearing);
-    float       DeclColumns(float w_label, float w_shortcut, float w_mark);
+    float       DeclColumns(float w_icon, float w_label, float w_shortcut, float w_mark);
     void        CalcNextTotalWidth(bool update_offsets);
 };
 
@@ -2440,6 +2442,9 @@ namespace ImGui
     IMGUI_API ImVec2        FindBestWindowPosForPopupEx(const ImVec2& ref_pos, const ImVec2& size, ImGuiDir* last_dir, const ImRect& r_outer, const ImRect& r_avoid, ImGuiPopupPositionPolicy policy);
     IMGUI_API bool          BeginViewportSideBar(const char* name, ImGuiViewport* viewport, ImGuiDir dir, float size, ImGuiWindowFlags window_flags);
 
+    // Menus
+    IMGUI_API bool          MenuItemEx(const char* label, const char* icon, const char* shortcut = NULL, bool selected = false, bool enabled = true);
+
     // Combos
     IMGUI_API bool          BeginComboPopup(ImGuiID popup_id, const ImRect& bb, ImGuiComboFlags flags);
     IMGUI_API bool          BeginComboPreview();

imgui_widgets.cpp

@@ -6614,19 +6614,21 @@ void ImGuiMenuColumns::CalcNextTotalWidth(bool update_offsets)
         want_spacing |= (width > 0);
         if (update_offsets)
         {
-            if (i == 1) { OffsetShortcut = offset; }
+            if (i == 1) { OffsetLabel = offset; }
-            if (i == 2) { OffsetMark = offset; }
+            if (i == 2) { OffsetShortcut = offset; }
+            if (i == 3) { OffsetMark = offset; }
         }
         offset += width;
     }
     NextTotalWidth = offset;
 }
 
-float ImGuiMenuColumns::DeclColumns(float w_label, float w_shortcut, float w_mark)
+float ImGuiMenuColumns::DeclColumns(float w_icon, float w_label, float w_shortcut, float w_mark)
 {
-    Widths[0] = ImMax(Widths[0], (ImU16)w_label);
+    Widths[0] = ImMax(Widths[0], (ImU16)w_icon);
-    Widths[1] = ImMax(Widths[1], (ImU16)w_shortcut);
+    Widths[1] = ImMax(Widths[1], (ImU16)w_label);
-    Widths[2] = ImMax(Widths[2], (ImU16)w_mark);
+    Widths[2] = ImMax(Widths[2], (ImU16)w_shortcut);
+    Widths[3] = ImMax(Widths[3], (ImU16)w_mark);
     CalcNextTotalWidth(false);
     return (float)ImMax(TotalWidth, NextTotalWidth);
 }
@@ -6818,6 +6820,10 @@ bool ImGui::BeginMenu(const char* label, bool enabled)
     // However the final position is going to be different! It is chosen by FindBestWindowPosForPopup().
     // e.g. Menus tend to overlap each other horizontally to amplify relative Z-ordering.
     ImVec2 popup_pos, pos = window->DC.CursorPos;
+    PushID(label);
+    if (!enabled)
+        PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_TextDisabled]);
+    const ImGuiMenuColumns* offsets = &window->DC.MenuColumns;
     if (window->DC.LayoutType == ImGuiLayoutType_Horizontal)
     {
         // Menu inside an horizontal menu bar
@@ -6827,7 +6833,9 @@ bool ImGui::BeginMenu(const char* label, bool enabled)
         window->DC.CursorPos.x += IM_FLOOR(style.ItemSpacing.x * 0.5f);
         PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(style.ItemSpacing.x * 2.0f, style.ItemSpacing.y));
         float w = label_size.x;
-        pressed = Selectable(label, menu_is_open, ImGuiSelectableFlags_NoHoldingActiveID | ImGuiSelectableFlags_SelectOnClick | ImGuiSelectableFlags_DontClosePopups | (!enabled ? ImGuiSelectableFlags_Disabled : 0), ImVec2(w, 0.0f));
+        ImVec2 text_pos(window->DC.CursorPos.x + offsets->OffsetLabel, window->DC.CursorPos.y + window->DC.CurrLineTextBaseOffset);
+        pressed = Selectable("", menu_is_open, ImGuiSelectableFlags_NoHoldingActiveID | ImGuiSelectableFlags_SelectOnClick | ImGuiSelectableFlags_DontClosePopups | (!enabled ? ImGuiSelectableFlags_Disabled : 0), ImVec2(w, 0.0f));
+        RenderText(text_pos, label);
         PopStyleVar();
         window->DC.CursorPos.x += IM_FLOOR(style.ItemSpacing.x * (-1.0f + 0.5f)); // -1 spacing to compensate the spacing added when Selectable() did a SameLine(). It would also work to call SameLine() ourselves after the PopStyleVar().
     }
@@ -6837,12 +6845,18 @@ bool ImGui::BeginMenu(const char* label, bool enabled)
         // (In a typical menu window where all items are BeginMenu() or MenuItem() calls, extra_w will always be 0.0f.
         //  Only when they are other items sticking out we're going to add spacing, yet only register minimum width into the layout system.
         popup_pos = ImVec2(pos.x, pos.y - style.WindowPadding.y);
-        float min_w = window->DC.MenuColumns.DeclColumns(label_size.x, 0.0f, IM_FLOOR(g.FontSize * 1.20f)); // Feedback to next frame
+        float icon_w = 0.0f; // FIXME: This not currently exposed for BeginMenu() however you can call window->DC.MenuColumns.DeclColumns(w, 0, 0, 0) yourself
+        float checkmark_w = IM_FLOOR(g.FontSize * 1.20f);
+        float min_w = window->DC.MenuColumns.DeclColumns(icon_w, label_size.x, 0.0f, checkmark_w); // Feedback to next frame
         float extra_w = ImMax(0.0f, GetContentRegionAvail().x - min_w);
-        pressed = Selectable(label, menu_is_open, ImGuiSelectableFlags_NoHoldingActiveID | ImGuiSelectableFlags_SelectOnClick | ImGuiSelectableFlags_DontClosePopups | ImGuiSelectableFlags_SpanAvailWidth | (!enabled ? ImGuiSelectableFlags_Disabled : 0), ImVec2(min_w, 0.0f));
+        ImVec2 text_pos(window->DC.CursorPos.x + offsets->OffsetLabel, window->DC.CursorPos.y + window->DC.CurrLineTextBaseOffset);
-        ImU32 text_col = GetColorU32(enabled ? ImGuiCol_Text : ImGuiCol_TextDisabled);
+        pressed = Selectable("", menu_is_open, ImGuiSelectableFlags_NoHoldingActiveID | ImGuiSelectableFlags_SelectOnClick | ImGuiSelectableFlags_DontClosePopups | ImGuiSelectableFlags_SpanAvailWidth | (!enabled ? ImGuiSelectableFlags_Disabled : 0), ImVec2(min_w, 0.0f));
-        RenderArrow(window->DrawList, pos + ImVec2(window->DC.MenuColumns.OffsetMark + extra_w + g.FontSize * 0.30f, 0.0f), text_col, ImGuiDir_Right);
+        RenderText(text_pos, label);
+        RenderArrow(window->DrawList, pos + ImVec2(offsets->OffsetMark + extra_w + g.FontSize * 0.30f, 0.0f), GetColorU32(ImGuiCol_Text), ImGuiDir_Right);
     }
+    if (!enabled)
+        PopStyleColor();
+    PopID();
 
     const bool hovered = enabled && ItemHoverable(window->DC.LastItemRect, id);
     if (menuset_is_open)
@@ -6958,7 +6972,7 @@ void ImGui::EndMenu()
     EndPopup();
 }
 
-bool ImGui::MenuItem(const char* label, const char* shortcut, bool selected, bool enabled)
+bool ImGui::MenuItemEx(const char* label, const char* icon, const char* shortcut, bool selected, bool enabled)
 {
     ImGuiWindow* window = GetCurrentWindow();
     if (window->SkipItems)
@@ -6973,6 +6987,10 @@ bool ImGui::MenuItem(const char* label, const char* shortcut, bool selected, boo
     // but I am unsure whether this should be kept at all. For now moved it to be an opt-in feature used by menus only.
     ImGuiSelectableFlags flags = ImGuiSelectableFlags_SelectOnRelease | ImGuiSelectableFlags_SetNavIdOnHover | (enabled ? 0 : ImGuiSelectableFlags_Disabled);
     bool pressed;
+    PushID(label);
+    if (!enabled)
+        PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_TextDisabled]);
+    const ImGuiMenuColumns* offsets = &window->DC.MenuColumns;
     if (window->DC.LayoutType == ImGuiLayoutType_Horizontal)
     {
         // Mimic the exact layout spacing of BeginMenu() to allow MenuItem() inside a menu bar, which is a little misleading but may be useful
@@ -6980,8 +6998,9 @@ bool ImGui::MenuItem(const char* label, const char* shortcut, bool selected, boo
         float w = label_size.x;
         window->DC.CursorPos.x += IM_FLOOR(style.ItemSpacing.x * 0.5f);
         PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(style.ItemSpacing.x * 2.0f, style.ItemSpacing.y));
-        pressed = Selectable(label, selected, flags, ImVec2(w, 0.0f));
+        pressed = Selectable("", selected, flags, ImVec2(w, 0.0f));
         PopStyleVar();
+        RenderText(pos + ImVec2(offsets->OffsetLabel, 0.0f), label);
         window->DC.CursorPos.x += IM_FLOOR(style.ItemSpacing.x * (-1.0f + 0.5f)); // -1 spacing to compensate the spacing added when Selectable() did a SameLine(). It would also work to call SameLine() ourselves after the PopStyleVar().
     }
     else
@@ -6989,27 +7008,40 @@ bool ImGui::MenuItem(const char* label, const char* shortcut, bool selected, boo
         // Menu item inside a vertical menu
         // (In a typical menu window where all items are BeginMenu() or MenuItem() calls, extra_w will always be 0.0f.
         //  Only when they are other items sticking out we're going to add spacing, yet only register minimum width into the layout system.
-        float shortcut_w = shortcut ? CalcTextSize(shortcut, NULL).x : 0.0f;
+        float icon_w = (icon && icon[0]) ? CalcTextSize(icon, NULL).x : 0.0f;
-        float min_w = window->DC.MenuColumns.DeclColumns(label_size.x, shortcut_w, IM_FLOOR(g.FontSize * 1.20f)); // Feedback for next frame
+        float shortcut_w = (shortcut && shortcut[0]) ? CalcTextSize(shortcut, NULL).x : 0.0f;
-        float extra_w = ImMax(0.0f, GetContentRegionAvail().x - min_w);
+        float checkmark_w = IM_FLOOR(g.FontSize * 1.20f);
-        pressed = Selectable(label, false, flags | ImGuiSelectableFlags_SpanAvailWidth, ImVec2(min_w, 0.0f));
+        float min_w = window->DC.MenuColumns.DeclColumns(icon_w, label_size.x, shortcut_w, checkmark_w); // Feedback for next frame
+        float stretch_w = ImMax(0.0f, GetContentRegionAvail().x - min_w);
+        pressed = Selectable("", false, flags | ImGuiSelectableFlags_SpanAvailWidth, ImVec2(min_w, 0.0f));
+        RenderText(pos + ImVec2(offsets->OffsetLabel, 0.0f), label);
+        if (icon_w > 0.0f)
+            RenderText(pos + ImVec2(offsets->OffsetIcon, 0.0f), icon);
         if (shortcut_w > 0.0f)
         {
-            PushStyleColor(ImGuiCol_Text, g.Style.Colors[ImGuiCol_TextDisabled]);
+            PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_TextDisabled]);
-            RenderText(pos + ImVec2(window->DC.MenuColumns.OffsetShortcut + extra_w, 0.0f), shortcut, NULL, false);
+            RenderText(pos + ImVec2(offsets->OffsetShortcut + stretch_w, 0.0f), shortcut, NULL, false);
             PopStyleColor();
         }
         if (selected)
-            RenderCheckMark(window->DrawList, pos + ImVec2(window->DC.MenuColumns.OffsetMark + extra_w + g.FontSize * 0.40f, g.FontSize * 0.134f * 0.5f), GetColorU32(enabled ? ImGuiCol_Text : ImGuiCol_TextDisabled), g.FontSize  * 0.866f);
+            RenderCheckMark(window->DrawList, pos + ImVec2(offsets->OffsetMark + stretch_w + g.FontSize * 0.40f, g.FontSize * 0.134f * 0.5f), GetColorU32(ImGuiCol_Text), g.FontSize  * 0.866f);
     }
+    if (!enabled)
+        PopStyleColor();
+    PopID();
 
     IMGUI_TEST_ENGINE_ITEM_INFO(window->DC.LastItemId, label, window->DC.LastItemStatusFlags | ImGuiItemStatusFlags_Checkable | (selected ? ImGuiItemStatusFlags_Checked : 0));
     return pressed;
 }
 
+bool ImGui::MenuItem(const char* label, const char* shortcut, bool selected, bool enabled)
+{
+    return MenuItemEx(label, NULL, shortcut, selected, enabled);
+}
+
 bool ImGui::MenuItem(const char* label, const char* shortcut, bool* p_selected, bool enabled)
 {
-    if (MenuItem(label, shortcut, p_selected ? *p_selected : false, enabled))
+    if (MenuItemEx(label, NULL, shortcut, p_selected ? *p_selected : false, enabled))
     {
         if (p_selected)
             *p_selected = !*p_selected;