Added an implementation of SetItemDefaultFocus() in the master branch for combo patterns to use and be more forward-compatible. (#787)

imgui.cpp

@@ -5884,6 +5884,15 @@ void ImGui::SetScrollHere(float center_y_ratio)
     SetScrollFromPosY(target_y, center_y_ratio);
 }
 
+// FIXME-NAV: This function is a placeholder for the upcoming Navigation branch + Focusing features.
+// In the current branch this function will only set the scrolling, in the navigation branch it will also set your navigation cursor.
+// Prefer using "SetItemDefaultFocus()" over "if (IsWindowAppearing()) SetScrollHere()" when applicable.
+void ImGui::SetItemDefaultFocus()
+{
+    if (IsWindowAppearing())
+        SetScrollHere();
+}
+
 void ImGui::SetKeyboardFocusHere(int offset)
 {
     IM_ASSERT(offset >= -1);    // -1 is allowed but not below
@@ -9186,7 +9195,7 @@ bool ImGui::Combo(const char* label, int* current_item, bool (*items_getter)(voi
         return false;
 
     // Display items
-    // FIXME-OPT: Use clipper (if we can disable it on the appearing frame to make sure our call to SetScrollHere() is processed)
+    // FIXME-OPT: Use clipper (but we need to disable it on the appearing frame to make sure our call to SetItemDefaultFocus() is processed)
     bool value_changed = false;
     for (int i = 0; i < items_count; i++)
     {
@@ -9200,8 +9209,8 @@ bool ImGui::Combo(const char* label, int* current_item, bool (*items_getter)(voi
             value_changed = true;
             *current_item = i;
         }
-        if (item_selected && IsWindowAppearing())
-            SetScrollHere();
+        if (item_selected)
+            SetItemDefaultFocus();
         PopID();
     }
 

imgui.h

@@ -178,9 +178,8 @@ namespace ImGui
     IMGUI_API float         GetScrollMaxY();                                                    // get maximum scrolling amount ~~ ContentSize.Y - WindowSize.Y
     IMGUI_API void          SetScrollX(float scroll_x);                                         // set scrolling amount [0..GetScrollMaxX()]
     IMGUI_API void          SetScrollY(float scroll_y);                                         // set scrolling amount [0..GetScrollMaxY()]
-    IMGUI_API void          SetScrollHere(float center_y_ratio = 0.5f);                         // adjust scrolling amount to make current cursor position visible. center_y_ratio=0.0: top, 0.5: center, 1.0: bottom.
+    IMGUI_API void          SetScrollHere(float center_y_ratio = 0.5f);                         // adjust scrolling amount to make current cursor position visible. center_y_ratio=0.0: top, 0.5: center, 1.0: bottom. When using to make a "default/current item" visible, consider using SetItemDefaultFocus() instead.
     IMGUI_API void          SetScrollFromPosY(float pos_y, float center_y_ratio = 0.5f);        // adjust scrolling amount to make given position valid. use GetCursorPos() or GetCursorStartPos()+offset to get valid positions.
-    IMGUI_API void          SetKeyboardFocusHere(int offset = 0);                               // focus keyboard on the next widget. Use positive 'offset' to access sub components of a multiple component widget. Use -1 to access previous widget.
     IMGUI_API void          SetStateStorage(ImGuiStorage* tree);                                // replace tree state storage with our own (if you want to manipulate it yourself, typically clear subsection of it)
     IMGUI_API ImGuiStorage* GetStateStorage();
 
@@ -426,6 +425,12 @@ namespace ImGui
     IMGUI_API void          StyleColorsDark(ImGuiStyle* dst = NULL);
     IMGUI_API void          StyleColorsLight(ImGuiStyle* dst = NULL);
 
+    // Focus
+    // (FIXME: Those functions will be reworked after we merge the navigation branch + have a pass at focusing/tabbing features.)
+    // (Prefer using "SetItemDefaultFocus()" over "if (IsWindowAppearing()) SetScrollHere()" when applicable, to make your code more forward compatible when navigation branch is merged)
+    IMGUI_API void          SetItemDefaultFocus();                                              // make last item the default focused item of a window (WIP navigation branch only). Pleaase use instead of SetScrollHere().
+    IMGUI_API void          SetKeyboardFocusHere(int offset = 0);                               // focus keyboard on the next widget. Use positive 'offset' to access sub components of a multiple component widget. Use -1 to access previous widget.
+
     // Utilities
     IMGUI_API bool          IsItemHovered(ImGuiHoveredFlags flags = 0);                         // is the last item hovered by mouse (and usable)?
     IMGUI_API bool          IsItemActive();                                                     // is the last item active? (e.g. button being held, text field being edited- items that don't interact will always return false)