Added ActivateItem(), GetItemID() functions.

imgui.cpp

@@ -2837,6 +2837,11 @@ static void NavUpdate()
         IM_ASSERT(g.NavActivateDownId == g.NavActivateId);
     g.NavMoveRequest = false;
 
+    // Process explicit activation request
+    if (g.NavNextActivateId != 0)
+        g.NavActivateId = g.NavActivateDownId = g.NavInputId = g.NavNextActivateId;
+    g.NavNextActivateId = 0;
+
     // Initiate directional inputs request
     const int allowed_dir_flags = (g.ActiveId == 0) ? ~0 : g.ActiveIdAllowNavDirFlags;
     if (g.NavMoveRequestForwardStep == 0)
@@ -6379,6 +6384,18 @@ void ImGui::SetScrollHere(float center_y_ratio)
     SetScrollFromPosY(target_y, center_y_ratio);
 }
 
+void ImGui::ActivateItem(ImGuiID id)
+{
+    ImGuiContext& g = *GImGui;
+    g.NavNextActivateId = id;
+}
+
+ImGuiID ImGui::GetItemID()
+{
+    ImGuiContext& g = *GImGui;
+    return g.CurrentWindow->DC.LastItemId;
+}
+
 void ImGui::SetKeyboardFocusHere(int offset)
 {
     IM_ASSERT(offset >= -1);    // -1 is allowed but not below

imgui.h

@@ -177,7 +177,6 @@ namespace ImGui
     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          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);  // FIXME-NAVIGATION          // 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();
 
@@ -416,6 +415,11 @@ namespace ImGui
     // Styles
     IMGUI_API void          StyleColorsClassic(ImGuiStyle* dst = NULL);
 
+    // Focus, Activation
+    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 ImGuiID       GetItemID();                                                        // get id of previous item, generally ~GetID(label)
+    IMGUI_API void          SetKeyboardFocusHere(int offset = 0);  // FIXME-NAVIGATION          // 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();                                                    // is the last item hovered by mouse (and usable)? or we are currently using Nav and the item is focused.
     IMGUI_API bool          IsItemRectHovered();                                                // is the last item hovered by mouse? even if another item is active or window is blocked by popup while we are hovering this

imgui_demo.cpp

@@ -1754,6 +1754,11 @@ void ImGui::ShowTestWindow(bool* p_open)
             if (ImGui::IsItemActive()) has_focus = 3;
             ImGui::PopAllowKeyboardFocus();
 
+            if (has_focus)
+                ImGui::Text("Item with focus: %d", has_focus);
+            else
+                ImGui::Text("Item with focus: <none>");
+
             // Use >= 0 parameter to SetKeyboardFocusHere() to focus an upcoming item
             static float f3[3] = { 0.0f, 0.0f, 0.0f };
             int focus_ahead = -1;
@@ -1763,14 +1768,26 @@ void ImGui::ShowTestWindow(bool* p_open)
             if (focus_ahead != -1) ImGui::SetKeyboardFocusHere(focus_ahead);
             ImGui::SliderFloat3("Float3", &f3[0], 0.0f, 1.0f);
 
-            if (has_focus)
+            ImGui::TextWrapped("NB: Cursor & selection are preserved when refocusing last used item in code.");
-                ImGui::Text("Item with focus: %d", has_focus);
-            else
-                ImGui::Text("Item with focus: <none>");
-            ImGui::TextWrapped("Cursor & selection are preserved when refocusing last used item in code.");
             ImGui::TreePop();
         }
 
+#if 0
+        if (ImGui::TreeNode("Remote Activation"))
+        {
+            static char label[256];
+            ImGui::InputText("Label", label, IM_ARRAYSIZE(label));
+            ImGui::PopID(); // We don't yet have an easy way compute ID at other levels of the ID stack so we pop it manually for now (e.g. we'd like something like GetID("../label"))
+            ImGuiID id = ImGui::GetID(label);
+            ImGui::PushID("Remote Activation");
+            if (ImGui::SmallButton("Activate"))
+                ImGui::ActivateItem(id);
+            ImGui::SameLine();
+            ImGui::Text("ID = 0x%08X", id);
+            ImGui::TreePop();
+        }
+#endif
+
         if (ImGui::TreeNode("Dragging"))
         {
             ImGui::TextWrapped("You can use ImGui::GetMouseDragDelta(0) to query for the dragged amount on any widget.");

imgui_internal.h

@@ -469,6 +469,7 @@ struct ImGuiContext
     ImGuiID                 NavInputId;                         // ~~ IsNavInputPressed(ImGuiNavInput_PadInput) ? NavId : 0, etc.
     ImGuiID                 NavJustTabbedId;                    // Just tabbed to this id.
     ImGuiID                 NavJustNavigatedId;                 // Just navigated to this id (result of a successfully MoveRequest)
+    ImGuiID                 NavNextActivateId;                  // Set by ActivateItem(), queued until next frame
     ImRect                  NavScoringRectScreen;               // Rectangle used for scoring, in screen space. Based of window->DC.NavRefRectRel[], modified for directional navigation scoring.
     ImGuiWindow*            NavWindowingTarget;
     float                   NavWindowingDisplayAlpha;
@@ -584,7 +585,7 @@ struct ImGuiContext
 
         NavWindow = NULL;
         NavId = NavActivateId = NavActivateDownId = NavInputId = 0;
-        NavJustTabbedId = NavJustNavigatedId = 0;
+        NavJustTabbedId = NavJustNavigatedId = NavNextActivateId = 0;
         NavScoringRectScreen = ImRect();
         NavWindowingTarget = NULL;
         NavWindowingDisplayAlpha = 0.0f;