From db0338a1f2b1f0b05f910888222cacd17fec26e8 Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 9 Jun 2021 19:15:56 +0200
Subject: [PATCH] Nav, Drag and Drop, Docking: fixed two issues leading nav
 result to conflict with moving a window. (#4211, #3025)

---
 imgui.cpp         | 22 ++++++++++++++++------
 imgui_internal.h  |  1 +
 imgui_widgets.cpp |  2 ++
 3 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/imgui.cpp b/imgui.cpp
index c08daeb2..6bd0adc2 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -3582,8 +3582,9 @@ void ImGui::StartMouseMovingWindow(ImGuiWindow* window)
     FocusWindow(window);
     SetActiveID(window->MoveId, window);
     g.NavDisableHighlight = true;
-    g.ActiveIdNoClearOnFocusLoss = true;
     g.ActiveIdClickOffset = g.IO.MouseClickedPos[0] - window->RootWindowDockTree->Pos;
+    g.ActiveIdNoClearOnFocusLoss = true;
+    SetActiveIdUsingNavAndKeys();
 
     bool can_move_window = true;
     if ((window->Flags & ImGuiWindowFlags_NoMove) || (window->RootWindowDockTree->Flags & ImGuiWindowFlags_NoMove))
@@ -3665,8 +3666,8 @@ void ImGui::UpdateMouseMovingWindowNewFrame()
             // Clear the NoInput window flag set by the Viewport system
             moving_window->Viewport->Flags &= ~ImGuiViewportFlags_NoInputs; // FIXME-VIEWPORT: Test engine managed to crash here because Viewport was NULL.
 
-            ClearActiveID();
             g.MovingWindow = NULL;
+            ClearActiveID();
         }
     }
     else
@@ -5213,6 +5214,16 @@ void ImGui::SetItemUsingMouseWheel()
         g.ActiveIdUsingMouseWheel = true;
 }
 
+void ImGui::SetActiveIdUsingNavAndKeys()
+{
+    ImGuiContext& g = *GImGui;
+    IM_ASSERT(g.ActiveId != 0);
+    g.ActiveIdUsingNavDirMask = ~(ImU32)0;
+    g.ActiveIdUsingNavInputMask = ~(ImU32)0;
+    g.ActiveIdUsingKeyInputMask = ~(ImU64)0;
+    NavMoveRequestCancel();
+}
+
 ImVec2 ImGui::GetItemRectMin()
 {
     ImGuiWindow* window = GetCurrentWindowRead();
@@ -10571,10 +10582,8 @@ bool ImGui::BeginDragDropSource(ImGuiDragDropFlags flags)
         source_parent_id = window->IDStack.back();
         source_drag_active = IsMouseDragging(mouse_button);
 
-        // Disable navigation and key inputs while dragging
-        g.ActiveIdUsingNavDirMask = ~(ImU32)0;
-        g.ActiveIdUsingNavInputMask = ~(ImU32)0;
-        g.ActiveIdUsingKeyInputMask = ~(ImU64)0;
+        // Disable navigation and key inputs while dragging + cancel existing request if any
+        SetActiveIdUsingNavAndKeys();
     }
     else
     {
@@ -16524,6 +16533,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
         Indent();
         Text("ActiveId: 0x%08X/0x%08X (%.2f sec), AllowOverlap: %d, Source: %s", g.ActiveId, g.ActiveIdPreviousFrame, g.ActiveIdTimer, g.ActiveIdAllowOverlap, input_source_names[g.ActiveIdSource]);
         Text("ActiveIdWindow: '%s'", g.ActiveIdWindow ? g.ActiveIdWindow->Name : "NULL");
+        Text("ActiveIdUsing: Wheel: %d, NavDirMask: %X, NavInputMask: %X, KeyInputMask: %X", g.ActiveIdUsingMouseWheel, g.ActiveIdUsingNavDirMask, g.ActiveIdUsingNavInputMask, g.ActiveIdUsingKeyInputMask);
         Text("HoveredId: 0x%08X/0x%08X (%.2f sec), AllowOverlap: %d", g.HoveredId, g.HoveredIdPreviousFrame, g.HoveredIdTimer, g.HoveredIdAllowOverlap); // Data is "in-flight" so depending on when the Metrics window is called we may see current frame information or not
         Text("DragDrop: %d, SourceId = 0x%08X, Payload \"%s\" (%d bytes)", g.DragDropActive, g.DragDropPayload.SourceId, g.DragDropPayload.DataType, g.DragDropPayload.DataSize);
         Unindent();
diff --git a/imgui_internal.h b/imgui_internal.h
index b4177ddf..b7b28bd6 100644
--- a/imgui_internal.h
+++ b/imgui_internal.h
@@ -2665,6 +2665,7 @@ namespace ImGui
     // Inputs
     // FIXME: Eventually we should aim to move e.g. IsActiveIdUsingKey() into IsKeyXXX functions.
     IMGUI_API void          SetItemUsingMouseWheel();
+    IMGUI_API void          SetActiveIdUsingNavAndKeys();
     inline bool             IsActiveIdUsingNavDir(ImGuiDir dir)                         { ImGuiContext& g = *GImGui; return (g.ActiveIdUsingNavDirMask & (1 << dir)) != 0; }
     inline bool             IsActiveIdUsingNavInput(ImGuiNavInput input)                { ImGuiContext& g = *GImGui; return (g.ActiveIdUsingNavInputMask & (1 << input)) != 0; }
     inline bool             IsActiveIdUsingKey(ImGuiKey key)                            { ImGuiContext& g = *GImGui; IM_ASSERT(key < 64); return (g.ActiveIdUsingKeyInputMask & ((ImU64)1 << key)) != 0; }
diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index 61e48883..ef0cd287 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp
@@ -7987,11 +7987,13 @@ bool    ImGui::TabItemEx(ImGuiTabBar* tab_bar, const char* label, bool* p_open,
             if (undocking_tab)
             {
                 // Undock
+                // FIXME: refactor to share more code with e.g. StartMouseMovingWindow
                 DockContextQueueUndockWindow(&g, docked_window);
                 g.MovingWindow = docked_window;
                 SetActiveID(g.MovingWindow->MoveId, g.MovingWindow);
                 g.ActiveIdClickOffset -= g.MovingWindow->Pos - bb.Min;
                 g.ActiveIdNoClearOnFocusLoss = true;
+                SetActiveIdUsingNavAndKeys();
             }
         }
     }