Examples: SDL: Avoid testing for SDL_GetKeyboardFocus() on Android and iOS (like Emscripten). (#421)

examples/imgui_impl_sdl.cpp

@@ -16,6 +16,7 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2018-12-21: Inputs: Workaround for Android/iOS which don't seem to handle focus related calls.
 //  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
 //  2018-11-14: Changed the signature of ImGui_ImplSDL2_ProcessEvent() to take a 'const SDL_Event*'.
 //  2018-08-01: Inputs: Workaround for Emscripten which doesn't seem to handle focus related calls.
@@ -42,8 +43,11 @@
 // (the multi-viewports feature requires SDL features supported from SDL 2.0.5+)
 #include <SDL.h>
 #include <SDL_syswm.h>
+#if defined(__APPLE__)
+#include "TargetConditionals.h"
+#endif
 
-#define SDL_HAS_CAPTURE_MOUSE               SDL_VERSION_ATLEAST(2,0,4)
+#define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    SDL_VERSION_ATLEAST(2,0,4)
 #define SDL_HAS_VULKAN                      SDL_VERSION_ATLEAST(2,0,6)
 #define SDL_HAS_MOUSE_FOCUS_CLICKTHROUGH    SDL_VERSION_ATLEAST(2,0,5)
 #if !SDL_HAS_VULKAN
@@ -182,9 +186,9 @@ bool ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context)
 
 bool ImGui_ImplSDL2_InitForVulkan(SDL_Window* window)
 {
-    #if !SDL_HAS_VULKAN
+#if !SDL_HAS_VULKAN
     IM_ASSERT(0 && "Unsupported");
-    #endif
+#endif
     return ImGui_ImplSDL2_Init(window);
 }
 
@@ -220,7 +224,7 @@ static void ImGui_ImplSDL2_UpdateMousePosAndButtons()
     io.MouseDown[2] = g_MousePressed[2] || (mouse_buttons & SDL_BUTTON(SDL_BUTTON_MIDDLE)) != 0;
     g_MousePressed[0] = g_MousePressed[1] = g_MousePressed[2] = false;
 
-#if SDL_HAS_CAPTURE_MOUSE && !defined(__EMSCRIPTEN__)
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE && !defined(__EMSCRIPTEN__) && !defined(__ANDROID__) && !(defined(__APPLE__) && TARGET_OS_IOS))
     SDL_Window* focused_window = SDL_GetKeyboardFocus();
     if (g_Window == focused_window)
     {