From cdea8ca94fffbbc32fabfd1b0f8789b125384486 Mon Sep 17 00:00:00 2001 From: omar Date: Sun, 6 Aug 2017 11:07:52 +0800 Subject: [PATCH] Demo: Comment about 'static' and some tweaks (#1267) --- imgui_demo.cpp | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/imgui_demo.cpp b/imgui_demo.cpp index f2d03396..b248a645 100644 --- a/imgui_demo.cpp +++ b/imgui_demo.cpp @@ -6,14 +6,18 @@ // Everything in this file will be stripped out by the linker if you don't call ImGui::ShowTestWindow(). // During development, you can call ImGui::ShowTestWindow() in your code to learn about various features of ImGui. Have it wired in a debug menu! // Removing this file from your project is hindering access to documentation for everyone in your team, likely leading you to poorer usage of the library. - // Note that you can #define IMGUI_DISABLE_TEST_WINDOWS in imconfig.h for the same effect. // If you want to link core ImGui in your public builds but not those test windows, #define IMGUI_DISABLE_TEST_WINDOWS in imconfig.h and those functions will be empty. // For any other case, if you have ImGui available you probably want this to be available for reference and execution. - // Thank you, // -Your beloved friend, imgui_demo.cpp (that you won't delete) +// Message to beginner C/C++ programmer about the meaning of 'static': in this demo code, we frequently we use 'static' variables inside functions. +// We do this as a way to gather code and data in the same place, make the demo code faster to read, faster to write, and smaller. A static variable persist across calls, +// so it is essentially like a global variable but declared inside the scope of the function. +// It also happens to be a convenient way of storing simple UI related information as long as your function doesn't need to be reentrant or used in threads. +// This may be a pattern you want to use in your code (simple is beautiful!), but most of the real data you would be editing is likely to be stored outside your function. + #if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS) #define _CRT_SECURE_NO_WARNINGS #endif @@ -538,9 +542,13 @@ void ImGui::ShowTestWindow(bool* p_open) ImGui::TreePop(); } - static bool a=false; - if (ImGui::Button("Button")) { printf("Clicked\n"); a ^= 1; } - if (a) + static bool my_toggle = false; + if (ImGui::Button("Button")) + { + printf("Clicked\n"); + my_toggle = !my_toggle; + } + if (my_toggle) { ImGui::SameLine(); ImGui::Text("Thanks for clicking me!");