imgui_stdlib.cpp

// Code from IMGUI for support of std::string
// dear imgui: wrappers for C++ standard library (STL) types (std::string, etc.)
// This is also an example of how you may wrap your own similar types.
 
// Compatibility:
// - std::string support is only guaranteed to work from C++11.
//   If you try to use it pre-C++11, please share your findings (w/ info about compiler/architecture)
 
// Changelog:
// - v0.10: Initial version. Added InputText() / InputTextMultiline() calls with std::string
 
#include "imgui_stdlib.h"
#include "imgui.h"
 
struct InputTextCallback_UserData
{
    std::string *Str;
    ImGuiInputTextCallback ChainCallback;
    void *ChainCallbackUserData;
};
 
static int InputTextCallback(ImGuiInputTextCallbackData *data)
{
    InputTextCallback_UserData *user_data = (InputTextCallback_UserData *)data->UserData;
    if (data->EventFlag == ImGuiInputTextFlags_CallbackResize)
    {
        // Resize string callback
        // If for some reason we refuse the new length (BufTextLen) and/or capacity (BufSize) we need to set them back
        // to what we want.
        std::string *str = user_data->Str;
        IM_ASSERT(data->Buf == str->c_str());
        str->resize(data->BufTextLen);
        data->Buf = (char *)str->c_str();
    }
    else if (user_data->ChainCallback)
    {
        // Forward to user callback, if any
        data->UserData = user_data->ChainCallbackUserData;
        return user_data->ChainCallback(data);
    }
    return 0;
}
 
bool ImGui::InputText(const char *label, std::string *str, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback,
                      void *user_data)
{
    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
    flags |= ImGuiInputTextFlags_CallbackResize;
 
    InputTextCallback_UserData cb_user_data;
    cb_user_data.Str = str;
    cb_user_data.ChainCallback = callback;
    cb_user_data.ChainCallbackUserData = user_data;
    return InputText(label, (char *)str->c_str(), str->capacity() + 1, flags, InputTextCallback, &cb_user_data);
}
 
bool ImGui::InputTextMultiline(const char *label, std::string *str, const ImVec2 &size, ImGuiInputTextFlags flags,
                               ImGuiInputTextCallback callback, void *user_data)
{
    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
    flags |= ImGuiInputTextFlags_CallbackResize;
 
    InputTextCallback_UserData cb_user_data;
    cb_user_data.Str = str;
    cb_user_data.ChainCallback = callback;
    cb_user_data.ChainCallbackUserData = user_data;
    return InputTextMultiline(label, (char *)str->c_str(), str->capacity() + 1, size, flags, InputTextCallback,
                              &cb_user_data);
}
 
bool ImGui::InputTextWithHint(const char *label, const char *hint, std::string *str, ImGuiInputTextFlags flags,
                              ImGuiInputTextCallback callback, void *user_data)
{
    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
    flags |= ImGuiInputTextFlags_CallbackResize;
 
    InputTextCallback_UserData cb_user_data;
    cb_user_data.Str = str;
    cb_user_data.ChainCallback = callback;
    cb_user_data.ChainCallbackUserData = user_data;
    return InputTextWithHint(label, hint, (char *)str->c_str(), str->capacity() + 1, flags, InputTextCallback,
                             &cb_user_data);
}