Embedding a window as a ChildWindow

[phed]

Is it possible to embed a window into another one?
I was happy to find that I could use child windows to create paned layouts, and that you could build on these windows with ::BeginChild(id) with the same ID later.
However, is there a way to embed a window that has been created with ::Begin(id) into a child-window in a similar manner? Reason is that I want to re-use code that creates regular windows..

Not very important, but I feel like there's a trick I am missing.

[ocornut]

The trick is to call BeginChild instead of Begin...?

[phed]

As I said it is a minor thing. But the obvious thing would be to signal to the embedded window that it should call BeginChild instead of Child. The trick I was looking for is having the first instance, the embedder, making this decision. Anyway, I am now settling on just adding a boolean to the arguments of the window-functions , like hexeditor(id, ..., show, child) now.

[ocornut]

Yes that’s how I would be doing it. The embedder can’t signal it to the embedded via a generic manner. Not sure what exactly is your usage context, this is the kind of thing that a Docking system (#351) would take care of (essentially redirecting the output of a window) - but it that would be tailored for the specific purpose of docking.

[ocornut]

@phed: are you happy with this, can we close the thread or it is still an open topic for you?
Thanks.

[phed]

Oh sorry, I was happy with the answer. Just close.
For completeness sake, I'll include the code that I am using project-wide to handle all sorts of window-cases. I do not really suggest anyone use this, but I am happy with it.

namespace ImGuiExt {
    enum ImGuiExtWindowMode {
        ImGuiExtWindowMode_Invalid,
        ImGuiExtWindowMode_Window,
        ImGuiExtWindowMode_ChildWindow,
        ImGuiExtWindowMode_Flat,
        ImGuiExtWindowMode_Fullscreen,
    };

    ImGuiExtWindowMode last_mode = ImGuiExtWindowMode_Invalid;

    bool Begin(const char* name, ImGuiExtWindowMode mode, bool *open = 0) {
        bool res = false;
        //const ImGuiWindowFlags background_flags = ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoBringToFrontOnFocus | ImGuiWindowFlags_NoResize;
        const ImGuiWindowFlags fullscreen_flags = ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_Modal;

        assert(last_mode == ImGuiExtWindowMode_Invalid);
        switch (mode) {
        case ImGuiExtWindowMode_Window:
            res = ImGui::Begin(name, open);
            break;
        case ImGuiExtWindowMode_ChildWindow:
            res = ImGui::BeginChild(name);
            break;
        case ImGuiExtWindowMode_Flat:
            break;
        case ImGuiExtWindowMode_Fullscreen:
            ImGui::SetNextWindowSize(ImGui::GetIO().DisplaySize);
            ImGui::SetNextWindowPos(ImVec2(0, 0));
            res = ImGui::Begin(name, 0, fullscreen_flags);
            break;
        default:
            assert(0);
        }
        last_mode = mode;
        return res;
    }
    void End() {
        switch (last_mode) {
        case ImGuiExtWindowMode_Fullscreen:
        case ImGuiExtWindowMode_Window:
            ImGui::End();
            break;
        case ImGuiExtWindowMode_ChildWindow:
            ImGui::EndChild();
            break;
        case ImGuiExtWindowMode_Flat:
            break;
        default:
            assert(0);
        }
        last_mode = ImGuiExtWindowMode_Invalid;
    }
}