Example of using custom tab art with wxAUI

aui-tabart.cpp

#include <wx/app.h>
#include <wx/dc.h>
#include <wx/frame.h>
#include <wx/panel.h>
#include <wx/sizer.h>
#include <wx/textctrl.h>

#include <wx/aui/aui.h>

class TestDockArt : public wxAuiDefaultDockArt {
public:
    void DrawCaption(wxDC& dc,
                     wxWindow* window,
                     const wxString& text,
                     const wxRect& rect,
                     wxAuiPaneInfo& pane)
    {
        dc.SetBrush(*wxBLUE);
        dc.DrawRectangle(rect);
        dc.SetTextForeground(*wxYELLOW);
        dc.DrawText(text, rect.x + window->FromDIP(5), rect.y);
    }
};

class TestTabArt : public wxAuiGenericTabArt
{
public:
    wxAuiTabArt* Clone() override
    {
        return new TestTabArt{*this};
    }

    void
    DrawBackground(wxDC& dc,
                   wxWindow* WXUNUSED(wnd),
                   const wxRect& rect) override
    {
        dc.SetBrush(*wxBLACK_BRUSH);
        dc.DrawRectangle(rect);
    }

    void
    DrawTab(wxDC& dc,
            wxWindow* wnd,
            const wxAuiNotebookPage& pane,
            const wxRect& inRect,
            int closeButtonState,
            wxRect* outTabRect,
            wxRect* WXUNUSED(outButtonRect),
            int* xExtent) override
    {
        const wxSize tabSize = GetTabSize(dc, wnd, pane.caption, pane.bitmap,
                                          pane.active, closeButtonState,
                                          xExtent);

        *outTabRect = wxRect(inRect.GetPosition(), tabSize);

        // To draw a semi-rounded (on top only) rectangle, make it much higher
        // than necessary, so that the bottom round corners are chopped off.
        wxRect rect = *outTabRect;
        rect.height *= 2;

        dc.SetBrush(pane.active ? *wxBLUE_BRUSH : *wxTRANSPARENT_BRUSH);
        dc.DrawRoundedRectangle(rect, wnd->FromDIP(8));

        rect.height /= 2;

        // Use some horizontal padding.
        rect.Deflate(wnd->FromDIP(5), 0);

        // Draw the bitmap, if any.
        if ( pane.bitmap.IsOk() )
        {
            const auto& bitmap = pane.bitmap.GetBitmapFor(wnd);
            dc.DrawBitmap(bitmap,
                          rect.x,
                          rect.y + (rect.height - bitmap.GetLogicalHeight()) / 2,
                          true /* use mask */);

            rect.Deflate(bitmap.GetLogicalWidth() + wnd->FromDIP(5), 0);
        }

        // Draw the text.
        dc.SetTextForeground(*wxWHITE);
        dc.SetFont(pane.active ? m_selectedFont : m_normalFont);
        dc.DrawLabel(pane.caption, rect, wxALIGN_CENTER_VERTICAL);

        // Finally, draw the close button.
        if ( closeButtonState != wxAUI_BUTTON_STATE_HIDDEN )
        {
            const wxBitmapBundle bb(pane.active ? m_activeCloseBmp
                                                : m_disabledCloseBmp);

            const wxBitmap bitmap = bb.GetBitmapFor(wnd);

            rect.x = inRect.x + tabSize.x - bitmap.GetLogicalWidth() - wnd->FromDIP(5);
            rect.width = bitmap.GetLogicalWidth();

            // TODO: account for button state.
            dc.DrawBitmap(bitmap,
                          rect.x,
                          rect.y + (rect.height - bitmap.GetLogicalHeight()) / 2,
                          true /* use mask */);
        }
    }

    wxSize
    GetTabSize(wxDC& dc,
               wxWindow* wnd,
               const wxString& caption,
               const wxBitmapBundle& bitmap,
               bool WXUNUSED(active),
               int closeButtonState,
               int* xExtent) override
    {
        dc.SetFont(m_measuringFont);
        wxSize size = dc.GetTextExtent(caption);

        // Account for the close button.
        if ( closeButtonState != wxAUI_BUTTON_STATE_HIDDEN )
        {
            size.x += m_activeCloseBmp.GetBitmapFor(wnd).GetLogicalWidth();

            size.x += wnd->FromDIP(10);
        }

        // Account for the bitmap, if any.
        if ( bitmap.IsOk() )
        {
            const wxSize bitmapSize = bitmap.GetPreferredLogicalSizeFor(wnd);

            size.x += bitmapSize.x;
            size.x += wnd->FromDIP(10);

            if ( bitmapSize.y > size.y )
                size.y = bitmapSize.y;
        }

        // Add some padding.
        size += wnd->FromDIP(wxSize(20, 8));

        *xExtent = size.x;

        return size;
    }
};

class TestPanel : public wxPanel {
public:
    explicit TestPanel(wxWindow* parent) : wxPanel(parent, wxID_ANY) {
        m_manager.SetManagedWindow(this);

        m_manager.SetArtProvider(new TestDockArt);

        auto nb = new wxAuiNotebook(this);
        nb->AddPage(new wxTextCtrl(nb, wxID_ANY, "Welcome to the first page"), "First");
        nb->AddPage(new wxTextCtrl(nb, wxID_ANY, "And another one"), "Second");
        nb->AddPage(new wxTextCtrl(nb, wxID_ANY, "Last page, promised"), "Last");
        nb->SetArtProvider(new TestTabArt);

        m_manager.AddPane(nb, wxAuiPaneInfo().CenterPane().PaneBorder(false));
        m_manager.AddPane(new wxTextCtrl(this, wxID_ANY, "Left pane"), wxAuiPaneInfo().Left().Layer(1).MinSize(FromDIP(wxSize(200, 100))).Caption("Left pane").CloseButton());
        m_manager.AddPane(new wxTextCtrl(this, wxID_ANY, "Bottom pane"), wxAuiPaneInfo().Bottom().Layer(2).MinSize(FromDIP(wxSize(200, 100))).Caption("Bottom pane").MaximizeButton());
        m_manager.Update();
    }

private:
    wxAuiManager m_manager;
};

class TestApp : public wxApp {
public:
    bool OnInit() override {
        auto f = new wxFrame(nullptr, wxID_ANY, "Window containing AUI panel");
        auto t = new wxTextCtrl(f, wxID_ANY, "Just a text", wxDefaultPosition, wxDefaultSize, wxTE_MULTILINE);
        auto p = new TestPanel(f);
        auto s = new wxBoxSizer(wxHORIZONTAL);
        s->Add(t, wxSizerFlags().Expand());
        s->Add(p, wxSizerFlags(1).Expand());
        f->SetSizer(s);
        f->SetClientSize(f->FromDIP(wxSize(800, 600)));

        f->Show();
        return true;
    }
};

wxIMPLEMENT_APP(TestApp);