Function ShowDatePicker

src-core/imgui/implot/implot.cpp:5437–5646

}

bool ShowDatePicker(const char* id, int* level, ImPlotTime* t, const ImPlotTime* t1, const ImPlotTime* t2) {

    ImGui::PushID(id);
    ImGui::BeginGroup();

    ImGuiStyle& style = ImGui::GetStyle();
    ImVec4 col_txt    = style.Colors[ImGuiCol_Text];
    ImVec4 col_dis    = style.Colors[ImGuiCol_TextDisabled];
    ImVec4 col_btn    = style.Colors[ImGuiCol_Button];
    ImGui::PushStyleColor(ImGuiCol_Button, ImVec4(0,0,0,0));
    ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0,0));

    const float ht    = ImGui::GetFrameHeight();
    ImVec2 cell_size(ht*1.25f,ht);
    char buff[32];
    bool clk = false;
    tm& Tm = GImPlot->Tm;

    const int min_yr = 1970;
    const int max_yr = 2999;

    // t1 parts
    int t1_mo = 0; int t1_md = 0; int t1_yr = 0;
    if (t1 != nullptr) {
        GetTime(*t1,&Tm);
        t1_mo = Tm.tm_mon;
        t1_md = Tm.tm_mday;
        t1_yr = Tm.tm_year + 1900;
    }

     // t2 parts
    int t2_mo = 0; int t2_md = 0; int t2_yr = 0;
    if (t2 != nullptr) {
        GetTime(*t2,&Tm);
        t2_mo = Tm.tm_mon;
        t2_md = Tm.tm_mday;
        t2_yr = Tm.tm_year + 1900;
    }

    // day widget
    if (*level == 0) {
        *t = FloorTime(*t, ImPlotTimeUnit_Day);
        GetTime(*t, &Tm);
        const int this_year = Tm.tm_year + 1900;
        const int last_year = this_year - 1;
        const int next_year = this_year + 1;
        const int this_mon  = Tm.tm_mon;
        const int last_mon  = this_mon == 0 ? 11 : this_mon - 1;
        const int next_mon  = this_mon == 11 ? 0 : this_mon + 1;
        const int days_this_mo = GetDaysInMonth(this_year, this_mon);
        const int days_last_mo = GetDaysInMonth(this_mon == 0 ? last_year : this_year, last_mon);
        ImPlotTime t_first_mo = FloorTime(*t,ImPlotTimeUnit_Mo);
        GetTime(t_first_mo,&Tm);
        const int first_wd = Tm.tm_wday;
        // month year
        ImFormatString(buff, 32, "%s %d", MONTH_NAMES[this_mon], this_year);
        if (ImGui::Button(buff))
            *level = 1;