Project Management

Use it wherever work is planned against dates – a product launch, a fit-out, a release – to answer what a planner asks of a plan (when does it finish, what is late, which tasks have no slack) and to let them change it by dragging.

The plan

A plan is two lists that belong to the application: Tasks, a flat list of ProjectTask objects in which a subtask names its summary through ProjectTask.ParentId, and Links, the TaskLink dependencies between them – the shape a database table or a spreadsheet already has. An ObservableCollection is watched, and so is every task and link in it: change a property and the chart schedules again and redraws.

Scheduling

Dates are worked out by the critical-path method on working days – the days WorkingWeek names, less the Holidays, from ProjectStart. A task starts on its planned ProjectTask.Start or as soon as its links allow, whichever is later, and a summary spans its subtasks. The result is in Schedule, and ScheduleChanged says when it has been worked out again. Bad data never stops the chart: a link to a missing task, or a loop, is left out and reported in ProjectSchedule.Problems, and everything else is drawn.

The two panes

The task list on the left shows the outline and the Columns you choose; the timeline on the right shows a bar for each task, a diamond for each milestone and a bracket for each summary, at the scale Zoom sets. The panes scroll up and down together; the splitter between them sets GridWidth.

Editing

Drag a bar to move the task, its right-hand end to change its length, or the triangle under it to set its progress; drag from the dot past its end to another row to link the two finish-to-start. Press F2 to type into the current cell – name, start, days, % done or predecessors (outline numbers such as 2, 3SS+1). Every edit is offered first through TaskChanging or LinksChanging, which can cancel it, then made to the task or link object itself and announced by TaskChanged or LinksChanged. IsReadOnly allows looking only.

The keyboard

One plan, three views

Give the same lists to a PertChart and a TaskBoard and the three agree: they schedule the same objects with the same arithmetic, so a bar dragged here or a card moved on the board is seen by all of them.

Appearance

The chart draws itself and has no template. Control.Background, Control.Foreground and the font apply as usual; the bars, links and calendar have brush properties (BarBrush, CriticalBrush and the rest) whose defaults read on light and dark backgrounds alike, and in Windows high contrast the system colours replace them all. The chart always runs left to right, as a calendar does. ExportImage and Print draw the whole plan.

A window that plans a website relaunch, built in code so that it stands on its own; in XAML the lists are bound, as in <pm:GanttChart Tasks="{Binding Tasks}" Links="{Binding Links}" Zoom="Week" /> with xmlns:pm="clr-namespace:Binarymission.WPF.Controls.ProjectManagement;assembly=Binarymission.WPF.Controls.ProjectManagement".

using System;
using System.Collections.ObjectModel;
using System.Windows;
using Binarymission.WPF.Controls.ProjectManagement;

public sealed class PlanWindow : Window
{
    public PlanWindow()
    {
        var tasks = new ObservableCollection<ProjectTask>
        {
            new ProjectTask("design", "Design"),                     // a summary: it has subtasks
            new ProjectTask("wire", "Wireframes", 5)    { ParentId = "design", Assignee = "Priya Shah", Progress = 100 },
            new ProjectTask("look", "Visual design", 8) { ParentId = "design", Assignee = "Tom Ellis", Progress = 40 },
            new ProjectTask("build", "Build"),
            new ProjectTask("web", "Front end", 10)     { ParentId = "build", Assignee = "Ana Ruiz" },
            new ProjectTask("api", "Orders API", 12)    { ParentId = "build", Assignee = "Sam Okafor" },
            new ProjectTask("live", "Go live", 0),                    // no length: a milestone
        };
        var links = new ObservableCollection<TaskLink>
        {
            new TaskLink("wire", "look"),                             // finish-to-start
            new TaskLink("look", "web", TaskLinkType.StartToStart, 3), // 3 working days after it starts
            new TaskLink("wire", "api"),
            new TaskLink("web", "live"),
            new TaskLink("api", "live"),
        };

        var gantt = new GanttChart
        {
            Tasks = tasks,
            Links = links,
            ProjectStart = new DateTime(2026, 11, 2),
            Columns = GanttColumns.Default | GanttColumns.Assignee,
        };
        gantt.Holidays.Add(new DateTime(2026, 12, 25));

        // A finished task stays where it is, whichever way the reader tries to move it.
        gantt.TaskChanging += (sender, e) =>
            e.Cancel = e.Task.Progress >= 100 && (e.NewStart.HasValue || e.NewDuration.HasValue);
        gantt.ScheduleChanged += (sender, e) =>
            Title = "Website relaunch - finishes " + gantt.Schedule.ProjectFinish.ToString("d MMM yyyy");

        Content = gantt;
        Loaded += (sender, e) => gantt.ZoomToFit();
    }
}