#region License Information (GPL v3) /* ShareX - A program that allows you to take screenshots and share any file type Copyright (c) 2007-2024 ShareX Team This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. Optionally you can also view the license at . */ #endregion License Information (GPL v3) using System; using System.Drawing; using System.Windows.Forms; namespace ShareX.HelpersLib { public class Canvas : UserControl { public delegate void DrawEventHandler(Graphics g); public event DrawEventHandler Draw; public int Interval { get; set; } private Timer timer; private bool needPaint; public Canvas() { Interval = 100; SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.OptimizedDoubleBuffer, true); } public void Start() { if (timer == null || !timer.Enabled) { Stop(); timer = new Timer(); timer.Interval = Interval; timer.Tick += timer_Tick; timer.Start(); } } public void Start(int interval) { Interval = interval; Start(); } public void Stop() { if (timer != null) { timer.Stop(); timer.Dispose(); } } protected override void Dispose(bool disposing) { Stop(); base.Dispose(disposing); } private void timer_Tick(object sender, EventArgs e) { needPaint = true; Invalidate(); } protected override void OnPaint(PaintEventArgs e) { if (needPaint) { OnDraw(e.Graphics); needPaint = false; } } protected void OnDraw(Graphics g) { Draw?.Invoke(g); } } }