DiagramControlContainer.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace XSDDigitalToXML
{
    class DiagramControlContainer : UserControl
    {
        private DiagramControl diagramControl;
        private VScrollBar vScrollBar;
        private HScrollBar hScrollBar;
        private Point virtualPoint = new Point(0, 0);
        private Size virtualSize = new Size(10, 10);
        private bool isDragging = false;
        private Point mouseDownPosition = new Point(0, 0);
        private int mouseDownHScroll = 0;
        private int mouseDownVScroll = 0;

        public DiagramControl DiagramControl { get { return this.diagramControl; } }

        public Point VirtualPoint
        {
            get { return this.virtualPoint; }
            set { this.virtualPoint = value; }
        }

        public Size VirtualSize
        {
            get { return this.virtualSize; }
            set { this.virtualSize = value; diagramControl_Resize(null, null); }
        }

        public DiagramControlContainer()
        {
            InitializeComponent();

            this.diagramControl.MouseWheel += new MouseEventHandler(diagramControl_MouseWheel);
        }

        private void InitializeComponent()
        {
            this.vScrollBar = new System.Windows.Forms.VScrollBar();
            this.hScrollBar = new System.Windows.Forms.HScrollBar();
            this.diagramControl = new XSDDigitalToXML.DiagramControl();
            this.SuspendLayout();
            // 
            // vScrollBar
            // 
            this.vScrollBar.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.vScrollBar.Location = new System.Drawing.Point(437, 0);
            this.vScrollBar.Name = "vScrollBar";
            this.vScrollBar.Size = new System.Drawing.Size(17, 348);
            this.vScrollBar.SmallChange = 5;
            this.vScrollBar.TabIndex = 0;
            this.vScrollBar.ValueChanged += new System.EventHandler(this.vScrollBar_ValueChanged);
            // 
            // hScrollBar
            // 
            this.hScrollBar.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.hScrollBar.Location = new System.Drawing.Point(0, 348);
            this.hScrollBar.Name = "hScrollBar";
            this.hScrollBar.Size = new System.Drawing.Size(437, 17);
            this.hScrollBar.SmallChange = 5;
            this.hScrollBar.TabIndex = 1;
            this.hScrollBar.ValueChanged += new System.EventHandler(this.vScrollBar_ValueChanged);
            // 
            // diagramControl
            // 
            this.diagramControl.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
                        | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.diagramControl.Location = new System.Drawing.Point(0, 0);
            this.diagramControl.Margin = new System.Windows.Forms.Padding(0);
            this.diagramControl.Name = "diagramControl";
            this.diagramControl.Size = new System.Drawing.Size(437, 348);
            this.diagramControl.TabIndex = 2;
            this.diagramControl.MouseDown += new System.Windows.Forms.MouseEventHandler(this.diagramControl_MouseDown);
            this.diagramControl.MouseMove += new System.Windows.Forms.MouseEventHandler(this.diagramControl_MouseMove);
            this.diagramControl.Resize += new System.EventHandler(this.diagramControl_Resize);
            this.diagramControl.MouseUp += new System.Windows.Forms.MouseEventHandler(this.diagramControl_MouseUp);
            // 
            // DiagramControlContainer
            // 
            this.Controls.Add(this.diagramControl);
            this.Controls.Add(this.hScrollBar);
            this.Controls.Add(this.vScrollBar);
            this.Name = "DiagramControlContainer";
            this.Size = new System.Drawing.Size(454, 365);
            this.ResumeLayout(false);

        }

        void diagramControl_MouseWheel(object sender, MouseEventArgs e)
        {
            if ((ModifierKeys & Keys.Control) != Keys.Control)
            {
                int scrollBarValue = this.vScrollBar.Value;
                scrollBarValue -= e.Delta;
                if (scrollBarValue > this.vScrollBar.Maximum - this.vScrollBar.LargeChange)
                    scrollBarValue = this.vScrollBar.Maximum - this.vScrollBar.LargeChange;
                if (scrollBarValue < this.vScrollBar.Minimum)
                    scrollBarValue = this.vScrollBar.Minimum;
                this.vScrollBar.Value = scrollBarValue;
            }
        }

        private void diagramControl_Resize(object sender, EventArgs e)
        {
            LayoutScrollBars();
        }

        public void Clear()
        {
            this.hScrollBar.Value = 0;
            this.vScrollBar.Value = 0;
            LayoutScrollBars();
        }

        public void LayoutScrollBars()
        {
            this.SuspendLayout();
            Size diagramControlNewSize = this.ClientSize;
            if (this.virtualSize.Width > this.diagramControl.ClientSize.Width)
            {
                this.hScrollBar.Minimum = 0;
                this.hScrollBar.Maximum = this.virtualSize.Width;
                this.hScrollBar.LargeChange = this.diagramControl.ClientSize.Width;
                diagramControlNewSize.Height -= this.hScrollBar.Height;
            }
            else
            {
                this.hScrollBar.Minimum = 0;
                this.hScrollBar.Maximum = 0;
            }

            if (this.virtualSize.Height > this.diagramControl.ClientSize.Height)
            {
                this.vScrollBar.Minimum = 0;
                this.vScrollBar.Maximum = this.virtualSize.Height;
                this.vScrollBar.LargeChange = this.diagramControl.ClientSize.Height;
                diagramControlNewSize.Width -= this.vScrollBar.Width;
            }
            else
            {
                this.vScrollBar.Minimum = 0;
                this.vScrollBar.Maximum = 0;
            }

            if (!Options.IsRunningOnMono)
            {
                Size hScrollBarSize = this.hScrollBar.Size;
                if (this.hScrollBar.Maximum > 0 && this.vScrollBar.Maximum == 0)
                    hScrollBarSize.Width = this.ClientSize.Width;
                else
                    hScrollBarSize.Width = this.ClientSize.Width - this.vScrollBar.Width;
                this.hScrollBar.Size = hScrollBarSize;

                Size vScrollBarSize = this.vScrollBar.Size;
                if (this.vScrollBar.Maximum > 0 && this.hScrollBar.Maximum == 0)
                    vScrollBarSize.Height = this.ClientSize.Height;
                else
                    vScrollBarSize.Height = this.ClientSize.Height - this.hScrollBar.Height;
                this.vScrollBar.Size = vScrollBarSize;
            }

            this.diagramControl.Size = diagramControlNewSize;
            this.diagramControl.Invalidate(this.diagramControl.ClientRectangle);
            this.ResumeLayout();
        }

        public void ScrollTo(Point point)
        {
            ScrollTo(point, false);
        }

        public void ScrollTo(Point point, bool center)
        {
            if (center)
            {
                point.X -= this.DiagramControl.ClientRectangle.Width / 2;
                point.Y -= this.DiagramControl.ClientRectangle.Height / 2;
            }

            if (point.X > this.hScrollBar.Maximum - this.hScrollBar.LargeChange)
                point.X = this.hScrollBar.Maximum - this.hScrollBar.LargeChange;
            if (point.X < this.hScrollBar.Minimum)
                point.X = this.hScrollBar.Minimum;
            if (point.Y > this.vScrollBar.Maximum - this.vScrollBar.LargeChange)
                point.Y = this.vScrollBar.Maximum - this.vScrollBar.LargeChange;
            if (point.Y < this.vScrollBar.Minimum)
                point.Y = this.vScrollBar.Minimum;

            this.hScrollBar.Value = point.X;
            this.vScrollBar.Value = point.Y;
        }

        private void vScrollBar_ValueChanged(object sender, EventArgs e)
        {
            this.virtualPoint = new Point(this.hScrollBar.Value, this.vScrollBar.Value);
            //System.Diagnostics.Trace.WriteLine("h: " + this.hScrollBar.Value + " (min: " + this.hScrollBar.Minimum + ", max: " + this.hScrollBar.Maximum + "), v: " + this.vScrollBar.Value + " (min: " + this.vScrollBar.Minimum + ", max: " + this.vScrollBar.Maximum + ")");
            this.diagramControl.Invalidate(this.diagramControl.ClientRectangle);
        }

        private void diagramControl_MouseMove(object sender, MouseEventArgs e)
        {
            if (this.isDragging)
            {
                int hValue = this.mouseDownHScroll + (this.mouseDownPosition.X - Cursor.Position.X);
                if (hValue > this.hScrollBar.Minimum && hValue < this.hScrollBar.Maximum - this.hScrollBar.LargeChange)
                    this.hScrollBar.Value = hValue;

                int vValue = this.mouseDownVScroll + (this.mouseDownPosition.Y - Cursor.Position.Y);
                if (vValue > this.vScrollBar.Minimum && vValue < this.vScrollBar.Maximum - this.vScrollBar.LargeChange)
                    this.vScrollBar.Value = vValue;
            }
        }

        private void diagramControl_MouseDown(object sender, MouseEventArgs e)
        {
            if (!this.isDragging)
            {
                this.mouseDownPosition = Cursor.Position;
                this.mouseDownHScroll = this.hScrollBar.Value;
                this.mouseDownVScroll = this.vScrollBar.Value;
                this.isDragging = true;
            }
        }

        private void diagramControl_MouseUp(object sender, MouseEventArgs e)
        {
            this.isDragging = false;
        }
    }
}