SourceCode/PROMS/TablePicker/TablePicker.cs

using System.Drawing;
using System.Windows.Forms;

namespace Accentra.Controls
{
	/// <summary>
	/// A FrontPage style table dimensions picker.
	/// </summary>
	public class TablePicker : System.Windows.Forms.Form
	{
		public TablePicker()
		{
			// Activates double buffering
			SetStyle(ControlStyles.UserPaint, true);
			SetStyle(ControlStyles.AllPaintingInWmPaint, true);
			SetStyle(ControlStyles.DoubleBuffer, true);

			//
			// Required for Windows Form Designer support
			//
			InitializeComponent();
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			this.SuspendLayout();
			// 
			// TablePicker
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(6, 15);
			this.BackColor = System.Drawing.Color.LightYellow;
			this.ClientSize = new System.Drawing.Size(304, 256);
			this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
			this.Name = "TablePicker";
			this.ShowInTaskbar = false;
			this.StartPosition = System.Windows.Forms.FormStartPosition.Manual;
			this.Text = "TablePicker";
			this.Deactivate += new System.EventHandler(this.TablePicker_Deactivate);
			this.Paint += new System.Windows.Forms.PaintEventHandler(this.TablePicker_Paint);
			this.MouseEnter += new System.EventHandler(this.TablePicker_MouseEnter);
			this.Click += new System.EventHandler(this.TablePicker_Click);
			this.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.TablePicker_KeyPress);
			this.MouseLeave += new System.EventHandler(this.TablePicker_MouseLeave);
			this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.TablePicker_MouseMove);
			this.ResumeLayout(false);

		}
		#endregion

		private readonly Brush BlackBrush = System.Drawing.Brushes.Black;
		private readonly Brush WhiteBrush = System.Drawing.Brushes.White;

		private readonly Brush Jbrush = System.Drawing.Brushes.LightBlue; 

		private readonly Pen BorderPen = new Pen(SystemColors.ControlDark);
		private readonly Pen BluePen = new Pen(Color.SlateGray, 1);

		private string DispText = "Esc to Cancel";	// Display text
		private readonly int DispHeight = 40;		// Display ("Table 1x1", "Cancel")
		private readonly Font DispFont = new Font("Tahoma", 8.25F);
		private readonly int SquareX = 20;			// Width of squares 
		private readonly int SquareY = 20;			// Height of squares
		private int SquareQX = 3;			// Number of visible squares (X)
		private int SquareQY = 3;			// Number of visible squares (Y)
		private int SelQX = 1;				// Number of selected squares (x)
		private int SelQY = 1;				// Number of selected squares (y)

        public int MaxRows { get; set; } = -1;

        public int MaxCols { get; set; } = -1;

        /// <summary>
        /// Returns the number of columns, or the horizontal / X count,
        /// of the selection.
        /// </summary>
        public int SelectedColumns => SelQX;

        /// <summary>
        /// Returns the number of rows, or the vertical / Y count, 
        /// of the selection.
        /// </summary>
        public int SelectedRows => SelQY;

        private void TablePicker_Paint(object sender, System.Windows.Forms.PaintEventArgs e) {
			Graphics g = e.Graphics;

			// First, increment the number of visible squares if the 
			// number of selected squares is equal to or greater than the
			// number of visible squares.
			if (SelQX > SquareQX - 1) SquareQX = SelQX + 1;
			if (SelQY > SquareQY - 1) SquareQY = SelQY + 1;

			if (SquareQX < 7) SquareQX = 7;
			if (SquareQY < 5) SquareQY = 5;

			if (MaxRows > 0 && SquareQY > MaxRows) SquareQY = MaxRows;
			if (MaxCols > 0 && SquareQX > MaxCols) SquareQX = MaxCols;

			// Second, expand the dimensions of this form according to the 
			// number of visible squares.
			this.Width = (SquareX * (SquareQX)) + 5;
			this.Height = (SquareY * (SquareQY)) + 6 + DispHeight;

			// Draw an outer rectangle for the border.
			g.DrawRectangle(BorderPen, 0, 0, this.Width - 1, this.Height - 1);
	
			// Draw the text to describe the selection. Note that since
			// the text is left-justified, only the Y (vertical) position
			// is calculated.
			int dispY = ((SquareY - 1) * SquareQY) + SquareQY + 4;
			DispText = $"{SelQY} Row{((SelQY > 1) ? "s" : "")}  {SelQX} Column{((SelQX > 1) ? "s" : "")}\nEsc to Cancel";
			g.DrawString(DispText, DispFont, BlackBrush, 3, dispY + 2); 

			// Draw each of the squares and fill with the default color.
			for (int x=0; x<SquareQX; x++) {
				for (int y=0; y<SquareQY; y++) {
					g.FillRectangle(WhiteBrush, (x*SquareX) + 3, (y*SquareY) + 3, SquareX - 2, SquareY - 2);
					g.DrawRectangle(BorderPen, (x*SquareX) + 3, (y*SquareY) + 3, SquareX - 2, SquareY - 2);
				}
			}
	
			// Go back and paint the squares with selection colors.
			for (int x=0; x<SelQX; x++) {
				for (int y=0; y<SelQY; y++) {
					g.FillRectangle(Jbrush, (x * SquareX) + 3, (y * SquareY) + 3, SquareX - 2, SquareY - 2);
					g.DrawRectangle(BluePen, (x * SquareX) + 3, (y * SquareY) + 3, SquareX - 2, SquareY - 2);
				}
			}
		}

		/// <summary>
		/// Detect termination. Hides form.
		/// </summary>
		private void TablePicker_Deactivate(object sender, System.EventArgs e) {

		}

		/// <summary>
		/// Detects mouse movement. Tracks table dimensions selection.
		/// </summary>
		private void TablePicker_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e) {
			int sqx = (e.X / SquareX) + 1;
			int sqy = (e.Y / SquareY) + 1;
			bool changed = false;
			if (sqx != SelQX) {
				changed = true;
				SelQX = sqx;
			}
			if (sqy != SelQY) {
				changed = true;
				SelQY = sqy;
			}

			// Ask Windows to call the Paint event again.
			if (changed) Invalidate();
		}

		/// <summary>
		/// Detects mouse sudden exit from the form to indicate 
		/// escaped (canceling) state.
		/// </summary>
		private void TablePicker_MouseLeave(object sender, System.EventArgs e) {
			if (this.DialogResult == DialogResult.None)
				this.DialogResult = DialogResult.Cancel;
		}

        /// <summary>
        /// Cancels the prior cancellation caused by MouseLeave.
        /// </summary>
        private void TablePicker_MouseEnter(object sender, System.EventArgs e) => this.Invalidate();

        /// <summary>
        /// Detects that the user made a selection by clicking.
        /// </summary>
        private void TablePicker_Click(object sender, System.EventArgs e) => this.DialogResult = DialogResult.OK;

        private void TablePicker_KeyPress(object sender, KeyPressEventArgs e)
		{
			if (e.KeyChar == (char)Keys.Escape)
			{
				this.DialogResult = DialogResult.Cancel;
			}
		}
	}
}