Hello, I posted a similar but less specific question a couple hours ago, but the circumstances have changed. I'm working on a program that transforms graphics, presenting them in a panel in the upper left of the form. It was painting fine earlier, but now isn't and I can't undo, load old version, etc. Previously, the app was unresponsive even to events in the menus, as well as painting. I started a new project and got it up and running, the menus work and I brought over the buttons and stuff. But it still won't paint the axes and gridlines in the panel. I put breakpoints in both the main forms's paint handler and the splitContainer2_Panel1_Paint handler that should be doing the work, but the code here isn't even being executed. I have a timer that's active and invalidating the whole form every 100 ms, so why would the paint event handler not be called? Help?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
namespace TransformerA
{
public partial class Transformer : Form
{
/* Initialize parameters */
private bool drawAxes = true;
private bool drawGrid = true;
private List<ObjectSettings> dispObjects = new List<ObjectSettings>();
/* Initialize form */
public Transformer()
{
InitializeComponent();
}
private void Transformer_Load(object sender, EventArgs e)
{
// Populate available objects listbox
string currentDir = Directory.GetCurrentDirectory();
string[] fileEntries = Directory.GetFiles(currentDir + @"\Objects");
foreach (string s in fileEntries) {
int start = s.LastIndexOf(@"\");
int end = s.LastIndexOf(@".");
availObjectsListBox.Items.Add(s.Substring(start + 1, end - start - 1));
} // end foreach
}
/* Paint graphics */
// Paint main form
private void Transformer_Paint(object sender, PaintEventArgs e)
{
splitContainer2_Panel1_Paint(sender, e);
}
// Paint graphics panel
private void splitContainer2_Panel1_Paint(object sender, PaintEventArgs e)
{
Rectangle r = splitContainer2.Panel1.ClientRectangle;
//Graphics g = splitContainer2.Panel1.CreateGraphics();
Graphics g = e.Graphics;
Pen axisPen = new Pen(Color.Gray, 2.0f);
Pen gridPen = new Pen(Color.Gray, 1.0f);
g.Clear(Color.Blue);
if (drawAxes) {
g.DrawLine(axisPen, r.Left + 0.5f * r.Width, r.Top, r.Left + 0.5f * r.Width, r.Bottom);
g.DrawLine(axisPen, r.Left, r.Top + 0.5f * r.Height, r.Right, r.Top + 0.5f * r.Height);
}
if (drawGrid) {
// Vertical lines
int xVal = 0;
int xCenter = r.Width / 2;
g.DrawLine(gridPen, xCenter, r.Top, xCenter, r.Bottom);
for (int i = 0; i < 10; i++) {
xVal += r.Width / 20;
g.DrawLine(gridPen, xCenter + xVal, r.Top, xCenter + xVal, r.Bottom);
g.DrawLine(gridPen, xCenter - xVal, r.Top, xCenter - xVal, r.Bottom);
}
// Horizontal lines
int yVal = 0;
int yCenter = r.Height / 2;
g.DrawLine(gridPen, r.Left, yCenter, r.Right, yCenter);
for (int i = 0; i < 10; i++) {
yVal += r.Height / 20;
g.DrawLine(gridPen, r.Left, yCenter + yVal, r.Right, yCenter + yVal);
g.DrawLine(gridPen, r.Left, yCenter - yVal, r.Right, yCenter - yVal);
}
}
// foreach object in displayed objects
// keep list of displayed objects and their settings (make struct)
g.Dispose();
axisPen.Dispose();
gridPen.Dispose();
}
/* File menu */
private void saveImageToolStripMenuItem_Click(object sender, EventArgs e)
{
}
private void exitToolStripMenuItem_Click(object sender, EventArgs e)
{
Close();
}
/* Options menu */
private void axesOnoffToolStripMenuItem_Click(object sender, EventArgs e)
{
if (drawAxes == true)
drawAxes = false;
else
drawAxes = true;
}
private void gridOnoffToolStripMenuItem_Click(object sender, EventArgs e)
{
if (drawGrid == true)
drawGrid = false;
else
drawGrid = true;
}
/* Help menu */
private void helpToolStripMenuItem_Click(object sender, EventArgs e)
{
AboutBox dlg = new AboutBox();
dlg.ShowDialog();
}
/* Other */
private void timer1_Tick(object sender, EventArgs e)
{
Invalidate();
}
}
}