how to stop flickering C# winforms
I have a program that is essentially like a paint application. However, my program has some flickering issues. I have the following line in my code (which should get rid of flickering - but doesn't):
this.SetStyle(ControlStyles.AllPaintingInWmPaint
| ControlStyles.UserPaint | ControlStyles.DoubleBuffer, true);
my code(minus the super and sub classes for the shapes is as follows:
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;
namespace Paint
{
public partial class Paint : Form
{
private Point startPoint;
private Point endPoint;
private Rectangle rect = new Rectangle();
private Int32 brushThickness = 0;
private Boolean drawSPaint = false;
private List<Shapes> listOfShapes = new List<Shapes>();
private Color currentColor;
private Color currentBoarderColor;
private Boolean IsShapeRectangle = false;
private Boolean IsShapeCircle = false;
private Boolean IsShapeLine = false;
public SPaint()
{
InitializeComponent();
this.SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.DoubleBuffer, true);
currentColor = Color.Red;
currentBoarderColor = Color.DodgerBlue;
IsShapeRectangle = true;
}
private void panelArea_Paint(object sender, PaintEventArgs e)
{
Graphics g = panelArea.CreateGraphics();
if (drawSPaint == true)
{
Pen p = new Pen(Color.Blue);
p.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;
if (IsShapeRectangle == true)
{
g.DrawRectangle(p, rect);
}
else if (IsShapeCircle == true)
{
g.DrawEllipse(p, rect);
}
else if (IsShapeLine == true)
{
g.DrawLine(p, startPoint, endPoint);
}
}
foreach (Shapes shape in listOfShapes)
{
shape.Draw(g);
}
}
private void panelArea_MouseDown(object sender, MouseEventArgs e)
{
startPoint.X = e.X;
startPoint.Y = e.Y;
drawSPaint = true;
}
private void panelArea_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == System.Windows.Forms.MouseButtons.Left)
{
if (e.X > startPoint.X)
{
rect.X = startPoint.X;
rect.Width = e.X - startPoint.X;
}
else
{
rect.X = e.X;
rect.Width = startPoint.X - e.X;
}
if (e.Y > startPoint.Y)
{
rect.Y = startPoint.Y;
rect.Height = e.Y - startPoint.Y;
}
else
{
rect.Y = e.Y;
rect.Height = startPoint.Y - e.Y;
}
panelArea.Invalidate();
}
}
private void panelArea_MouseUp(object sender, MouseEventArgs e)
{
endPoint.X = e.X;
endPoint.Y = e.Y;
drawSPaint = false;
if (rect.Width > 0 && rect.Height > 0)
{
if (IsShapeRectangle == true)
{
listOfShapes.Add(new TheRectangles(rect, currentColor, currentBoarderColor, brushThickness));
}
else if (IsShapeCircle == true)
{
listOfShapes.Add(new TheCircles(rect, currentColor, currentBoarderColor, brushThickness));
}
else if (IsShapeLine == true)
{
listOfShapes.Add(new TheLines(startPoint, endPoint, currentColor, currentBoarderColor, brushThickness));
}
panelArea.Invalidate();
}
}
private void rectangleToolStripMenuItem_Click(object sender, EventArgs e)
{
IsShapeRectangle = true;
IsShapeCircle = false;
IsShapeLine = false;
}
private void ellipseToolStripMenuItem_Click(object sender, EventArgs e)
{
IsShapeRectangle = false;
IsShapeCircle = true;
IsShapeLine = false;
}
private void lineToolStripMenuItem_Click(object sender, EventArgs e)
{
IsShapeCircle = false;
IsShapeRectangle = false;
IsShapeLine = true;
}
private void ThicknessLevel0_Click(object sender, EventArgs e)
{
brushThickness = 0;
}
private void ThicknessLevel2_Click(object sender, EventArgs e)
{
brushThickness = 2;
}
private void ThicknessLevel4_Click(object sender, EventArgs e)
{
brushThickness = 4;
}
private void ThicknessLevel6_Click(object sender, EventArgs e)
{
brushThickness = 6;
}
private void ThicknessLevel8_Click(object sender, EventArgs e)
{
brushThickness = 8;
}
private void ThicknessLevel10_Click(object sender, EventArgs e)
{
brushThickness = 10;
}
private void ThicknessLevel12_Click(object sender, EventArgs e)
{
brushThickness = 12;
}
private void ThicknessLevel14_Click(object sender, EventArgs e)
{
brushThickness = 14;
}
private void FillColour_Click(object sender, EventArgs e)
{
ColorDialog fillColourDialog = new ColorDialog();
fillColourDialog.ShowDialog();
currentColor = fillColourDialog.Color;
panelArea.Invalidate();
}
private void button1_Click(object sender, EventArgs e)
{
ColorDialog fillColourDialog = new ColorDialog();
fillColourDialog.ShowDialog();
currentBoarderColor = fillColourDialog.Color;
panelArea.Invalidate();
}
}
}
How do i stop the flickering?
*UPDATE:*This code actually works great when i'm drawing directly on the form. However, when i try to draw on the panel, flickering becomes an issue
最佳答案