我创建了一个用户控件,将屏幕分成矩形,但我的控件正在执行OnPaintBackground
很多次,而它应该只执行一次,请帮助我,因为只执行一次非常重要,因为屏幕开始闪烁很多。
public partial class Schedual : UserControl
{
int days;
public int Days
{
get { return days; }
set
{
days = value;
change = true;
Invalidate(true);
}
}
int periods;
public int Periods
{
get { return periods; }
set
{
periods = value;
change = true;
Invalidate(true);
}
}
Brush brush;
bool change = false;
List<Panel> panels;
public Schedual()
{
InitializeComponent();
this.ResumeLayout(true);
this.days = 1;
this.periods = 1;
brush = Brushes.White;
change = false;
}
protected override void OnPaint(PaintEventArgs e)
{
//stuff ....... or base.OnPaint(e);
}
protected override void OnPaintBackground(PaintEventArgs e)
{
Graphics g = e.Graphics;
var h = this.Height / days;
var w = this.Width / periods;
for (int i = 0; i < days; i++)
{
for (int j = 0; j <= periods; j++)
{
g.FillRectangle(brush, j * w, i * h, w, h);
if (change)
{
AddPanel(j * w, i * h, w, h);
}
g.DrawLine(Pens.Black, 0, i * h, this.Right, i * h); //draw the horizantle lines
g.DrawLine(Pens.Black, j * w, 0, this.Bottom, j * w); //draw the verical lines
}
}
change = false;
}
}
输出是一遍又一遍地绘制背景时屏幕闪烁很多......