将控件添加到面板中的工作在前几次中起作用，然后逐渐消失

Question

Here's screenshots:

Here's the code I'm using to load the pictureBoxes to the Panel:

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 WebServiceScanner
{
    public partial class MainForm : Form
    {
        int pictureYPosition = 8;
        public MainForm()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            LoadImageFromScanner();
        }

        private void LoadImageFromScanner()
        {
            Image pic = Image.FromFile(@"C:\Users\Public\Pictures\Sample Pictures\Penguins.jpg");
            PictureBox pictureHolder = new PictureBox();
            pictureHolder.Image = pic;
            pictureHolder.SizeMode = PictureBoxSizeMode.StretchImage;
            pictureHolder.Size = new System.Drawing.Size(180, 250);

            pictureHolder.Location = new Point(13, pictureYPosition);
            panel1.Controls.Add(pictureHolder);

            pictureYPosition += 258;

        }      
    }
}

What could be causing the problem? The Panel has Autoscroll set to true, so maybe that's causing the issue?

IMPORTANT EDIT:

The pictures load absolutely FINE, if I don't touch the scrollbar and leave it in it's initial position (topmost). If I scroll down and add pictures it seems it has a different idea of where the point I'm giving it really is.

Any suggestions?

Answer 1

A panel scrolls its content by adjusting the Location property of its child controls when you move the scrollbar. You need to do this yourself when you add a picture. Fix:

pictureHolder.Location = new Point(13, pictureYPosition + panel1.AutoScrollPosition.Y);

Answer 2

Not sure if this will help. Before you add it to panel call panel1.SuppressLayout() then afterwards call panel1.ResumeLayout(true) .

Another option is use a FlowLayoutPanel instead of manually incrementing the distance every time.

Answer 3

The solution that worked for me was to supresslayout and resumelayout, the one of Scott.

To substract the autoscroll Y position, didnt worked at all.