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Auto scroll horizontally while adding columns to a ListView

I want to auto scroll the ListView horizontally to the last column every time a ColumnHeader is added.
I need only to scroll to the last Column, not to the item.
listView1.Alignment is set to Left
listView1.View is set to View.Details
I tried this, but it doesn't do anything:
listView1.AutoScrollOffset = new Point(listView1.AutoScrollOffset.X-10, 0);`
This only works if I add only items:
listView1.EnsureVisible(0);
string rowstr = "Test,";
for (var i = 0; i < 10; i++)
{
Debug.WriteLine(i);
ColumnHeader head = new ColumnHeader();
head.Text = i.toString();
listView1.Columns.Add(head);
listView1.Columns[i].Width = 65;
rowstr += "Test"+",";
string[] row = rowstr.Split(",");
var listViewItem = new ListViewItem(row);
listViewItem.Font = new Font("Consolas", 10f);
listView1.Items.Insert(0, listViewItem);
//listView1.EnsureVisible(0);
listView1.AutoScrollOffset = new Point(listView1.AutoScrollOffset.X-10, 0);
}
I didn't try to override WndProc or to call a User32 function, but if this is the only option any help is appreciated.
If it's possibile without PInvoking, that would be better.

To scroll horizontally a ListView, you can send a LVM_SCROLL message to the Control, setting wParam to a value that correspond to position (in pixels) to scroll to.
The position is relative to the current offset.
Set lParam to scroll vertically.
Since you want to scroll to the last Column and the ListView is in Details mode, you can just pass int.MaxValue as the offset: the Win32 Control will do the adjustment (it does it anyway).
[DllImport("user32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
internal static extern int SendMessage(IntPtr hWnd, int uMsg, int wParam, int lParam);
private const int LVM_SCROLL = 0x1014;
SendMessage(listView1.Handle, LVM_SCROLL, int.MaxValue, 0);
EDIT:
Modify your code, adding an interval between the each Column/ListItem insertion, to see it in slow motion. You can use a Button.Click handler.
private async void SomeButton_Click(object sender, EventArgs e)
{
for (int idx = 0; idx < 10; idx++) {
var head = new ColumnHeader() {
Text = idx.ToString(),
Width = 65
};
listView1.Columns.Add(head);
SendMessage(listView1.Handle, LVM_SCROLL, int.MaxValue, 0);
var rowArray = new List<string>(Enumerable.Range(0, idx + 1).Select(n => $"Test{n}"));
var listViewItem = new ListViewItem(rowArray.ToArray());
listView1.Items.Insert(0, listViewItem);
SendMessage(listView1.Handle, LVM_SCROLL, int.MaxValue, 0);
await Task.Delay(500);
}
}
Remove the async stuff to let it go free.
To get the current scroll position, if needed, use GetScrollInfo(). E.g.,
var scrollInfo = new SCROLLINFO(SBInfoMask.SIF_ALL);
bool result = GetScrollInfo(listView1.Handle, SBParam.SB_HORZ, ref scrollInfo);
The nPos member of the SCROLLINFO struct returns the current scroll position. nMax the maximum scroll value. Subtract nPage, corresponding to the Control's ClientSize.Width, to get the maximum possible scroll value.
It should be equal to nPos when the thumb is scrolled to the end.
Win32 declarations:
[DllImport("user32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
private static extern bool GetScrollInfo(IntPtr hwnd, SBParam nBar, [In, Out] ref Point lpsi);
[StructLayout(LayoutKind.Sequential)]
internal struct SCROLLINFO
{
public uint cbSize;
public SBInfoMask fMask;
public int nMin;
public int nMax;
public uint nPage;
public int nPos;
public int nTrackPos;
public SCROLLINFO(SBInfoMask mask)
{
cbSize = (uint)Marshal.SizeOf<SCROLLINFO>();
fMask = mask;
nMin = 0; nMax = 0; nPage = 0; nPos = 0; nTrackPos = 0;
}
}
internal enum SBInfoMask : uint
{
SIF_RANGE = 0x1,
SIF_PAGE = 0x2,
SIF_POS = 0x4,
SIF_DISABLENOSCROLL = 0x8,
SIF_TRACKPOS = 0x10,
SIF_ALL = (SIF_RANGE | SIF_PAGE | SIF_POS | SIF_TRACKPOS),
SIF_POSRANGE = (SIF_RANGE | SIF_POS | SIF_PAGE)
}
public enum SBParam : int
{
SB_HORZ = 0x0,
SB_VERT = 0x1,
SB_CTL = 0x2,
SB_BOTH = 0x3
}

You can create a CustomListView and Re_Define the EnsureVisible method
class DataFlowFilterListView : ListView
{
/// <summary>
/// margin from the selected column to the border of listview.
/// </summary>
const int MARGIN = 20;
/// <summary>
/// native windows message to scroll the listview.
/// </summary>
const Int32 LVM_FIRST = 0x1000;
const Int32 LVM_SCROLL = LVM_FIRST + 20;
[DllImport("user32")]
static extern IntPtr SendMessage(IntPtr Handle, Int32 msg, IntPtr wParam,
IntPtr lParam);
private void ScrollHorizontal(int pixelsToScroll)
{
SendMessage(this.Handle, LVM_SCROLL, (IntPtr)pixelsToScroll,
IntPtr.Zero);
}
/// <summary>
/// Ensure visible of a ListViewItem and SubItem Index.
///
///
/// </summary>
/// <param name="item"></param>
/// <param name="subItemIndex"></param>
public void EnsureVisible(ListViewItem item, int subItemIndex)
{
if (item == null || subItemIndex > item.SubItems.Count - 1)
{
throw new ArgumentException();
}
// scroll to the item row.
item.EnsureVisible();
ScrollToRectangle(item.SubItems[subItemIndex].Bounds.Width);
}
/// <summary>
/// Scrolls the listview.
/// </summary>
/// <param name="bounds"></param>
private void ScrollToRectangle(int width)
{
this.ScrollHorizontal(width);
}
}
Now you can use DataFlowFilterListView instead of ListView.
Execute the following code each time you add a column to the list
listView1.EnsureVisible(listView1.Items[0], 0);

My solution is using user32 function and SendMessage().
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, int wParam, int lParam);
private const int WM_HSCROLL = 0x114; //for horizontal scroll
private const int WPARAM = 7; //to scroll to end
Implementation:
string rowstr = "Code,"
for (var i = 0; i < 10; i++)
{
ColumnHeader head = new ColumnHeader();
head.Text = i.toString();
listView1.Columns.Add(head);
listView1.Columns[i].Width = 65;
rowstr += "Test"+",";
string[] row = rowstr.Split(",");
var listViewItem = new ListViewItem(row);
listViewItem.Font = new Font("Consolas", 10f);
listView1.Items.Insert(0, listViewItem);
SendMessage(listView1.Handle, WM_HSCROLL, WPARAM, 0);
}

How to load lots of icons into ListView quickly from files dragged & dropped?

I would like to load the icons from multiple files dragged onto a listview and some of the information of those files, but the process is going very slow.
In my test, a list of 381 files dragged (some are not exe so those are skipped in my code), takes over 2 minutes to load the icon from the file, and add them to the listview.
Following is condensed version of my code :
public Form1()
{
InitializeComponent();
listView1.DragEnter += ListView1_DragEnter;
listView1.DragDrop += ListView1_DragDrop;
listView1.LargeImageList = new ImageList() { ImageSize = new Size( 64, 64) };
listView1.SmallImageList = new ImageList();
listView1.AllowDrop = true;
}
private void ListView1_DragDrop(object sender, DragEventArgs e)
{
if(e.Data.GetDataPresent(DataFormats.FileDrop))
{
string[] values = (string[])e.Data.GetData(DataFormats.FileDrop);
Convert.IconExtractor i = new Convert.IconExtractor();
foreach (var v in values)
{
var info = new FileInfo(v);
if(info.Extension.ToLower() == ".exe")
{
ListViewItem item = new ListViewItem();
listView1.LargeImageList.Images.Add(i.Extract(info.FullName, Convert.IconSize.Large));
listView1.SmallImageList.Images.Add(i.Extract(info.FullName, Convert.IconSize.Small));
item.Text = Path.GetFileNameWithoutExtension(info.FullName);
item.ImageIndex = listView1.SmallImageList.Images.Count -1;
item.Tag = info.FullName;
listView1.Items.Add(item);
}
}
listView1.Refresh();
}
}
private void ListView1_DragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
{
e.Effect = DragDropEffects.All;
}
}
The method used for extraction is pasted here for convenience :
public enum IconSize
{
Small,
Large
}
public class IconExtractor
{
//----------------------------------------------------------------------------
//
// Description: Extracts the icon associated with any file on your system.
// Author: WidgetMan http://softwidgets.com
//
// Remarks...
//
// Class requires the IconSize enumeration that is implemented in this
// same file. For best results, draw an icon from within a control's Paint
// event via the e.Graphics.DrawIcon method.
//
//----------------------------------------------------------------------------
private const int SHGFI_ICON = 0x100;
private const int SHGFI_SMALLICON = 0x1;
private const int SHGFI_LARGEICON = 0x0;
private struct SHFILEINFO
{
public IntPtr hIcon;
public int iIcon;
public int dwAttributes;
[VBFixedString(260), MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
public string szDisplayName;
[VBFixedString(80), MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
public string szTypeName;
}
[DllImport("shell32", EntryPoint = "SHGetFileInfoA", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int SHGetFileInfo(string pszPath, int dwFileAttributes, ref SHFILEINFO psfi, int ByValcbFileInfo, int uFlags);
public IconExtractor()
{
}
public System.Drawing.Icon Extract(string File, IconSize Size)
{
SHFILEINFO aSHFileInfo = default(SHFILEINFO);
int cbFileInfo = 0;
int uflags = 0;
System.Drawing.Icon Icon = default(System.Drawing.Icon);
switch (Size)
{
case IconSize.Large:
uflags = SHGFI_ICON | SHGFI_LARGEICON;
break;
default:
uflags = SHGFI_ICON | SHGFI_SMALLICON;
break;
}
cbFileInfo = Marshal.SizeOf(aSHFileInfo);
SHGetFileInfo(File, 0, ref aSHFileInfo, cbFileInfo, uflags);
Icon = System.Drawing.Icon.FromHandle(aSHFileInfo.hIcon);
return Icon;
}
public System.Drawing.Icon Extract(string File)
{
return this.Extract(File, IconSize.Small);
}
}
}
What can I do to make this process quick. The concept is to make a quick launcher for multiple applications.
Also of note, while this process is happening, the drag-collection icon is still 'hung' on windows explorer until the drag & drop task has completed fully (looped through all the files).
Here is a rough draft to give a visual of the application:
(yes, i know the icons extracted look like crap as well, but I think that is a separate issue from the slow issue I am having)

My advice is not to load all 381 icons in one step, particularly if the items are not visible. Load them on demand as items are scrolled into view, of if the view is large enough, load them in the background using your threading/task/concurrency technology of choice.
That's what Windows does.
To speed up loading, you may want to use the System Image List which would most likely benefit from caching. Here's some code for getting the large icon. Just change size to be SHGFI_ICON for your use.
public static Icon GetLargeIcon(string FileName, bool jumbo, bool useFileAttributes=false)
{
var shinfo = new SHFILEINFO();
uint flags;
flags = SHGFI_SYSICONINDEX;
if (useFileAttributes)
{
flags |= SHGFI_USEFILEATTRIBUTES;
}
var res = SHGetFileInfo(FileName, FILE_ATTRIBUTE_NORMAL, ref shinfo, (uint) Marshal.SizeOf(shinfo), flags);
if (res == IntPtr.Zero)
{
throw (new FileNotFoundException());
}
var iconIndex = shinfo.iIcon;
// Get the System IImageList object from the Shell:
var iidImageList = new Guid("46EB5926-582E-4017-9FDF-E8998DAA0950");
IImageList iml;
var size = jumbo
? SHIL_JUMBO
: SHIL_EXTRALARGE;
var hres = SHGetImageList(size, iidImageList, out iml);
if (hres != 0)
{
throw (new Exception("Error SHGetImageList"));
}
IntPtr hIcon;
const int ILD_TRANSPARENT = 1;
hres = iml.GetIcon(iconIndex, ILD_TRANSPARENT, out hIcon);
var icon = Icon.FromHandle(hIcon);
icon = icon.Clone() as Icon;
var bm = icon.ToBitmap();
DestroyIcon(hIcon);
return icon;
}

How to set a form to top most

What I am trying to do is just set my from, that has a picture box on it, to be the top most object on my computer and stay that way. I have tried to use f.topmost = true; but if when I click on something my form is no longer top most.
I am running my form from a dll (code of dll is below). I have also tried to add in a on load even to my form, which also did nothing.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace pic
{
public class Class1
{
[DllImport("user32.dll", SetLastError = true)]
private static extern UInt32 GetWindowLong(IntPtr hWnd, int nIndex);
[DllImport("user32.dll")]
static extern int SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
[DllImport("user32.dll")]
static extern bool SetLayeredWindowAttributes(IntPtr hwnd, uint crKey, byte bAlpha, uint dwFlags);
public const int GWL_EXSTYLE = -20;
public const int WS_EX_LAYERED = 0x80000;
public const int WS_EX_TRANSPARENT = 0x20;
public const int LWA_ALPHA = 0x2;
public const int LWA_COLORKEY = 0x1;
Form f = new Form();
public void t(int LocalX, int LocalY, string PicLocal, byte transparency)
{
f.Load += new EventHandler(ProgramViwer_Load);
Bitmap bitmap;
// Form f = new Form();
f.BackColor = Color.White;
f.FormBorderStyle = FormBorderStyle.None;
f.Bounds = Screen.PrimaryScreen.Bounds;
bitmap = new Bitmap(PicLocal);
f.Size = new Size(bitmap.Size.Width, bitmap.Size.Height);
f.StartPosition = FormStartPosition.Manual;
f.SetDesktopLocation(LocalX, LocalY);
Application.EnableVisualStyles();
PictureBox PictureBox1 = new PictureBox();
PictureBox1.Location = new System.Drawing.Point(0, 0);
PictureBox1.Image = bitmap;
PictureBox1.Size = new System.Drawing.Size(bitmap.Size.Width, bitmap.Size.Height);
PictureBox1.SizeMode = PictureBoxSizeMode.AutoSize;
f.Controls.Add(PictureBox1);
f.AllowTransparency = true;
SetWindowLong(f.Handle, GWL_EXSTYLE,
(IntPtr)(GetWindowLong(f.Handle, GWL_EXSTYLE) | WS_EX_LAYERED | WS_EX_TRANSPARENT));
// set transparency to 50% (128)
SetLayeredWindowAttributes(f.Handle, 0, transparency, LWA_ALPHA);
Color BackColor = Color.White;
f.TransparencyKey = BackColor;
f.Opacity = transparency / 255f;
Application.Run(f);
}
private void ProgramViwer_Load(object sender, EventArgs e)
{
f.TopMost = true;
}
}
}

Your problem is that other windows set their 'TopMost' property to true as well. It's not the cleanest solution but it should work.
new Thread(() =>
{
try
{
while (true)
{
this.TopMost = true;
Thread.Sleep(1);
}
}
catch (Exception ex) { }
}).Start();

Hosting WPF UserControl in Win32 application using HwndSource

I need to host my WPF UserControl in other window by Handle.
I've tried to use HwndSource:
var userControl = new MyUserControl();
var parameters = new HwndSourceParameters();
parameters.WindowStyle = 0x10000000 | 0x40000000;
parameters.SetPosition(5, 5);
parameters.SetSize(300, 300);
parameters.ParentWindow = parentWindowHwnd;
var src = new HwndSource(parameters);
src.RootVisual = userControl;
But in this case arrows and tab keys don't work.
If I use ElementHost everything is OK:
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr SetParent(IntPtr hWndChild, IntPtr hWndNewParent);
var userControl = new UserControl1();
var elementHost = new ElementHost();
elementHost.Child = userControl;
elementHost.Left = 5;
elementHost.Top = 5;
elementHost.Width = 300;
elementHost.Height = 300;
SetParent(elementHost.Handle, parentWindowHwnd);
How can I get full functionality using HwndSource?

When you are using HwndSource you must register a handler for the windows messages.
this can done by call:
src.AddHook(this.messageHook);
The hook must check for wm_getdlgcode message.
private IntPtr messageHook(IntPtr hwnd, int msg, IntPtr wparam, IntPtr lparam, ref bool handled)
{
switch (msg)
{
case WmGetDlgCode:
{
handled = true;
return (IntPtr)(DlgcWantChars | DlgcWantTab | DlgcWantArrows | DlgcWantAllKeys);
}
}
return IntPtr.Zero;
}
return via Dlgc_WantChars, Dlgc_WantTab, Dlgc_WantArrows and Dlgc_WantAllKeys what you need.
check this for the message and codes:
http://msdn.microsoft.com/en-us/library/windows/desktop/ms645425(v=vs.85).aspx
private const int WmGetDlgCode = 0x0087;
private const int DlgcWantChars = 0x0080;
private const int DlgcWantTab = 0x0002;
private const int DlgcWantAllKeys = 0x0004;
private const int DlgcWantArrows = 0x0001;

Scrolling Notepad using C# and WIN32

I'm trying to scroll a Notepad window using a C# application. The relevant code block is below, the call to move/size the window works so I know the handle is valid
please can you see what I am missing nothing happens when this is run.
[Flags]
public enum SetWindowPosFlags : uint
{
SWP_ASYNCWINDOWPOS = 0x4000,
SWP_DEFERERASE = 0x2000,
SWP_DRAWFRAME = 0x0020,
SWP_FRAMECHANGED = 0x0020,
SWP_HIDEWINDOW = 0x0080,
SWP_NOACTIVATE = 0x0010,
SWP_NOCOPYBITS = 0x0100,
SWP_NOMOVE = 0x0002,
SWP_NOOWNERZORDER = 0x0200,
SWP_NOREDRAW = 0x0008,
SWP_NOREPOSITION = 0x0200,
SWP_NOSENDCHANGING = 0x0400,
SWP_NOSIZE = 0x0001,
SWP_NOZORDER = 0x0004,
SWP_SHOWWINDOW = 0x0040,
}
private const int WM_SCROLL = 276; // Horizontal scroll
private const int WM_VSCROLL = 277; // Vertical scroll
private const int SB_LINEUP = 0; // Scrolls one line up
private const int SB_LINELEFT = 0;// Scrolls one cell left
private const int SB_LINEDOWN = 1; // Scrolls one line down
private const int SB_LINERIGHT = 1;// Scrolls one cell right
private const int SB_PAGEUP = 2; // Scrolls one page up
private const int SB_PAGELEFT = 2;// Scrolls one page left
private const int SB_PAGEDOWN = 3; // Scrolls one page down
private const int SB_PAGERIGTH = 3; // Scrolls one page right
private const int SB_PAGETOP = 6; // Scrolls to the upper left
private const int SB_LEFT = 6; // Scrolls to the left
private const int SB_PAGEBOTTOM = 7; // Scrolls to the upper right
private const int SB_RIGHT = 7; // Scrolls to the right
private const int SB_ENDSCROLL = 8; // Ends scroll
[DllImport("user32.dll", CharSet = CharSet.Auto)]
private static extern IntPtr SendMessage(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter, int X, int Y, int cx, int cy, SetWindowPosFlags uFlags);
public void scroll()
{
IntPtr handle = IntPtr.Zero;
Process[] processes = Process.GetProcessesByName("Notepad");
foreach (Process p in processes)
{
handle = p.MainWindowHandle;
Console.WriteLine("Got Handle: " + p.MainWindowTitle);
break;
}
//this is to test I have a valid handle
SetWindowPos(handle, new IntPtr(0), 10, 10, 1024, 350, SetWindowPosFlags.SWP_DRAWFRAME);
SendMessage(handle, WM_VSCROLL, (IntPtr)SB_LINEDOWN, IntPtr.Zero);
SendMessage(handle, WM_VSCROLL, (IntPtr)SB_PAGEDOWN, IntPtr.Zero);
}

This fails because you are sending the WM_VSCROLL message to the main window. You need to send the message to Notepad's edit control, which is the window with the scrollbar.
You can enumerate Notepad's child windows using EnumChildWindows. The child with class "Edit" is the one you want.