private int _browseCallbackHandler(IntPtr hDlg, int msg, IntPtr lParam, IntPtr lpData)
{
switch (msg)
{
case Win32.BFFM_INITIALIZED:
// remove context help button from dialog caption
int lStyle = Win32.GetWindowLong(hDlg, Win32.GWL_STYLE);
lStyle &= ~Win32.DS_CONTEXTHELP;
Win32.SetWindowLong(hDlg, Win32.GWL_STYLE, lStyle);
lStyle = Win32.GetWindowLong(hDlg, Win32.GWL_EXSTYLE);
lStyle &= ~Win32.WS_EX_CONTEXTHELP;
Win32.SetWindowLong(hDlg, Win32.GWL_EXSTYLE, lStyle);
_adjustUi(hDlg, lpData);
break;
case Win32.BFFM_SELCHANGED:
{
bool ok = false;
StringBuilder sb = new StringBuilder(Win32.MAX_PATH);
if (Win32.SHGetPathFromIDList(lParam, sb))
{
ok = true;
string dir = sb.ToString();
IntPtr hEdit = Win32.GetDlgItem(hDlg, CtlIds.PATH_EDIT);
Win32.SetWindowText(hEdit, dir);
#if UsingStatusText
// We're not using status text, but if we were, this is how you'd set it
Win32.SendMessage(hDlg, Win32.BFFM_SETSTATUSTEXTW, 0, dir);
#endif
#if SHBrowseForFolder_lists_links
// This check doesn't seem to be necessary - the SHBrowseForFolder dirtree doesn't seem to list links
Win32.SHFILEINFO sfi = new Win32.SHFILEINFO();
Win32.SHGetFileInfo(lParam, 0, ref sfi, Marshal.SizeOf(sfi), Win32.SHGFI_PIDL | Win32.SHGFI_ATTRIBUTES);
// fail if pidl is a link
if ((sfi.dwAttributes & Win32.SFGAO_LINK) == Win32.SFGAO_LINK)
{
ok = false;
}
#endif
}
// if invalid selection, disable the OK button
if (!ok)
{
Win32.EnableWindow(Win32.GetDlgItem(hDlg, CtlIds.IDOK), false);
}
break;
}
}
return(0);
}
private void _adjustUi(IntPtr hDlg, IntPtr lpData)
{
// Only do the adjustments if InitData was supplied
if (lpData == IntPtr.Zero)
{
return;
}
object obj = Marshal.PtrToStructure(lpData, typeof(InitData));
if (obj is null)
{
return;
}
InitData initdata = (InitData)obj;
// Only do the adjustments if we can find the dirtree control
IntPtr hTree = Win32.GetDlgItem(hDlg, CtlIds.TREEVIEW);
if (hTree == IntPtr.Zero)
{
hTree = Win32.FindWindowEx(IntPtr.Zero, IntPtr.Zero, "SysTreeView32", IntPtr.Zero);
if (hTree == IntPtr.Zero)
{
// This usually means that BIF_NEWDIALOGSTYLE is enabled.
hTree = Win32.FindWindowEx(hDlg, IntPtr.Zero, "SHBrowseForFolder ShellNameSpace Control", IntPtr.Zero);
}
}
if (hTree == IntPtr.Zero)
{
return;
}
// Prep the basic UI
Win32.SendMessage(hDlg, Win32.BFFM_SETSELECTIONW, 1, initdata.InitialPath);
Win32.SetWindowText(hDlg, initdata.Title);
if (initdata.StartPosition == FormStartPosition.CenterParent)
{
_centerTo(hDlg, initdata.hParent);
}
else if (initdata.StartPosition == FormStartPosition.CenterScreen)
{
_centerTo(hDlg, Win32.GetDesktopWindow());
}
// else we do nothing
// Prep the edit box
Win32.RECT rcEdit = new Win32.RECT();
IntPtr hEdit = Win32.GetDlgItem(hDlg, CtlIds.PATH_EDIT);
if (hEdit != IntPtr.Zero)
{
if (initdata.ShowEditbox)
{
Win32.GetWindowRect(hEdit, out rcEdit);
Win32.ScreenToClient(hEdit, ref rcEdit);
}
else
{
Win32.ShowWindow(hEdit, Win32.SW_HIDE);
}
}
// make the dialog larger
Win32.RECT rcDlg;
Win32.GetWindowRect(hDlg, out rcDlg);
rcDlg.Right += 40;
rcDlg.Bottom += 30;
if (hEdit != IntPtr.Zero)
{
rcDlg.Bottom += (rcEdit.Height + 5);
}
Win32.MoveWindow(hDlg, rcDlg, true);
Win32.GetClientRect(hDlg, out rcDlg);
int vMargin = 10;
// Accomodate the resizing handle's width
int hMargin = 10; // SystemInformation.VerticalScrollBarWidth;
// Move the Cancel button
Win32.RECT rcCancel = new Win32.RECT();
IntPtr hCancel = Win32.GetDlgItem(hDlg, CtlIds.IDCANCEL);
if (hCancel != IntPtr.Zero)
{
Win32.GetWindowRect(hCancel, out rcCancel);
Win32.ScreenToClient(hDlg, ref rcCancel);
rcCancel = new Win32.RECT(rcDlg.Right - (rcCancel.Width + hMargin),
rcDlg.Bottom - (rcCancel.Height + vMargin),
rcCancel.Width,
rcCancel.Height);
Win32.MoveWindow(hCancel, rcCancel, false);
}
// Move the OK button
Win32.RECT rcOK = new Win32.RECT();
IntPtr hOK = Win32.GetDlgItem(hDlg, CtlIds.IDOK);
if (hOK != IntPtr.Zero)
{
Win32.GetWindowRect(hOK, out rcOK);
Win32.ScreenToClient(hDlg, ref rcOK);
rcOK = new Win32.RECT(rcCancel.Left - (rcCancel.Width + hMargin),
rcCancel.Top,
rcOK.Width,
rcOK.Height);
Win32.MoveWindow(hOK, rcOK, false);
}
// Manage the "Make New Folder" button
IntPtr hBtn = Win32.GetDlgItem(hDlg, CtlIds.NEW_FOLDER_BUTTON);
if (!initdata.ShowNewFolderButton)
{
// Make sure this button is not visible
Win32.ShowWindow(hBtn, Win32.SW_HIDE);
}
else if (hBtn == IntPtr.Zero)
{
// Create a button - button is only auto-created under BIF_NEWDIALOGSTYLE
// This is failing, and I don't know why!
Win32.CreateWindowEx(0x50010000,
"button",
"&Make New Folder",
0x00000004,
hMargin,
rcOK.Top,
105,
rcOK.Height,
hDlg,
new IntPtr(CtlIds.NEW_FOLDER_BUTTON),
Process.GetCurrentProcess().Handle,
IntPtr.Zero);
}
// Position the path editbox and it's label
// We'll repurpose the Title (static) control as the editbox label
int treeTop = vMargin;
if (hEdit != IntPtr.Zero)
{
int xEdit = hMargin;
int cxEdit = rcDlg.Width - (2 * hMargin);
IntPtr hLabel = Win32.GetDlgItem(hDlg, CtlIds.TITLE);
if (hLabel != IntPtr.Zero)
{
string labelText = "Folder: ";
Win32.SetWindowText(hLabel, labelText);
// This code obtains the required size of the static control that serves as the label for the editbox.
// All this GDI code is a bit excessive, but I figured "what the hell".
IntPtr hdc = Win32.GetDC(hLabel);
IntPtr hFont = Win32.SendMessage(hLabel, Win32.WM_GETFONT, IntPtr.Zero, IntPtr.Zero);
IntPtr oldfnt = Win32.SelectObject(hdc, hFont);
Size szLabel;
Win32.GetTextExtentPoint32(hdc, labelText, labelText.Length, out szLabel);
Win32.SelectObject(hdc, oldfnt);
Win32.ReleaseDC(hLabel, hdc);
Win32.RECT rcLabel = new Win32.RECT(hMargin,
vMargin + ((rcEdit.Height - szLabel.Height) / 2),
szLabel.Width,
szLabel.Height);
Win32.MoveWindow(hLabel, rcLabel, false);
xEdit += rcLabel.Width;
cxEdit -= rcLabel.Width;
}
// Expand the folder tree to fill the dialog
rcEdit = new Win32.RECT(xEdit,
vMargin,
cxEdit,
rcEdit.Height);
Win32.MoveWindow(hEdit, rcEdit, false);
treeTop = rcEdit.Bottom + 5;
}
Win32.RECT rcTree = new Win32.RECT(hMargin,
treeTop,
rcDlg.Width - (2 * hMargin),
rcDlg.Bottom - (treeTop + (2 * vMargin) + rcOK.Height));
Win32.MoveWindow(hTree, rcTree, false);
}