/// <summary>
/// Method to set the ScrollbarInfo, if we can get it
/// </summary>
/// <param name="forceUpdate">set to true to force an update, default is false</param>
/// <returns>ScrollBarInfo?</returns>
public ScrollBarInfo?GetScrollbarInfo(bool forceUpdate = false)
{
// Prevent updates, if there is already a value
if (ScrollBar.HasValue && !forceUpdate)
{
return(ScrollBar);
}
var objectId = ObjectIdentifiers.Client;
switch (ScrollBarType)
{
case ScrollBarTypes.Control:
objectId = ObjectIdentifiers.Client;
break;
case ScrollBarTypes.Vertical:
objectId = ObjectIdentifiers.VerticalScrollbar;
break;
case ScrollBarTypes.Horizontal:
objectId = ObjectIdentifiers.HorizontalScrollbar;
break;
}
var scrollbarInfo = ScrollBarInfo.Create();
var hasScrollbarInfo = User32Api.GetScrollBarInfo(ScrollBarWindow.Handle, objectId, ref scrollbarInfo);
if (!hasScrollbarInfo)
{
var error = Win32.GetLastErrorCode();
Log.Verbose().WriteLine("Error retrieving Scrollbar info : {0}", Win32.GetMessage(error));
return(null);
}
ScrollBar = scrollbarInfo;
return(scrollbarInfo);
}
/// <summary>
/// Initialises a new instance of ComboTreeDropDown and associates it with its parent ComboTreeBox.
/// </summary>
/// <param name="sourceControl"></param>
public ComboTreeDropDown(ComboTreeBox sourceControl)
{
_visibleItems = new List <NodeInfo>();
_bitmaps = new Dictionary <BitmapInfo, Image>();
_scrollBar = new ScrollBarInfo();
AutoSize = false;
this._sourceControl = sourceControl;
RenderMode = ToolStripRenderMode.System;
BackColor = Color.White;
_dropDownHeight = 150;
_itemHeight = MIN_ITEM_HEIGHT;
Items.Add("");
_scrollRepeater = new Timer();
_scrollRepeater.Tick += new EventHandler(scrollRepeater_Tick);
}
public bool LastLinesVisible()
{
var scrollBarInfo = new ScrollBarInfo();
scrollBarInfo.cbSize = Marshal.SizeOf(scrollBarInfo);
scrollBarInfo.fMask = 0x10 | 0x1 | 0x2;
try
{
GetScrollInfo(this.Handle, 1, ref scrollBarInfo);
}
catch
{
return(true);
}
//if (_ScrollBarInfo.max == 0) return false;
return((scrollBarInfo.max - (scrollBarInfo.nTrackPos + scrollBarInfo.nPage)) < (this.Font.Height * AppendLineAmountOfLastVisibleLinesToAutoScroll_));
}
private int GetScrollValue(ScrollBarInfo info)
{
NativeMethods.ScrollInfo si = new NativeMethods.ScrollInfo();
si.fMask = NativeMethods.SIF_ALL;
si.cbSize = Marshal.SizeOf(si.GetType());
if (!Misc.GetScrollInfo(_hwnd, _sbFlag, ref si))
{
return(0);
}
switch (info)
{
case ScrollBarInfo.CurrentPosition:
//
// Builds prior to Vista 5359 failed to correctly account for RTL scrollbar layouts.
//
if ((Environment.OSVersion.Version.Major < 6) && (_sbFlag == NativeMethods.SB_HORZ) && (Misc.IsControlRTL(_parent._hwnd)))
{
return(GetScrollMaxValue(si) - si.nPos);
}
return(si.nPos);
case ScrollBarInfo.MaximumPosition:
return(GetScrollMaxValue(si));
case ScrollBarInfo.MinimumPosition:
return(si.nMin);
case ScrollBarInfo.PageSize:
return(si.nPage);
case ScrollBarInfo.TrackPosition:
return(si.nTrackPos);
case ScrollBarInfo.LargeChange:
return(si.nPage);
case ScrollBarInfo.SmallChange:
return(1);
}
return(0);
}
private int GetScrollValue (ScrollBarInfo info)
{
NativeMethods.ScrollInfo si = new NativeMethods.ScrollInfo ();
si.fMask = NativeMethods.SIF_ALL;
si.cbSize = Marshal.SizeOf (si.GetType ());
if (!Misc.GetScrollInfo(_hwnd, _sbFlag, ref si))
{
return 0;
}
switch (info)
{
case ScrollBarInfo.CurrentPosition:
//
// Builds prior to Vista 5359 failed to correctly account for RTL scrollbar layouts.
//
if ((Environment.OSVersion.Version.Major < 6) && (_sbFlag == NativeMethods.SB_HORZ) && (Misc.IsControlRTL(_parent._hwnd)))
{
return GetScrollMaxValue(si) - si.nPos;
}
return si.nPos;
case ScrollBarInfo.MaximumPosition:
return GetScrollMaxValue(si);
case ScrollBarInfo.MinimumPosition:
return si.nMin;
case ScrollBarInfo.PageSize:
return si.nPage;
case ScrollBarInfo.TrackPosition:
return si.nTrackPos;
case ScrollBarInfo.LargeChange:
return si.nPage;
case ScrollBarInfo.SmallChange:
return 1;
}
return 0;
}
public static extern bool GetScrollBarInfo(IntPtr hwnd, ObjectIdentifiers idObject, ref ScrollBarInfo scrollBarInfo);
private static extern int GetScrollInfo(IntPtr hwnd, int nBar, ref ScrollBarInfo scrollInfo);
