/// <summary>
/// Initializes a new instance of the BallonToolTip class.
/// </summary>
public BallonToolTip()
{
m_window = new NativeToolTipWindow(this);
m_controls = new Hashtable();
m_addedList = new ArrayList();
m_style = ToolTipStyle.Balloon;
}
/// <summary>
/// Initializes a new instance of the BallonToolTip class.
/// </summary>
public BallonToolTip()
{
m_window = new NativeToolTipWindow(this);
m_controls = new Hashtable();
m_addedList = new ArrayList();
m_style = ToolTipStyle.Balloon;
}
/// <summary>
/// Handle vertical scroll to make it smoother
/// </summary>
/// <remarks>The default scrolling increments are quite small and the frequent redraws cause a messy
/// display when the thumb is dragged. By handling it ourselves, we can initialize and bind the rows
/// before they are displayed and can also control the increments to provide a smoother scroll with a
/// cleaner visual appearance.</remarks>
/// <param name="m">The vertical scroll message parameters</param>
private void HandleVerticalScroll(ref Message m)
{
TemplateControl tc;
DataList owner = (DataList)this.Parent;
Rectangle clientRect = base.ClientRectangle, displayRect = base.DisplayRectangle;
int row, fillRange, maxRows, multiplier, rowHeight = owner.RowHeight, curPos = -displayRect.Y;
int maxPos = -(clientRect.Height - displayRect.Height - rowHeight), scrollEvent = (int)m.WParam & 0xFFFF;
switch (scrollEvent)
{
case 0: // Line up
if (curPos <= 0)
{
curPos = 0;
}
else
{
curPos -= rowHeight;
}
break;
case 1: // Line down
if (curPos >= maxPos - rowHeight)
{
curPos = maxPos;
}
else
{
curPos += rowHeight;
}
break;
case 2: // Page up
if (curPos <= clientRect.Height)
{
curPos = 0;
}
else
{
curPos -= clientRect.Height;
}
break;
case 3: // Page down
if (curPos >= maxPos - clientRect.Height)
{
curPos = maxPos;
}
else
{
curPos += clientRect.Height;
}
break;
case 4: // Thumb position (end tracking)
case 5: // Thumb track (drag)
if (scrollTip == null)
{
scrollTip = new NativeToolTipWindow(this);
}
// Round it to the nearest row start and show the position in a tool tip
curPos = UnsafeNativeMethods.ScrollThumbPosition(base.Handle, 1) / rowHeight * rowHeight;
scrollTip.ShowTooltip(String.Format(CultureInfo.InvariantCulture, LR.GetString("DLScrollPos"),
(curPos / rowHeight) + 1, owner.RowCount));
break;
case 6: // Top
curPos = 0;
break;
case 7: // Bottom
curPos = maxPos;
break;
case 8: // End scroll
if (scrollTip != null && scrollTip.IsVisible)
{
scrollTip.HideTooltip();
}
break;
case 32767: // Custom call to scroll row into view
curPos = m.LParam.ToInt32();
if (curPos < 0)
{
curPos = 0;
}
else
if (curPos >= maxPos)
{
curPos = maxPos;
}
break;
}
// Ignore if not displaying content while scrolling and it was a thumb tracking event
if (this.GetScrollState(0x10) || scrollEvent != 5)
{
// Initialize and bind the rows before they are displayed to smooth out the scrolling
multiplier = (owner.SeparatorsVisible) ? 2 : 1;
if (owner.ListManager != null && this.Controls.Count != 0)
{
maxRows = owner.ListManager.Count;
// Get the range of visible rows
row = curPos / rowHeight;
fillRange = ((curPos + rowHeight + this.Height) / rowHeight) + 1;
if (fillRange < maxRows)
{
maxRows = fillRange;
}
}
else
{
row = maxRows = 0;
}
while (row < maxRows)
{
if (row * multiplier < this.Controls.Count)
{
tc = (TemplateControl)this.Controls[row * multiplier];
}
else
{
tc = null;
}
// By waiting until the templates scroll into view, it saves some time and resources during
// the initial load and only binds what is actually shown.
if (tc != null && !tc.IsNewRowInternal && !tc.HasBeenBound)
{
if (!tc.HasBeenInitialized)
{
tc.InitializeTemplate();
tc.HasBeenInitialized = true;
}
tc.Bind();
tc.HasBeenBound = true;
owner.OnItemDataBound(new DataListEventArgs(row, tc));
}
row++;
}
// Set "user scrolled" flag and update the display rectangle
this.SetScrollState(8, true);
this.SetDisplayRectLocation(displayRect.X, -curPos);
if (syncScrollbars != null)
{
syncScrollbars.Invoke(this, new object[] { this.AutoScroll });
}
// Refresh the row headers if they are visible
if (owner.RowHeadersVisible)
{
owner.Invalidate(new Rectangle(0, 0, owner.RowHeaderWidth, owner.Height), false);
}
}
if (scrollEvent != 8)
{
ScrollEventArgs se = new ScrollEventArgs((ScrollEventType)scrollEvent, -displayRect.Y, curPos,
ScrollOrientation.VerticalScroll);
base.OnScroll(se);
}
}
