/// <summary> /// Scrolls the viewport one line up or down /// </summary> /// <param name="direction">Direction</param> public void ScrollViewportVerticallyByLine(VSTE.ScrollDirection direction) => ScrollViewportVerticallyByLines(direction, 1);
/// <summary> /// Scrolls the viewport one page up or down /// </summary> /// <param name="direction">Direction</param> /// <returns></returns> public abstract bool ScrollViewportVerticallyByPage(VSTE.ScrollDirection direction);
public override bool ScrollViewportVerticallyByPage(VSTE.ScrollDirection direction)
{
bool hasFullyVisibleLines = hexView.HexViewLines.Any(a => a.VisibilityState == VSTF.VisibilityState.FullyVisible);
if (direction == VSTE.ScrollDirection.Up)
{
var firstVisibleLine = hexView.HexViewLines.FirstVisibleLine;
if (firstVisibleLine.Height > hexView.ViewportHeight)
{
ScrollViewportVerticallyByPixels(hexView.ViewportHeight);
return(hasFullyVisibleLines);
}
double top;
if (firstVisibleLine.VisibilityState == VSTF.VisibilityState.FullyVisible)
{
if (firstVisibleLine.IsFirstDocumentLine())
{
return(hasFullyVisibleLines);
}
top = firstVisibleLine.Top;
}
else
{
top = firstVisibleLine.Bottom; // Top of next line, which is possibly not in HexViewLines so we can't use its Top prop
}
var line = firstVisibleLine;
// Top is only valid if the line is in HexViewLines, so use this variable to track the correct line top value
double lineTop = line.Top;
var prevLine = line;
// Cache this since prevLine could've been disposed when we need to access this property
var prevLineStart = prevLine.BufferStart;
while (lineTop + hexView.ViewportHeight >= top)
{
prevLine = line;
prevLineStart = prevLine.BufferStart;
if (line.IsFirstDocumentLine())
{
break;
}
line = hexView.GetHexViewLineContainingBufferPosition(line.BufferStart - 1);
if (line.VisibilityState == VSTF.VisibilityState.Unattached)
{
// Height is only fully initialized once it's been shown on the screen
// (its LineTransform property is used to calculate Height)
var lineStart = line.BufferStart;
hexView.DisplayHexLineContainingBufferPosition(lineStart, 0, VSTE.ViewRelativePosition.Bottom);
line = hexView.GetHexViewLineContainingBufferPosition(lineStart);
Debug.Assert(line.VisibilityState != VSTF.VisibilityState.Unattached);
}
lineTop -= line.Height;
}
hexView.DisplayHexLineContainingBufferPosition(prevLineStart, 0, VSTE.ViewRelativePosition.Top);
}
else
{
Debug.Assert(direction == VSTE.ScrollDirection.Down);
double pixels = hexView.ViewportHeight;
var lastVisibleLine = hexView.HexViewLines.LastVisibleLine;
if (lastVisibleLine.Height > hexView.ViewportHeight)
{
// This line intentionally left blank
}
else if (lastVisibleLine.VisibilityState == VSTF.VisibilityState.FullyVisible)
{
if (lastVisibleLine.IsLastDocumentLine())
{
hexView.DisplayHexLineContainingBufferPosition(lastVisibleLine.BufferStart, 0, VSTE.ViewRelativePosition.Top);
return(hasFullyVisibleLines);
}
}
else
{
pixels -= hexView.ViewportBottom - lastVisibleLine.Top;
}
ScrollViewportVerticallyByPixels(-pixels);
}
return(hasFullyVisibleLines);
}
/// <summary> /// Scrolls the viewport by lines /// </summary> /// <param name="direction">Direction</param> /// <param name="count">Number of lines to scroll</param> public abstract void ScrollViewportVerticallyByLines(VSTE.ScrollDirection direction, int count);
public override void ScrollViewportVerticallyByLines(VSTE.ScrollDirection direction, int count)
{
if (count < 0)
{
throw new ArgumentOutOfRangeException(nameof(count));
}
if (direction == VSTE.ScrollDirection.Up)
{
double pixels = 0;
var line = hexView.HexViewLines.FirstVisibleLine;
for (int i = 0; i < count; i++)
{
if (i == 0)
{
if (line.VisibilityState == VSTF.VisibilityState.PartiallyVisible)
{
pixels += hexView.ViewportTop - line.Top;
}
if (line.BufferStart > hexView.BufferLines.BufferStart)
{
line = hexView.GetHexViewLineContainingBufferPosition(line.BufferStart - 1);
pixels += line.Height;
}
}
else
{
if (line.VisibilityState == VSTF.VisibilityState.Unattached)
{
// Height is only fully initialized once it's been shown on the screen
// (its LineTransform property is used to calculate Height)
var lineStart = line.BufferStart;
hexView.DisplayHexLineContainingBufferPosition(lineStart, 0, VSTE.ViewRelativePosition.Top);
line = hexView.GetHexViewLineContainingBufferPosition(lineStart);
Debug.Assert(line.VisibilityState != VSTF.VisibilityState.Unattached);
pixels = 0;
}
else
{
pixels += line.Height;
}
}
if (line.BufferStart <= hexView.BufferLines.BufferStart)
{
break;
}
line = hexView.GetHexViewLineContainingBufferPosition(line.BufferStart - 1);
}
if (pixels != 0)
{
ScrollViewportVerticallyByPixels(pixels);
}
}
else
{
Debug.Assert(direction == VSTE.ScrollDirection.Down);
double pixels = 0;
var line = hexView.HexViewLines.FirstVisibleLine;
for (int i = 0; i < count; i++)
{
if (line.IsLastDocumentLine())
{
break;
}
if (i == 0)
{
if (line.VisibilityState == VSTF.VisibilityState.FullyVisible)
{
pixels += line.Height;
}
else
{
pixels += line.Bottom - hexView.ViewportTop;
line = hexView.GetHexViewLineContainingBufferPosition(line.BufferEnd);
pixels += line.Height;
}
}
else
{
if (line.VisibilityState == VSTF.VisibilityState.Unattached)
{
// Height is only fully initialized once it's been shown on the screen
// (its LineTransform property is used to calculate Height)
var lineStart = line.BufferStart;
hexView.DisplayHexLineContainingBufferPosition(lineStart, 0, VSTE.ViewRelativePosition.Top);
line = hexView.GetHexViewLineContainingBufferPosition(lineStart);
Debug.Assert(line.VisibilityState != VSTF.VisibilityState.Unattached);
pixels = 0;
}
else
{
pixels += line.Height;
}
}
if (line.IsLastDocumentLine())
{
break;
}
line = hexView.GetHexViewLineContainingBufferPosition(line.BufferEnd);
}
if (pixels != 0)
{
ScrollViewportVerticallyByPixels(-pixels);
}
}
}
