/// <summary>
/// Determines whether the entry is visible or not.
/// </summary>
/// <param name="renderedEntry">The rendered entry.</param>
/// <param name="view">The view to check for (BrailleIoViewRange).</param>
/// <returns>
/// -1 if not visible; 0 if party visible, and 1 if fully visible.
/// </returns>
public virtual int IsEntryVisible(RenderElement renderedEntry, IViewBoxModel view = null)
{
if (!renderedEntry.IsEmpty())
{
if (view == null)
{
view = _lastView;
}
if (view != null && view.ContentBox.Width * view.ContentBox.Height > 0)
{
int left, top, right, bottom;
left = top = 0;
if (view is IPannable)
{
left = ((IPannable)view).GetXOffset();
top = ((IPannable)view).GetYOffset();
}
right = view.ContentBox.Width + left;
bottom = view.ContentBox.Height + top;
if (renderedEntry.IsInArea(left, left + right, top, top + bottom))
{
if (renderedEntry.IsCompletelyInArea(left, right, top, bottom))
{
return(1);
}
return(0);
}
}
}
return(-1);
}
/// <summary>
/// Makes the entry visible in the given view.
/// If an entry is outside the visible area and the view is <see cref="BrailleIO.Interface.IPannable" />,
/// the offsets are adapted to make the entry visible.
/// </summary>
/// <param name="renderedEntry">The rendered entry.</param>
/// <param name="view">The view.</param>
/// <param name="vertical">if set to <c>true</c> adapt view in vertical direction.</param>
/// <param name="horizontal">if set to <c>true</c> adapt view in horizontal direction.</param>
/// <returns>
/// <c>true</c> if the entry would be visible; otherwise, <c>false</c>.
/// </returns>
/// <remarks>
/// After a returning <c>true</c> you have to force an rerendering.
/// </remarks>
public virtual bool MakeEntryVisible(RenderElement renderedEntry, IViewBoxModel view = null,
bool vertical = true, bool horizontal = false)
{
bool success = false;
if (!renderedEntry.IsEmpty() && (vertical || horizontal))
{
if (view == null)
{
view = _lastView;
}
if (view != null && view.ContentBox.Width * view.ContentBox.Height > 0)
{
int visibility = IsEntryVisible(renderedEntry, view);
if (visibility > 0)
{
return(true);
}
else
{
if (view is IPannable)
{
// entry position
Rectangle bbox = new Rectangle(
renderedEntry.X, renderedEntry.Y,
renderedEntry.Width, renderedEntry.Height);
// visible view port
Rectangle viewPort = new Rectangle(
-((IPannable)view).GetXOffset(),
-((IPannable)view).GetYOffset(),
view.ContentBox.Width,
view.ContentBox.Height);
// check if item is selected --> add one more line for marking
var entry = renderedEntry.GetValue() as DialogEntry;
if (entry != null && entry.Status.HasFlag(DialogEntryStatus.Selected))
{
bbox.Height += 1;
}
// check for scrolling directions
/************** vertical ***********/
if (vertical)
{
if (bbox.Top < viewPort.Top) //entry starts over the view port // move upwards
{
viewPort.Y = bbox.Y;
}
else if (bbox.Bottom > viewPort.Bottom) // entry ends after the view port // move downwards?
{
int newY = viewPort.Top + (bbox.Bottom - viewPort.Bottom);
viewPort.Y = Math.Min(bbox.Top, newY);
}
((IPannable)view).SetYOffset(-viewPort.Y);
success = ((IPannable)view).GetYOffset() == -viewPort.Y;
}
/************ horizontal ***********/
if (horizontal)
{
if (bbox.Left < viewPort.Left) // move right
{
viewPort.X = bbox.X;
}
else if (bbox.Right > viewPort.Right) // move left?
{
int newX = viewPort.Left + (bbox.Right - viewPort.Right);
viewPort.X = Math.Min(bbox.Left, newX);
}
((IPannable)view).SetXOffset(-viewPort.X);
success = true;
}
}
}
}
}
return(success);
}
