public static RectangleF GetTextSize(CTFrame frame)
{
var minY = float.MaxValue;
var maxY = float.MinValue;
float width = 0;
var lines = frame.GetLines();
var origins = new CGPoint[lines.Length];
frame.GetLineOrigins(new NSRange(0, 0), origins);
for (var i = 0; i < lines.Length; i++)
{
var line = lines[i];
var lineWidth = (float)line.GetTypographicBounds(out var ascent, out var descent, out var leading);
if (lineWidth > width)
{
width = lineWidth;
}
var origin = origins[i];
minY = (float)Math.Min(minY, origin.Y - ascent);
maxY = (float)Math.Max(maxY, origin.Y + descent);
lines[i].Dispose();
}
return(new RectangleF(0f, minY, width, Math.Max(0, maxY - minY)));
}
// Helper method for drawing the current selection range (as a simple filled rect)
void DrawRangeAsSelection(NSRange selectionRange)
{
// If not in editing mode, we do not draw selection rects
if (!IsEditing)
{
return;
}
// If selection range empty, do not draw
if (selectionRange.Length == 0 || selectionRange.Location == NSRange.NotFound)
{
return;
}
// set the fill color to the selection color
SelectionColor.SetFill();
// Iterate over the lines in our CTFrame, looking for lines that intersect
// with the given selection range, and draw a selection rect for each intersection
var lines = frame.GetLines();
for (int i = 0; i < lines.Length; i++)
{
CTLine line = lines [i];
NSRange lineRange = line.StringRange;
NSRange range = new NSRange(lineRange.Location, lineRange.Length);
NSRange intersection = RangeIntersection(range, selectionRange);
if (intersection.Location != NSRange.NotFound && intersection.Length > 0)
{
// The text range for this line intersects our selection range
nfloat xStart = line.GetOffsetForStringIndex(intersection.Location);
nfloat xEnd = line.GetOffsetForStringIndex(intersection.Location + intersection.Length);
var origin = new CGPoint [lines.Length];
// Get coordinate and bounds information for the intersection text range
frame.GetLineOrigins(new NSRange(i, 0), origin);
nfloat ascent, descent, leading;
line.GetTypographicBounds(out ascent, out descent, out leading);
// Create a rect for the intersection and draw it with selection color
CGRect selectionRect = new CGRect(xStart, origin [0].Y - descent, xEnd - xStart, ascent + descent);
UIGraphics.RectFill(selectionRect);
}
}
}