IndexedPosition GetPosition(UITextRange range, UITextLayoutDirection direction)
{
// Note that this sample assumes LTR text direction
IndexedRange r = (IndexedRange)range;
int pos = r.Range.Location;
// For this sample, we just return the extent of the given range if the
// given direction is "forward" in a LTR context (UITextLayoutDirectionRight
// or UITextLayoutDirectionDown), otherwise we return just the range position
switch (direction)
{
case UITextLayoutDirection.Up:
case UITextLayoutDirection.Left:
pos = r.Range.Location;
break;
case UITextLayoutDirection.Right:
case UITextLayoutDirection.Down:
pos = r.Range.Location + r.Range.Length;
break;
}
// Return text position using our UITextPosition implementation.
// Note that position is not currently checked against document range.
return(IndexedPosition.GetPosition(pos));
}
void ReplaceRange(UITextRange range, string text)
{
IndexedRange r = (IndexedRange)range;
NSRange selectedNSRange = textView.SelectedTextRange;
// Determine if replaced range intersects current selection range
// and update selection range if so.
if (r.Range.Location + r.Range.Length <= selectedNSRange.Location)
{
// This is the easy case.
selectedNSRange.Location -= (r.Range.Length - text.Length);
}
else
{
// Need to also deal with overlapping ranges. Not addressed
// in this simplified sample.
}
// Now replace characters in text storage
this.text.Remove(r.Range.Location, r.Range.Length);
this.text.Insert(r.Range.Location, text);
// Update underlying SimpleCoreTextView
textView.Text = this.text.ToString();
textView.SelectedTextRange = selectedNSRange;
}
IndexedRange GetTextRange(UITextPosition fromPosition, UITextPosition toPosition)
{
// Generate IndexedPosition instances that wrap the to and from ranges
IndexedPosition @from = (IndexedPosition)fromPosition;
IndexedPosition @to = (IndexedPosition)toPosition;
NSRange range = new NSRange(Math.Min(@from.Index, @to.Index), Math.Abs(to.Index - @from.Index));
return(IndexedRange.GetRange(range));
}
RectangleF FirstRect(UITextRange range)
{
// FIXME: the Objective-C code doesn't get a null range
// This is the reason why we don't get the autocorrection suggestions
// (it'll just autocorrect without showing any suggestions).
// Possibly due to http://bugzilla.xamarin.com/show_bug.cgi?id=265
IndexedRange r = (IndexedRange)(range ?? IndexedRange.GetRange(new NSRange(0, 1)));
// Use underlying SimpleCoreTextView to get rect for range
RectangleF rect = textView.FirstRect(r.Range);
// Convert rect to our view coordinates
return(ConvertRectFromView(rect, textView));
}
public static IndexedRange GetRange(NSRange theRange)
{
IndexedRange result;
if (theRange.Location == NSRange.NotFound)
{
return(null);
}
if (!ranges.TryGetValue(theRange, out result))
{
result = new IndexedRange();
result.Range = new NSRange(theRange.Location, theRange.Length);
}
return(result);
}
IndexedRange GetCharacterRange(UITextPosition position, UITextLayoutDirection direction)
{
// Note that this sample assumes LTR text direction
IndexedPosition pos = (IndexedPosition)position;
NSRange result = new NSRange(pos.Index, 1);
switch (direction)
{
case UITextLayoutDirection.Up:
case UITextLayoutDirection.Left:
result = new NSRange(pos.Index - 1, 1);
break;
case UITextLayoutDirection.Right:
case UITextLayoutDirection.Down:
result = new NSRange(pos.Index, 1);
break;
}
// Return range using our UITextRange implementation
// Note that range is not currently checked against document range.
return(IndexedRange.GetRange(result));
}
string TextInRange(UITextRange range)
{
IndexedRange r = (IndexedRange)range;
return(text.ToString().Substring(r.Range.Location, r.Range.Length));
}