public static void HighlightText(this UILabel textView, string searchText, UIColor foregroundColor, UIColor backgroundColor = null)
{
var highlightMarker = new HighlightMarker(textView.Text, searchText);
var textAttributed = new NSMutableAttributedString(textView.Text);
foreach (var segment in highlightMarker)
{
int fromIndex = segment.FromIndex;
int length = segment.Length;
bool isHighlighted = segment.IsHighlighted;
if (isHighlighted)
{
var colourAttribute = new UIStringAttributes
{
ForegroundColor = foregroundColor,
BackgroundColor = backgroundColor
};
textAttributed.SetAttributes(colourAttribute, new NSRange(fromIndex, length));
}
}
textView.AttributedText = textAttributed;
}
private static void OnTextChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var textBlock = d as TextBlock;
if (textBlock == null)
{
return;
}
string fulltext = GetFullText(textBlock) ?? string.Empty;
string highlightedText = GetHighlightedText(textBlock) ?? string.Empty;
textBlock.Inlines.Clear();
if (string.IsNullOrEmpty(fulltext) || string.IsNullOrEmpty(highlightedText))
{
textBlock.Inlines.Add(new Run {
Text = fulltext
});
return;
}
var foregroundBrush = GetForeground(textBlock) ?? ColorHelper.GetDefaultForegroundBrush();
#if !(WINDOWS_APP || WINDOWS_PHONE || WINDOWS_PHONE_APP || WINDOWS_UWP)
var backgroundBrush = GetBackground(textBlock) ?? ColorHelper.GetDefaultBackgroundBrush();
#endif
var highlightProcessor = GetHighlightProcessor(textBlock);
var highlightMarker = new HighlightMarker(fulltext, highlightedText, highlightProcessor);
foreach (var current in highlightMarker)
{
int fromIndex = current.FromIndex;
int length = current.Length;
bool isHighlighted = current.IsHighlighted;
var inlineRun = new Run {
Text = fulltext.Substring(fromIndex, length)
};
if (isHighlighted)
{
inlineRun.Foreground = foregroundBrush;
#if !(WINDOWS_APP || WINDOWS_PHONE || WINDOWS_PHONE_APP || WINDOWS_UWP)
inlineRun.Background = backgroundBrush;
#endif
}
textBlock.Inlines.Add(inlineRun);
}
}
public static void HighlightText(this TextView textView, string searchText, Color foregroundColor, Color?backgroundColor = null)
{
var highlightMarker = new HighlightMarker(textView.Text, searchText);
var spannableStringBuilder = new SpannableStringBuilder(textView.Text);
foreach (var current in highlightMarker)
{
int fromIndex = current.FromIndex;
int endIndex = fromIndex + current.Length;
bool isHighlighted = current.IsHighlighted;
if (isHighlighted)
{
spannableStringBuilder.SetSpan(new ForegroundColorSpan(foregroundColor), fromIndex, endIndex, SpanTypes.ExclusiveExclusive);
if (backgroundColor.HasValue)
{
spannableStringBuilder.SetSpan(new BackgroundColorSpan(backgroundColor.Value), fromIndex, endIndex, SpanTypes.ExclusiveExclusive);
}
}
}
textView.TextFormatted = spannableStringBuilder;
}
