FileDocCategorySizeDatePackage
Linkify.javaAPI DocAndroid 1.5 API18432Wed May 06 22:41:56 BST 2009android.text.util

Linkify

public class Linkify extends Object
Linkify take a piece of text and a regular expression and turns all of the regex matches in the text into clickable links. This is particularly useful for matching things like email addresses, web urls, etc. and making them actionable. Alone with the pattern that is to be matched, a url scheme prefix is also required. Any pattern match that does not begin with the supplied scheme will have the scheme prepended to the matched text when the clickable url is created. For instance, if you are matching web urls you would supply the scheme http://. If the pattern matches example.com, which does not have a url scheme prefix, the supplied scheme will be prepended to create http://example.com when the clickable url link is created.

Fields Summary
public static final int
WEB_URLS
Bit field indicating that web URLs should be matched in methods that take an options mask
public static final int
EMAIL_ADDRESSES
Bit field indicating that email addresses should be matched in methods that take an options mask
public static final int
PHONE_NUMBERS
Bit field indicating that phone numbers should be matched in methods that take an options mask
public static final int
MAP_ADDRESSES
Bit field indicating that street addresses should be matched in methods that take an options mask
public static final int
ALL
Bit mask indicating that all available patterns should be matched in methods that take an options mask
private static final int
PHONE_NUMBER_MINIMUM_DIGITS
Don't treat anything with fewer than this many digits as a phone number.
public static final MatchFilter
sUrlMatchFilter
Filters out web URL matches that occur after an at-sign (@). This is to prevent turning the domain name in an email address into a web link.
public static final MatchFilter
sPhoneNumberMatchFilter
Filters out URL matches that don't have enough digits to be a phone number.
public static final TransformFilter
sPhoneNumberTransformFilter
Transforms matched phone number text into something suitable to be used in a tel: URL. It does this by removing everything but the digits and plus signs. For instance: '+1 (919) 555-1212' becomes '+19195551212'
Constructors Summary
Methods Summary
private static final voidaddLinkMovementMethod(android.widget.TextView t)

        MovementMethod m = t.getMovementMethod();

        if ((m == null) || !(m instanceof LinkMovementMethod)) {
            if (t.getLinksClickable()) {
                t.setMovementMethod(LinkMovementMethod.getInstance());
            }
        }
public static final booleanaddLinks(android.text.Spannable text, int mask)
Scans the text of the provided Spannable and turns all occurrences of the link types indicated in the mask into clickable links. If the mask is nonzero, it also removes any existing URLSpans attached to the Spannable, to avoid problems if you call it repeatedly on the same text.


                                                                                                    
       
                                                                                                                                                                            
              
    

                                                            
       
                                                                                    
             
    

                                                               
            
        if (mask == 0) {
            return false;
        }

        URLSpan[] old = text.getSpans(0, text.length(), URLSpan.class);

        for (int i = old.length - 1; i >= 0; i--) {
            text.removeSpan(old[i]);
        }

        ArrayList<LinkSpec> links = new ArrayList<LinkSpec>();

        if ((mask & WEB_URLS) != 0) {
            gatherLinks(links, text, Regex.WEB_URL_PATTERN,
                new String[] { "http://", "https://" },
                sUrlMatchFilter, null);
        }

        if ((mask & EMAIL_ADDRESSES) != 0) {
            gatherLinks(links, text, Regex.EMAIL_ADDRESS_PATTERN,
                new String[] { "mailto:" },
                null, null);
        }

        if ((mask & PHONE_NUMBERS) != 0) {
            gatherLinks(links, text, Regex.PHONE_PATTERN,
                new String[] { "tel:" },
                sPhoneNumberMatchFilter, sPhoneNumberTransformFilter);
        }

        if ((mask & MAP_ADDRESSES) != 0) {
            gatherMapLinks(links, text);
        }

        pruneOverlaps(links);

        if (links.size() == 0) {
            return false;
        }

        for (LinkSpec link: links) {
            applyLink(link.url, link.start, link.end, text);
        }

        return true;
public static final booleanaddLinks(android.widget.TextView text, int mask)
Scans the text of the provided TextView and turns all occurrences of the link types indicated in the mask into clickable links. If matches are found the movement method for the TextView is set to LinkMovementMethod.

        if (mask == 0) {
            return false;
        }

        CharSequence t = text.getText();

        if (t instanceof Spannable) {
            if (addLinks((Spannable) t, mask)) {
                addLinkMovementMethod(text);
                return true;
            }

            return false;
        } else {
            SpannableString s = SpannableString.valueOf(t);

            if (addLinks(s, mask)) {
                addLinkMovementMethod(text);
                text.setText(s);

                return true;
            }

            return false;
        }
public static final voidaddLinks(android.widget.TextView text, java.util.regex.Pattern pattern, java.lang.String scheme)
Applies a regex to the text of a TextView turning the matches into links. If links are found then UrlSpans are applied to the link text match areas, and the movement method for the text is changed to LinkMovementMethod.

param
text TextView whose text is to be marked-up with links
param
pattern Regex pattern to be used for finding links
param
scheme Url scheme string (eg http:// to be prepended to the url of links that do not have a scheme specified in the link text

        addLinks(text, pattern, scheme, null, null);
public static final voidaddLinks(android.widget.TextView text, java.util.regex.Pattern p, java.lang.String scheme, android.text.util.Linkify$MatchFilter matchFilter, android.text.util.Linkify$TransformFilter transformFilter)
Applies a regex to the text of a TextView turning the matches into links. If links are found then UrlSpans are applied to the link text match areas, and the movement method for the text is changed to LinkMovementMethod.

param
text TextView whose text is to be marked-up with links
param
p Regex pattern to be used for finding links
param
scheme Url scheme string (eg http:// to be prepended to the url of links that do not have a scheme specified in the link text
param
matchFilter The filter that is used to allow the client code additional control over which pattern matches are to be converted into links.

        SpannableString s = SpannableString.valueOf(text.getText());

        if (addLinks(s, p, scheme, matchFilter, transformFilter)) {
            text.setText(s);
            addLinkMovementMethod(text);
        }
public static final booleanaddLinks(android.text.Spannable text, java.util.regex.Pattern pattern, java.lang.String scheme)
Applies a regex to a Spannable turning the matches into links.

param
text Spannable whose text is to be marked-up with links
param
pattern Regex pattern to be used for finding links
param
scheme Url scheme string (eg http:// to be prepended to the url of links that do not have a scheme specified in the link text

        return addLinks(text, pattern, scheme, null, null);
public static final booleanaddLinks(android.text.Spannable s, java.util.regex.Pattern p, java.lang.String scheme, android.text.util.Linkify$MatchFilter matchFilter, android.text.util.Linkify$TransformFilter transformFilter)
Applies a regex to a Spannable turning the matches into links.

param
s Spannable whose text is to be marked-up with links
param
p Regex pattern to be used for finding links
param
scheme Url scheme string (eg http:// to be prepended to the url of links that do not have a scheme specified in the link text
param
matchFilter The filter that is used to allow the client code additional control over which pattern matches are to be converted into links.

        boolean hasMatches = false;
        String prefix = (scheme == null) ? "" : scheme.toLowerCase();
        Matcher m = p.matcher(s);

        while (m.find()) {
            int start = m.start();
            int end = m.end();
            boolean allowed = true;

            if (matchFilter != null) {
                allowed = matchFilter.acceptMatch(s, start, end);
            }

            if (allowed) {
                String url = makeUrl(m.group(0), new String[] { prefix },
                                     m, transformFilter);

                applyLink(url, start, end, s);
                hasMatches = true;
            }
        }

        return hasMatches;
private static final voidapplyLink(java.lang.String url, int start, int end, android.text.Spannable text)

        URLSpan span = new URLSpan(url);

        text.setSpan(span, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
private static final voidgatherLinks(java.util.ArrayList links, android.text.Spannable s, java.util.regex.Pattern pattern, java.lang.String[] schemes, android.text.util.Linkify$MatchFilter matchFilter, android.text.util.Linkify$TransformFilter transformFilter)

        Matcher m = pattern.matcher(s);

        while (m.find()) {
            int start = m.start();
            int end = m.end();

            if (matchFilter == null || matchFilter.acceptMatch(s, start, end)) {
                LinkSpec spec = new LinkSpec();
                String url = makeUrl(m.group(0), schemes, m, transformFilter);

                spec.url = url;
                spec.start = start;
                spec.end = end;

                links.add(spec);
            }
        }
private static final voidgatherMapLinks(java.util.ArrayList links, android.text.Spannable s)

        String string = s.toString();
        String address;
        int base = 0;

        while ((address = WebView.findAddress(string)) != null) {
            int start = string.indexOf(address);

            if (start < 0) {
                break;
            }

            LinkSpec spec = new LinkSpec();
            int length = address.length();
            int end = start + length;
            
            spec.start = base + start;
            spec.end = base + end;
            string = string.substring(end);
            base += end;

            String encodedAddress = null;

            try {
                encodedAddress = URLEncoder.encode(address,"UTF-8");
            } catch (UnsupportedEncodingException e) {
                continue;
            }

            spec.url = "geo:0,0?q=" + encodedAddress;
            links.add(spec);
        }
private static final java.lang.StringmakeUrl(java.lang.String url, java.lang.String[] prefixes, java.util.regex.Matcher m, android.text.util.Linkify$TransformFilter filter)

        if (filter != null) {
            url = filter.transformUrl(m, url);
        }

        boolean hasPrefix = false;
        
        for (int i = 0; i < prefixes.length; i++) {
            if (url.regionMatches(true, 0, prefixes[i], 0,
                                  prefixes[i].length())) {
                hasPrefix = true;

                // Fix capitalization if necessary
                if (!url.regionMatches(false, 0, prefixes[i], 0,
                                       prefixes[i].length())) {
                    url = prefixes[i] + url.substring(prefixes[i].length());
                }

                break;
            }
        }

        if (!hasPrefix) {
            url = prefixes[0] + url;
        }

        return url;
private static final voidpruneOverlaps(java.util.ArrayList links)

        Comparator<LinkSpec>  c = new Comparator<LinkSpec>() {
            public final int compare(LinkSpec a, LinkSpec b) {
                if (a.start < b.start) {
                    return -1;
                }

                if (a.start > b.start) {
                    return 1;
                }

                if (a.end < b.end) {
                    return 1;
                }

                if (a.end > b.end) {
                    return -1;
                }

                return 0;
            }

            public final boolean equals(Object o) {
                return false;
            }
        };

        Collections.sort(links, c);

        int len = links.size();
        int i = 0;

        while (i < len - 1) {
            LinkSpec a = links.get(i);
            LinkSpec b = links.get(i + 1);
            int remove = -1;

            if ((a.start <= b.start) && (a.end > b.start)) {
                if (b.end <= a.end) {
                    remove = i + 1;
                } else if ((a.end - a.start) > (b.end - b.start)) {
                    remove = i + 1;
                } else if ((a.end - a.start) < (b.end - b.start)) {
                    remove = i;
                }

                if (remove != -1) {
                    links.remove(remove);
                    len--;
                    continue;
                }

            }

            i++;
        }