Highlight multiple words in a string using SpannableString - android

I'm using a SpannableString to underline certain words, however, I realized the code I have only highlights the first word if there are multiple words. Not exactly sure how to accomplish highlighting multiple words:
String keyword = "test";
String text = "This is a test to underline the three test words in this test";
SpannableString output = new SpannableString(text);
if (text.indexOf(keyword) > -1)
{
int keywordIndex = text.indexOf(keyword);
int keywordLength = keyword.length();
int start = keywordIndex;
int end = keywordIndex + (keywordLength);
output.setSpan(new UnderlineSpan(), start, end, 0);
}
I was thinking I could split the text at every space and loop through it, but wasn't sure if there was a better way.
I do have this code to highlight multiple words using a regular expression, however, I'm try to avoid regular expressions since it's in an Android app and I'm using it in a ListView and I'm told they are very expensive. Also this code I have only highlight whole words, so using the example text above, if the word "protest" was in the sentence, it wouldn't get highlighted using this code:
Matcher matcher = Pattern.compile("\\b(?:test")\\b").matcher(text);
while (matcher.find())
{
output.setSpan(new UnderlineSpan(), matcher.start(), matcher.end(), 0);
}

Related

TextView with anchor and raw links (SpannableString issue)

In my textview, I want both anchors and raw links to be clickable. I'm letting TextView.setAutoLinkMask(Linkify.ALL) handle all of the raw links and then retrieving the spans and setting them with SpannableString for all of the anchors.
I would like to be able to 'linkify' the anchors in my custom TextView implementation (extends TextView) in the setText(CharSequence text, BufferType type) call. Everything seems to be working properly except for the setSpan() call (end, start, and span are all correct). At the end of setText(...), I'm assigning the global CharSequence var to the new SpannableString. When setText() is called from my adapter, the spans identified in Object[]spans are not linked.
#Override
public void setText(CharSequence text, BufferType type) {
Spanned html = Html.fromHtml(text.toString().replace("\n", "<br />"));
Object[] spans = html.getSpans(0, html.length(), URLSpan.class);
SpannableString s = new SpannableString(html);
for (int i = 0; i < spans.length; i++) {
URLSpan span = (URLSpan) spans[i];
int end = html.getSpanEnd(span);
int start = html.getSpanStart(span);
int flags = html.getSpanFlags(span);
Log.i(LOG_TAG, "span: " + span.getURL() + "\nstart: " + start + "\nend: " + end);
s.setSpan(span, start, end, flags);
}
mText = s;
}
I found a slight workaround to this issue in the code listed below. In this implementation, I'm setting the spans in the adapter instead of the CustomTextView. This method works fine but doesn't entirely fit my needs because my TextView is used as an ExpandableTextView, meaning that there are 2 sets of texts (trimmed and full) and often times the trimmed version is returned (which is fine in typical scenarios, except that I want to add tags to the full text). This implementation often crashes because the spans that were originally identified were for the fullText and getText() is returning the trimmedText. So I think it'll be necessary for me to be able to do this in my custom TextView's setText(). BUT, the below method does work granted that trimmedText and fullText are the same length.
Spanned html = Html.fromHtml(postText.replace("\n", "<br />"));
Object[] spans = html.getSpans(0, html.length(), URLSpan.class);
h.content.setAutoLinkMask(Linkify.ALL);
h.content.setMovementMethod(LinkMovementMethod.getInstance());
h.content.setText(html);
h.content.setLinkTextColor(Color.rgb(136, 194, 226));
h.content.setVisibility(View.VISIBLE); // Need this otherwise the view disappears....
SpannableString ss = (SpannableString) h.content.getText();
for (int i = 0; i < spans.length; i++) {
URLSpan span = (URLSpan) spans[i];
int end = html.getSpanEnd(span);
int start = html.getSpanStart(span);
int flags = html.getSpanFlags(span);
ss.setSpan(span, start, end, flags);
}
Here's how I solved my problem:
At the point of my problem, I had already parsed through the content and added anchors (HTML links that would launch an activity when clicked) to my tags (# and #). I also wanted to make raw (e.g., www.google.com) clickable, so I tried setting my TextView to setAutoLinkMask(Linkify.ALL) but this broke the anchor links.
So this is what I did:
SpannableStringBuilder ssb =
new SpannableStringBuilder(Html.fromHtml
(this.content.replace("\n", "<br />")));
Pattern urlPattern = android.util.Patterns.WEB_URL;
Linkify.addLinks(ssb, urlPattern, "youractivityhere://");
myTextView.setText(ssb);
Basically I'm using a regex matcher to find any URLs within the String and then add a link using Linkify.addLinks(...).
I was making the problem way more difficult than needed.

How to Replace multiple string on a TexView for SpannableStrings?

I am looking for a way to find different strings on a TextView and replace them with styled SpannableStrings.
I found this code in How to use SpannableString with Regex in android? that does just that for a single string:
public class SpanTest extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
String dispStr = "This has the string ABCDEF in it \nSo does this :ABCDEF - see!\nAnd again ABCD here";
TextView tv = (TextView) findViewById(R.id.textView1);
tv.setText(dispStr);
changeTextinView(tv, "ABC", Color.RED);
}
private void changeTextinView(TextView tv, String target, int colour) {
String vString = (String) tv.getText();
int startSpan = 0, endSpan = 0;
Spannable spanRange = new SpannableString(vString);
while (true) {
startSpan = vString.indexOf(target, endSpan);
ForegroundColorSpan foreColour = new ForegroundColorSpan(colour);
// Need a NEW span object every loop, else it just moves the span
if (startSpan < 0)
break;
endSpan = startSpan + target.length();
spanRange.setSpan(foreColour, startSpan, endSpan,
Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
}
tv.setText(spanRange);
}
}
This works great but I'm not sure how to adapt it to use if with multiple strings.
I tried to re-implement it using SpannableStringBuilder.replace so I can run the method multiple times while keeping the previous style but have failed.
Any Ideas?
Thanks!
This works great but I'm not sure how to adapt it to use if with multiple strings.
Off the cuff...
Step #1: Change changeTextinView() to take a SpannableString as the first parameter, instead of a TextView.
Step #2: Modify onCreate() to create a SpannableString from dispStr and pass that to changeTextinView(), then take the SpannableString and pass it to setText() on the TextView.
At this point, it should work as it did before, except that you will be in position to do:
Step #3: Call changeTextinView() several times in succession, once per string.
Things will get somewhat messy if there is overlap (e.g., you want to format ABCDEF one way and CDE another way), but I am hoping that is not the case for you.

Highlight a particular word in a String dynamically

I want to highlight a particular word in a text view ( more specifically similar to a twitter feed). The word may occur multiple times. Below I will post a sample sentence from twitter.
" Mumbai Master Blaster! #Sachin. Greatest players of all times. The legend of cricket #sachin. "
Here I want to highlight the word " #Sachin " with a particular color. Also please note that we don't know how many times this word could get repeated in the whole string. Could anyone help me to solve this issue.
Use next code:
public CharSequence linkifyHashtags(String text) {
SpannableStringBuilder linkifiedText = new SpannableStringBuilder(text);
Pattern pattern = Pattern.compile("#\\w");
Matcher matcher = pattern.matcher(text);
while (matcher.find()) {
int start = matcher.start();
int end = matcher.end();
String hashtag = text.substring(start, end);
ForegroundColorSpan span = new ForegroundColorSpan(Color.BLUE);
linkifiedText.setSpan(span, 0, hashtag.length(), 0);
}
return linkifiedText;
}

Android - Highlight a Word In a TextView?

I have a database search query which search in the database for a word entered by the user and return a Cursor.
In my ListActivity, I have a ListView which will hold the items (the Cursor items). The ListView items layout is basically a TextView. I mean, the ListView will be a list of TextView's.
What I want is to highlight the search term wherever it appears in the TextView. I mean by highlighting: different color or different background color or anything makes it different than the rest of the text.
Is this possible? and how?
Update:
cursor = myDbHelper.search(term); //term: a word entered by the user.
cursor.moveToFirst();
String[] columns = {cursor.getColumnName(1)};
int[] columnsLayouts = {R.id.item_title}; //item_title: the TextView holding the one raw
ca = new SimpleCursorAdapter(this.getBaseContext(), R.layout.items_layout, cursor,columns , columnsLayouts);
lv = getListView();
lv.setAdapter(ca);
For #Shailendra: The search() method will return some titles. I want to highlight the words in those titles that matches the term word. I hope this is clear now.
insert HTML code for color around word and set it to your textView .
like
String newString = oldString.replaceAll(textToHighlight, "<font color='red'>"+textToHighlight+"</font>");
textView.setText(Html.fromHtml(newString));
TextView textView = (TextView)findViewById(R.id.mytextview01);
//use a loop to change text color
Spannable WordtoSpan = new SpannableString("partial colored text");
WordtoSpan.setSpan(new ForegroundColorSpan(Color.BLUE), 2, 4, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
textView.setText(WordtoSpan);
The numbers 2 and 4 are start/stop indexes for the coloring of the text, in this example "rti" would be colored.
So you would basically just find the starting index of your searching word in the title:
int startIndex = titleText.indexOf(term);
int stopIndex = startIndex + term.length();
and then replace the numbers 2 and 4 with the indexes and "partial colored text" with your title string.
source: https://stackoverflow.com/a/10279703/2160827
More Easy Way
You can use Spannable class for highlighting/formatting part of Text.
textView.setText("Hello, I am Awesome, Most Awesome"); // set text first
setHighLightedText(textView, "a"); // highlight all `a` in TextView
Here is the method.
/**
* use this method to highlight a text in TextView
*
* #param tv TextView or Edittext or Button (or derived from TextView)
* #param textToHighlight Text to highlight
*/
public void setHighLightedText(TextView tv, String textToHighlight) {
String tvt = tv.getText().toString();
int ofe = tvt.indexOf(textToHighlight, 0);
Spannable wordToSpan = new SpannableString(tv.getText());
for (int ofs = 0; ofs < tvt.length() && ofe != -1; ofs = ofe + 1) {
ofe = tvt.indexOf(textToHighlight, ofs);
if (ofe == -1)
break;
else {
// set color here
wordToSpan.setSpan(new BackgroundColorSpan(0xFFFFFF00), ofe, ofe + textToHighlight.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
tv.setText(wordToSpan, TextView.BufferType.SPANNABLE);
}
}
}
You can check this answer for clickable highlighted text.
I know it's old question but i have created a method to highlight a repeated-word in string\paragraph.
private Spannable highlight(int color, Spannable original, String word) {
String normalized = Normalizer.normalize(original, Normalizer.Form.NFD)
.replaceAll("\\p{InCombiningDiacriticalMarks}+", "");
int start = normalized.indexOf(word);
if (start < 0) {
return original;
} else {
Spannable highlighted = new SpannableString(original);
while (start >= 0) {
int spanStart = Math.min(start, original.length());
int spanEnd = Math.min(start+word.length(), original.length());
highlighted.setSpan(new ForegroundColorSpan(color), spanStart,
spanEnd, Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
start = normalizedText.indexOf(word, spanEnd);
}
return highlighted;
}
}
usage:
textView.setText(highlight(primaryColor, textAll, wordToHighlight));
Based on the previous answers I developed the following function, you can copy/paste it
private void highlightMask(TextView textView, String text, String mask) {
boolean highlightenabled = true;
boolean isHighlighted = false;
if (highlightenabled) {
if (!TextUtils.isEmpty(text) && !TextUtils.isEmpty(mask)) {
String textLC = text.toLowerCase();
mask = mask.toLowerCase();
if (textLC.contains(mask)) {
int ofe = textLC.indexOf(mask, 0);
Spannable wordToSpan = new SpannableString(text);
for (int ofs = 0; ofs < textLC.length() && ofe != -1; ofs = ofe + 1) {
ofe = textLC.indexOf(mask, ofs);
if (ofe == -1) {
break;
} else {
// set color here
wordToSpan.setSpan(new BackgroundColorSpan(0xFFFFFF00), ofe, ofe + mask.length(),
Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
textView.setText(wordToSpan, TextView.BufferType.SPANNABLE);
isHighlighted = true;
}
}
}
}
}
if (!isHighlighted) {
textView.setText(text);
}
}
I haven't done it but this looks promising:
http://developer.android.com/reference/android/text/SpannableString.html
http://developer.android.com/guide/topics/resources/string-resource.html
public final void setText (CharSequence text)
Since: API Level 1 Sets the string value of the TextView. TextView
does not accept HTML-like formatting, which you can do with text
strings in XML resource files. To style your strings, attach
android.text.style.* objects to a SpannableString, or see the
Available Resource Types documentation for an example of setting
formatted text in the XML resource file.
http://developer.android.com/reference/android/widget/TextView.html
Try this library Android TextHighlighter.
Implementations
TextView.setText() gets a parameter as Spannable not only CharacterSequence. SpannableString has a method setSpan() which allows applying styles.
See list of direct subclass form CharacterStyle https://developer.android.com/reference/android/text/style/CharacterStyle.html
example of giving background color and foreground color for word "Hello" in "Hello, World"
Spannable spannable = new SpannableString("Hello, World");
// setting red foreground color
ForegroundSpan fgSpan = new ForegroundColorSpan(Color.red);
// setting blue background color
BackgroundSpan bgSpan = new BackgroundColorSPan(Color.blue);
// setSpan requires start and end index
// in our case, it's 0 and 5
// You can directly set fgSpan or bgSpan, however,
// to reuse defined CharacterStyle, use CharacterStyle.wrap()
spannable.setSpan(CharacterStyle.wrap(fgSpan), 0, 5, 0);
spannable.setSpan(CharacterStyle.wrap(bgSpan), 0, 5, 0);
// apply spannableString on textview
textView.setText(spannable);
You do so in xml strings if your strings are static
<string name="my_text">This text is <font color='red'>red here</font></string>
I know this thread is old, but just in case anyone is looking to highlight strings in a textview, I have created a library that does exactly this. This is my first answer to a question on stack overflow, as I have just joined, hopefully it's formatted properly and relevant. It uses SpannableString and will locate all occurrences of a string you specify. Additionally, a custom ClickableSpan is built in giving you the option to set up listeners for text clicked if desired.
Linker
Lightweight android library for highlighting Strings inside of a textview (ignoring case), with optional callbacks.
Language: Java
MinSDK: 17
An image of it's functionality and all of the code can be found
here.
JavaDocs
To bring into your android project implement the artifact:
In the Project level build.gradle
allprojects {
repositories {
...
maven { url 'https://jitpack.io' }
}
}
In the App level build.gradle
dependencies {
implementation 'com.github.Gaineyj0349:Linker:1.2'
}
How to use:
1 - Construct a Linker object with a textview:
Linker linker = new Linker(textView);
2 - Add an array or a list of strings to be highlighted within the textview's text:
ArrayList<String> list = new ArrayList<>();
list.add("hello");
list.add("world");
linker.addStrings(list);
AND/OR
String[] words = new String[]{"One", "Two", "Three"};
linker.addStrings(words);
3 - Add a callback: (this is optional):
linker.setListener(new LinkerListener() {
#Override
public void onLinkClick(String charSequenceClicked) {
// charSequenceClicked is the word that was clicked
Toast.makeText(MainActivity.this, charSequenceClicked, Toast.LENGTH_SHORT).show();
}
});
4 - Call the linker's update method to commit customization and rollout the setup.:
linker.update();
You always have the option to add Strings to the linker object, just make sure you call the update method after to refresh the spans.
linker.addStrings("yoda");
linker.update();
If you need a fresh slate with same linker object just call
linker.clearLinksList()
You can customize the links also:
1 - Customize all the link colors:
linker.setAllLinkColors(Color.BLUE);
2 - Customize link underlines:
linker.setAllLinkUnderline(false);
3 - If you wish to customize a color or underline setting for a certain string (note the string must already be added to the linker):
linker.setLinkColorForCharSequence("world", Color.MAGENTA);
linker.setUnderlineModeForCharSequence("world", true);
4 - If you wish to use different setups for every word then you can also give the linker object a list or array of LinkProfiles:
ArrayList<LinkProfile> profiles = new ArrayList<>();
profiles.add(new LinkProfile("hello world",
Color.GREEN, false));
profiles.add(new LinkProfile("goodbye cruel world",
Color.RED, false));
profiles.add(new LinkProfile("Whoa awesome!",
Color.CYAN, true));
linker.addProfiles(profiles);
Just remember to call .update() after any additions to the linker object.
Note that the library will take care of subtleties like adding two of the same words, or same parts of a word. For example if "helloworld" and "hello" are two of the words added to the linker, "helloworld" will be given preference over "hello" when they are in the same span of characters. The linker will sort according to larger words first and trace all spans as it links them - avoiding the issue of duplication as well as intersecting spans.
Licensed under MIT license .

Can I change TextView link text after using Linkify?

Is is possible to change TextView text after using Linkify to create links? I have something where I want the url to have two fields, a name and id, but then I just want the text to display the name.
So I start off with a textview with text that includes both name and id, and linkify to create the appropriate links with both fields. But for the display, I don't want to show the id.
Is this possible?
It's kind of a pain but yes. So Linkify basically does a few things. First it scans the contents of the textview for strings that match that of a url. Next it creates UrlSpan's and ForegroundColorSpan's for those sections that match it. Then it sets the MovementMethod of the TextView.
The important part here are the UrlSpan's. If you take your TextView and call getText(), notice it returns a CharSequence. It's most likely some sort of Spanned. From the Spanned you can ask, getSpans() and specifcally the UrlSpans. Once you know all those spans you can than loop through the list and find and replace the old span objects with your new span objects.
mTextView.setText(someString, TextView.BufferType.SPANNABLE);
if(Linkify.addLinks(mTextView, Linkify.ALL)) {
//You can use a SpannableStringBuilder here if you are going to
// manipulate the displayable text too. However if not this should be fine.
Spannable spannable = (Spannable) mTextView.getText();
// Now we go through all the urls that were setup and recreate them with
// with the custom data on the url.
URLSpan[] spans = spannable.getSpans(0, spannable.length, URLSpan.class);
for (URLSpan span : spans) {
// If you do manipulate the displayable text, like by removing the id
// from it or what not, be sure to keep track of the start and ends
// because they will obviously change.
// In which case you may have to update the ForegroundColorSpan's as well
// depending on the flags used
int start = spannable.getSpanStart(span);
int end = spannable.getSpanEnd(span);
int flags = spannable.getSpanFlags(span);
spannable.removeSpan(span);
// Create your new real url with the parameter you want on it.
URLSpan myUrlSpan = new URLSpan(Uri.parse(span.getUrl).addQueryParam("foo", "bar");
spannable.setSpan(myUrlSpan, start, end, flags);
}
mTextView.setText(spannable);
}
Hopefully that makes sense. Linkify is just a nice tool to setup the correct Spans. Spans just get interpreted when rendering text.
Greg's answer doesn't really answer the original question. But it does contain some insight as to where to start. Here's a function that you can use. It assumes that you have Linkified your textview prior to this call. It's in Kotlin, but you can get the gist of it if you are using Java.
In short, it builds a new Spannable with your new text. During the build, it copies over the url/flags of the URLSpans that the Linkify call created previously.
fun TextView.replaceLinkedText(pattern: String) { // whatever pattern you used to Linkify textview
if(this.text !is Spannable) return // no need to process since there are no URLSpans
val pattern = Pattern.compile(pattern, Pattern.CASE_INSENSITIVE)
val matcher = pattern.matcher(this.text)
val linkifiedText = SpannableStringBuilder()
var cursorPos = 0
val spannable = this.text as Spannable
while (matcher.find()) {
linkifiedText.append(this.text.subSequence(cursorPos, matcher.start()))
cursorPos = matcher.end()
val span = spannable.getSpans(matcher.start(), matcher.end(), URLSpan::class.java).first()
val spanFlags = spannable.getSpanFlags(span)
val tag = matcher.group(2) // whatever you want to display
linkifiedText.append(tag)
linkifiedText.setSpan(URLSpan(span.url), linkifiedText.length - tag.length, linkifiedText.length, spanFlags)
}
this.text = linkifiedText
}

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