Android loop through string to color specific words

Question

I have a string that has specific words I want to color. Those words are the one's that start with #.

    if(title.contains("#")){

        SpannableString WordtoSpan = new SpannableString(title);   

        int idx = title.indexOf("#");
        if (idx >= 0) {

            Pattern pattern = Pattern.compile("[ ,\\.\\n]");
            Matcher matcher = pattern.matcher(title);
            int wordEnd = matcher.find(idx)? matcher.start() : -1;

            if (wordEnd < 0) {
                wordEnd = title.length();
            }
            WordtoSpan.setSpan(new ForegroundColorSpan(Color.BLUE),
                        idx,
                        wordEnd,
                        Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
        }           

        holder.txtTitle.setText(WordtoSpan);
    } else {
        holder.txtTitle.setText(title);
    }

Now lets take for example this string Bold part is for example the colored words.

I love cheese #burgers, and with #ketchup.

^ This is my current thing with my code. What I want is to color every # word, not just first one.

ex. It'll be like

I love cheese #burgers, and with #ketchup.

I think I need to loop? But couldn't get it clearly and working x.x

Update: Latest try. List becomes blank.

    SpannableString WordtoSpan = new SpannableString(title);

    int end = 0;

    Pattern pattern = Pattern.compile("[ ,\\.\\n]");
    Matcher matcher = pattern.matcher(title);

    int i = title.indexOf("#");

    for (i = 0; i < title.length(); i++) {
    if (i >= 0) {

        int wordEnd = matcher.find(i)? matcher.start() : -1;

        if (wordEnd < 0) {
            wordEnd = title.length();
        }
        WordtoSpan.setSpan(new ForegroundColorSpan(Color.BLUE),
                    i,
                    wordEnd,
                    Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

        i = end;
    }    

    holder.txtTitle.setText(WordtoSpan);
    }

score 7 · Answer 1 · edited May 23 '17 at 10:30

I had provided this answer earlier here - https://stackoverflow.com/a/20179879/3025732

String text = "I love chicken #burger , cuz they are #delicious";
//get the text from TextView

Pattern HASHTAG_PATTERN = Pattern.compile("#(\\w+|\\W+)");
Matcher mat = HASHTAG_PATTERN.matcher(text);

while (mat.find()) {
  String tag = mat.group(0);

  //String tag will contain the hashtag
  //do operations with the hashtag (change color)
}

[EDIT]

I've modified the code and done it according to what you need:

SpannableString hashText = new SpannableString(text.getText().toString());
Matcher matcher = Pattern.compile("#([A-Za-z0-9_-]+)").matcher(hashText);
while (matcher.find())
{
     hashText.setSpan(new ForegroundColorSpan(Color.BLUE), matcher.start(), matcher.end(), 0);
}
text.setText(hashText);

Here's a screenshot of it:

enter image description here

But I dont know how to "do the operation", I'm a beginner, trying to develop with my bro. So how to supply end, start etc.. — John Jared, Nov 27 '13 at 19:25
@JohnJared Please check my updated answer with the code sample you wanted — Joel Fernandes, Nov 27 '13 at 19:51

Vikram · Accepted Answer · 2013-11-27T19:14:33.403

4

I'm surprised that no one has mentioned this:

// String you want to perform on
String toChange = "I love cheese #burgers, and with #ketchup.";

// Matches all characters, numbers, underscores and dashes followed by '#'
// Does not match '#' followed by space or any other non word characters
toChange = toChange.replaceAll("(#[A-Za-z0-9_-]+)", 
                         "<font color='#0000ff'>" + "$0" +  "</font>");

// Encloses the matched characters with html font tags

// Html#fromHtml(String) returns a Spanned object
holder.txtTitle.setText(Html.fromHtml(toChange));

#0000ff ==>> Color.BLUE

Screenshot:

enter image description here

edited Nov 27 '13 at 19:14

answered Nov 27 '13 at 18:59

Vikram

51,313
11
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@JohnJared Added a screenshot above. Could the problem be somewhere else in your code? – Vikram Nov 27 '13 at 19:15
Umm, found out why. Cuz in my app I have arabic letter with # thats i why, but when I changed arabic to eng they worked. How can I make it color arabic words too? – John Jared Nov 27 '13 at 19:21
أ ب ت ث ج ح خ د ذ ل ز ر ع غ ف ق س ش ص ض ط ظ م ر ه ن و ي – John Jared Nov 27 '13 at 19:23
I should wait 16 hrs, after 16 hrz ill give u the +50, thanks! – John Jared Nov 27 '13 at 19:27
@JohnJared You are welcome. Thanks for the accept. Here's another answer of mine following a slightly different approach, but accomplishing the same output: [How to color text using Regex in android](http://stackoverflow.com/a/17849313/2558882). – Vikram Nov 27 '13 at 19:39
@JohnJared Just wondering: was there something wrong with my answer? – Vikram Nov 29 '13 at 16:01
1

Nope, but I gave that person +50 by mistake x.x sorry. I'll start another bounty on the next question I ask and I will reward you it. I am very sorry – John Jared Nov 30 '13 at 15:24
@JohnJared Hey, this has happened to me before: [here](http://stackoverflow.com/questions/18535473/activity-has-leaked-window-that-was-originally-added-here-other-issues-concer/18564353#18564353)!! Lol. If it was a mistake, no harm, no foul. Please don't start another question to reward me. I was merely confused as to whether my answer was alright. – Vikram Nov 30 '13 at 16:42
check this out, http://stackoverflow.com/questions/20427398/android-matcher-and-patter-cut-up-from-the-link – John Jared Dec 06 '13 at 15:17
@JohnJared Saw your comment too late :) – Vikram Dec 07 '13 at 19:44
Hello, I am using this code `" + "$0" + "` . But in my case ex is "#abc xyz". But it is coloring only #abc. How to consider whole string "#abc xyz". – Shyamaly Lakhadive Jan 22 '21 at 09:34
@ShyamalyLakhadive I think `Joel Fernandes's` answer outlines a better approach. You'll still need to come up with a way to isolate the substring that needs to be colored - either by using regex or by some calculation. – Vikram Jan 22 '21 at 20:47
@Vikram I tried with different regular expression but either it color complete text present in edittext or not a single word. I tried many regular expression. – Shyamaly Lakhadive Jan 24 '21 at 03:53

score 1 · Answer 3 · edited May 23 '17 at 12:26

1

You need to loop through your matches. There is a previous post you can have a look at here:

Finding Multiple Integers Inside A String Using Regex

edited May 23 '17 at 12:26

Community

1
1

answered Nov 25 '13 at 12:38

Anders Ludvigsson

11
2

It's fine to find them(I can use .split("#"), but how to find them **and** color them inside the string at the same time? – John Jared Nov 25 '13 at 12:50
if(title.contains("#")){ Matcher matcher = pattern.matcher(title); while ( matcher.find() ) { //do ForegroundcolorSpan etc } } – Anders Ludvigsson Nov 27 '13 at 13:53

Eldhose M Babu · Answer 4 · 2013-11-27T18:00:20.043

Check following example :

String title = "Your #complete sentence #testing #test.";
printUsingNormal(title);
printUsingRegex(title);

private static void printUsingRegex(String title) {
    Pattern pattern = Pattern.compile("[ ,\\.\\n]");

    int start = 0;
    int end = 0;
    Matcher matcher = pattern.matcher(title);
    while (end >= 0 && end < title.length()) {
        start = title.indexOf('#', start);
        if (start > 0) {
            end = matcher.find(start) ? matcher.start() : -1;
            if (end > 0) {
                System.out.println("Word : " + title.substring(start, end)
                        + " Start : " + start + " End : " + end);
                start = end;
            }
        } else {
            break;
        }
    }
}

private static void printUsingNormal(String title) {
    int start = 0;
    for (int i = 0; i < title.length(); i++) {
        char c = title.charAt(i);
        if (c == '#') {
            start = i; // Got the starting hash
            int end = title.indexOf(' ', i + 1); // Finding the next space.
            if (end > 0) {
                System.out.println("Word : " + title.substring(start, end)
                        + " Start : " + start + " End : " + end);
                i = end;
            } else {
                end=title.length()-1;
                System.out.println("Word : " + title.substring(start, end)
                        + " Start : " + start + " End : " + end);
                i = end;
            }
        }
    }
}

Please find my updated answer above. which uses both regex and direct way. — Eldhose M Babu, Nov 27 '13 at 17:58
Umm, now I'm confused. How do I use it now? Can you do the regex way with the old answer ?(so regex+the loop int i) — John Jared, Nov 27 '13 at 18:21
please check my latest try in my answer's update. See what I mean, and what Am I missing. — John Jared, Nov 27 '13 at 18:35

score 0 · Answer 5 · answered Nov 25 '13 at 12:58

0

Use while(), this is the snippet for setting the background color of text searched in android native messenger, you can try the same in your code.

answered Nov 25 '13 at 12:58

VenomVendor

15,064
13
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check my updated question, I tried using while. Now nothing appears on the list. – John Jared Nov 25 '13 at 14:25

Android loop through string to color specific words

5 Answers5