Develop Reference

How do I change color of a certain part of my textview?

I am using 2 parts in a textview, 1st part is date another is name and email.
They are both referenced in the same textview. I would like to change the color of the date to give it a different visual it from name and email. is it possible to do this without actually adding a whole new textview for name and email?
Here's my code so far:
String nameandemail;
holder.mytext.setText(String.valueOf(dateFormat.format(new Date(msg.getDate())) + " " + nameandemail + ": "));
How do I make it such that I can set the color of date with
holder.mytext.setTextColor(Color.white) and for the nameandemail string something like green?
Thanks!

You can Use spans.
final SpannableStringBuilder sb = new SpannableStringBuilder("your text here");
// Set text color to some RGB value
final ForegroundColorSpan fcs = new ForegroundColorSpan(Color.rgb(158, 158, 158));
// Make text bold
final StyleSpan bss = new StyleSpan(android.graphics.Typeface.BOLD);
// Set the text color for first 6 characters
sb.setSpan(fcs, 0, 6, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
// make them also bold
sb.setSpan(bss, 0, 4, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
textView.setText(sb);
You can also use html like below
myTextView.setText(Html.fromHtml(text + "<font color=white>" + some_text + "</font><br><br>"
+ some_text));

you could define a String in your strings.xml file
<string name="test2"><font color=\'#FFFFFF\'>%1$s</font> -- <font color=\'#00FF00\'>%2$s</font></string>
and then programmatically
TextView tv = (TextView) findViewById(R.id.test);
tv.setText(Html.fromHtml(getString(R.string.test2, String.valueOf(dateFormat.format(new Date(msg.getDate())), nameandemail)));

My recommendation would be to use Spannable.
Here is a short utils method I wrapped up for you to use. You simply need to pass your TextView, your full text and the single part to be re-colored from the full text.
You can place this method to a Utils class and call it whenever you want, or keep it in a single Activity or Fragment(or wherever else) if you use it in a single class:
public static void colorText(TextView view, final String fullText, final String whiteText) {
if (fullText.length() < whiteText.length()) {
throw new IllegalArgumentException("'fullText' parameter should be longer than 'whiteText' parameter ");
}
int start = fullText.indexOf(whiteText);
if (start == -1) {
return;
}
int end = start + whiteText.length();
SpannableStringBuilder finalSpan = new SpannableStringBuilder(fullText);
// finalSpan.setSpan(new ForegroundColorSpan(ContextCompat.getColor(view.getContext(),R.color.your_own_color_code)), start, end, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
finalSpan.setSpan(new ForegroundColorSpan(Color.WHITE), start, end, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
view.setText(finalSpan);
}

Android - Html.fromHtml handle background color

I have html text that I need to display in TextView. The html may look like this -
<font color="#AFEEEE"><font style="background-color: rgb(255,140,0);">Text with background and color</font></font>
Html.fromHtml doesn't support any attribute other than color for font tag. But we absolutely must show the background. I could write a custom tag handler but the attributes are not passed in, only the tag is passed in.
What is the best way to achieve this ?
NOTE : Cant use Webview.
I tried the code below. If I set raw on the text, it works, but if i process it further and pass it to Html.fromHtml, it doesnt show the background.
public static final String sText =
"Background on <font style=\"background-color: rgb(255,255,0);\">pa</font>rt text only";
Pattern pattern = Pattern.compile(BACKGROUND_PATTERN);
Matcher matcher = pattern.matcher(sText);
SpannableString raw = new SpannableString(sText);
BackgroundColorSpan[] spans =
raw.getSpans(0, raw.length(), BackgroundColorSpan.class);
for (BackgroundColorSpan span : spans) {
raw.removeSpan(span);
}
while (matcher.find()) {
raw.setSpan(new BackgroundColorSpan(0xFF8B008B),
matcher.start(2), matcher.start(2) + matcher.group(2).length(),
Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
}
sText = raw.toString();
final Spanned convertedHtml =
Html.fromHtml(sText, ig, new myTagHandler());

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
String str = "<span style=\"background-color:#f3f402;\">" + TEXT TO HIGHLIGHT + "</span>";
textView.setText(Html.fromHtml(str, Html.FROM_HTML_MODE_LEGACY));
} else {
String str = "<font color='#f3f402'>" + TEXT TO HIGHLIGHT + "</font>";
textView.setText(Html.fromHtml(str));
}
More - https://stackoverflow.com/a/46035856/3625510

Add your own BackgroundColorSpan as you see fit.
Here is some code that sets such a span on all occurrences of a search term within a TextView:
private void searchFor(String text) {
TextView prose=(TextView)findViewById(R.id.prose);
Spannable raw=new SpannableString(prose.getText());
BackgroundColorSpan[] spans=raw.getSpans(0,
raw.length(),
BackgroundColorSpan.class);
for (BackgroundColorSpan span : spans) {
raw.removeSpan(span);
}
int index=TextUtils.indexOf(raw, text);
while (index >= 0) {
raw.setSpan(new BackgroundColorSpan(0xFF8B008B), index, index
+ text.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
index=TextUtils.indexOf(raw, text, index + text.length());
}
prose.setText(raw);
}
So, find your beginning and ending points, create a BackgroundSpan with your desired color, and use setSpan() to apply it.
Note that this assumes that only part of your text needs the background color. If the entire TextView needs the color, go with njzk2's suggestion, and just apply the color to the whole TextView.

SpannableStringBuilder to create String with multiple fonts/text sizes etc Example?

I need to create a String placed in a TextView that will display a string like this:
First Part Not Bold BOLD rest not bold
So I want to know how I could use SpannableStringBuilder to do this?
I could use three TextEdit to accomplish this but I would like to use best solution.

First Part Not Bold BOLD rest not bold
You can do this either as #Rajesh suggested or by this.
String normalBefore= "First Part Not Bold ";
String normalBOLD= "BOLD ";
String normalAfter= "rest not bold";
String finalString= normalBefore+normalBOLD+normalAfter;
Spannable sb = new SpannableString( finalString );
sb.setSpan(new StyleSpan(android.graphics.Typeface.BOLD), finalString.indexOf(normalBOLD)+ normalBOLD.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); //bold
sb.setSpan(new AbsoluteSizeSpan(intSize), finalString.indexOf(normalBOLD)+ normalBOLD.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);//resize size
to show this in TextView
textview.setText(sb, TextView.BufferType.SPANNABLE);

The accepted answer is fine (and I upvoted it), but it fails to use the SpannableStringBuilder as the submitter requested. As I had a case where the Builder made the most sense, here is the code for that (with a bonus use of also changing the color of the text if that is helpful to others). Note that you could also provide the initial string to the SpannableStringBuilder constructor, but I set it here to use "append" to be clear that you can append a lot before your desired "bold" text and then just record the start as shown. I would suspect that this is also faster code than the accepted answer.
SpannableStringBuilder longDescription = new SpannableStringBuilder();
longDescription.append("First Part Not Bold ");
int start = longDescription.length();
longDescription.append("BOLD");
longDescription.setSpan(new ForegroundColorSpan(0xFFCC5500), start, longDescription.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
longDescription.setSpan(new StyleSpan(android.graphics.Typeface.BOLD), start, longDescription.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
longDescription.append(" rest not bold");

If you are using Kotlin you can do the following using the android-ktx library
val s = SpannableStringBuilder()
.append("First Part Not Bold ")
.bold { append("BOLD") }
.append("Rest not bold")
The bold is an extension function on SpannableStringBuilder. You can see the documentation here for a list of operations you can use.
Another example:
val s = SpannableStringBuilder()
.color(green, { append("Green text ") })
.append("Normal text ")
.scale(0.5, { append("Text at half size " })
.backgroundColor(green, { append("Background green") })
Where green is a resolved RGB color.
It is even possible to nest spans so you end up with an embedded DSL:
bold { underline { italic { append("Bold and underlined") } } }
You will need the following in your app module level build.gradle for it to work:
repositories {
google()
}
dependencies {
implementation "androidx.core:core-ktx:1.2.0"
}

From API 21 SpannableStringBuilder includes a simple method to do this. Here is a solution example:
SpannableStringBuilder builder= new SpannableStringBuilder();
StyleSpan boldSpan = new StyleSpan(android.graphics.Typeface.BOLD);
builder.append("First Part Not Bold ")
.append("BOLD ", boldSpan, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)
.append("rest not bold");
Kotlin version:
val builder = SpannableStringBuilder()
val boldSpan = StyleSpan(Typeface.BOLD)
builder.append("First Part Not Bold ")
.append("BOLD ", boldSpan, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)
.append("rest not bold")

Use HTML code in TextView using the Html class:
Spanned styledText = Html.fromHtml("First Part Not Bold <b>BOLD</b> rest not bold");
textView.setText(styledText);

This code should set to bold everything that comes inside the html bold tag. And it also deletes the tag so only the content inside is displayed.
SpannableStringBuilder sb = new SpannableStringBuilder("this is <b>bold</b> and this is <b>bold too</b> and this is <b>bold too, again</b>.");
Pattern p = Pattern.compile("<b>.*?</b>", Pattern.CASE_INSENSITIVE);
boolean stop = false;
while (!stop)
{
Matcher m = p.matcher(sb.toString());
if (m.find()) {
sb.setSpan(new StyleSpan(android.graphics.Typeface.BOLD), m.start(), m.end(), Spannable.SPAN_INCLUSIVE_INCLUSIVE);
sb.delete(m.end()-4, m.end());
sb.delete(m.start(), m.start() + 3);
}
else
stop = true;
}
This code can also be adapted for other html style tags, such as Superscript (sup tag), etc.
SpannableStringBuilder sb = new SpannableStringBuilder("text has <sup>superscript</sup> tag");
Pattern p = Pattern.compile("<sup>.*?</sup>", Pattern.CASE_INSENSITIVE);
boolean stop = false;
while (!stop)
{
Matcher m = p.matcher(sb.toString());
if (m.find()) {
sb.setSpan(new SuperscriptSpan(), m.start(), m.end(), Spannable.SPAN_INCLUSIVE_INCLUSIVE);
sb.delete(m.end()-6, m.end());
sb.delete(m.start(), m.start() + 5);
}
else
stop = true;
}
To set the color, just use the ForegroundColorSpan with setSpan.
sb.setSpan(new ForegroundColorSpan(Color.rgb(255, 0, 0)), m.start(), m.end(), Spannable.SPAN_INCLUSIVE_INCLUSIVE);
Hope it helps.

We can also use SpannableStringBuilder with TextAppearanceSpan to accomplish that. Follow the below steps to implement like that.
Create a style in styles.xml.
<style name="BoldStyle">
<!-- Can add other styling attributes -->
<item name="android:textStyle">bold</item>
......
</style>
Use the below code.
SpannableStringBuilder builder = new SpannableStringBuilder("First Part Not Bold BOLD rest not bold");
builder.setSpan(new TextAppearanceSpan(this, R.style.BoldStyle), 20, 24, 0);
((TextView)findViewById(R.id.tv7)).setText(builder);
That's it. Hope it'll help someone.

you can bold and resize a part of your string in kotlin
val s = SpannableStringBuilder()
.append("First Part Not Bold And No Resize ")
.bold { scale(1.5f, { append("Second Part By Bold And Resize " )}) }
.append("Third Part Not Bold And No Resize")
yourTextview.text = s

So I know this has been solved, and even as requested with SpannableStringBuilder but in the event you wanted to build a string more dynamically I figured I would put this up.
// Stuff needed
TextView DataTextView = (TextView)rootView.findViewById(R.id.DataView);
String Fields[] = {...database column names as strings... "x","y"};
String DataString = new String();
int start,stop; // Start and Stop of formatting
// Final Result
SpannableStringBuilder coloredString = new SpannableStringBuilder();
SpannableString temp; // Small segment of colored string
for (int i =0; i < Fields.length; i++)
{
if (database_result.containsKey(Fields[i])) // Be sure a field exists in the ContentValues
{
DataString = Fields[i]+": ";
start = DataString.length();
DataString = DataString+ +database_result.getAsInteger(Fields[i])+" ";
stop= DataString.length();
temp = new SpannableString(DataString);
temp.setSpan(new ForegroundColorSpan(Color.WHITE),start, stop, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
coloredString.append(temp);
}
}
DataTextView.setText(coloredString);
database_result is a ContentValues type that I constructed from the returned Cursor type of the SQL query. The only problem I had with this was at first it was only ColorSpaning the first segment. It seams that you need to declare a new ForegroundColorSpan every time you want to use one (or any other kind of span) in a loop.

Why would you use SpannableStringBuilder when you can use SpannableBuilder?? (https://gist.github.com/qtyq/90f9b4894069a8b3676c)
SpannableString ss = SpannableBuilder.init("First Part Not Bold BOLD rest not bold")
.makeBold("BOLD")
.create()

For Xamarin.Android:
SpannableStringBuilder TextoFormateado = new SpannableStringBuilder();
TextoFormateado.Append("Not Bold");
int start = TextoFormateado.Length();
TextoFormateado.Append("Bold and Red");
TextoFormateado.SetSpan(new ForegroundColorSpan(new Color(255, 0, 0, 149)),
start, TextoFormateado.Length(), SpanTypes.ExclusiveExclusive);
TextoFormateado.SetSpan(new StyleSpan(TypefaceStyle.Bold),
start, TextoFormateado.Length(), SpanTypes.ExclusiveExclusive);
TextoFormateado.Append("Not bold");
TxtFinalText.TextFormatted = TextoFormateado;

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 .

How to get a red asterisk in a <string> entry

How do you get a red asterisk in a entry so that you can display it at the end of the text to indicate its a required field, like: Enter your name * (asterisk will be red). Or, for that matter, anywhere within the text.

You can't do that through xml string resources. This can only be done via code. For this you need to use SpannableStringBuilder and ForegroundColorSpan.
Here is small example:
TextView text = (TextView)findViewById(R.id.text);
String simple = "Enter your name ";
String colored = "*";
SpannableStringBuilder builder = new SpannableStringBuilder();
builder.append(simple);
int start = builder.length();
builder.append(colored);
int end = builder.length();
builder.setSpan(new ForegroundColorSpan(Color.RED), start, end,
Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
text.setText(builder);

Refer to this for examples on how to style portions of a textview. Here's how you could do it for a red asterisk.
EditText editTxt = new EditText(this);
editTxt.setText("Testing asterisk *");
Spannable str = editTxt.getTxt();
int loc = editTxt.getTxt().toString().indexOf("*");
str.setSpan(new ForegroundColorSpan(Color.RED), loc, 1, Spannable.SPAN_INCLUSIVE_EXCLUSIVE);

Alternative for showing asterisk in android Textview
txtvw2.setText(Html.fromHtml("<sup>*</sup>"+"enter you name"));

Initialize variable in strings.xml <string name="date_of_incident">Date of Incident <p><font color="red">*</font></p></string>

Write into strings.xml file
<string name="KeyWord">KeyWord <font color='red'>*</font></string>
this helped me solve this problem.