Subscript and Superscript a String in Android

Question

How can you print a string with a subscript or superscript? Can you do this without an external library? I want this to display in a TextView in Android.

Answer 1

The HTML.fromHTML(String) was deprecated as of API 24. They say to use this one instead, which supports flags as a parameter. So to go off of the accepted answer:

TextView textView = ((TextView)findViewById(R.id.text));
textView.setText(Html.fromHtml("X<sup>2</sup>", Html.FROM_HTML_MODE_LEGACY));

And if you want code that considers pre-24 API's as well:

TextView textView = ((TextView)findViewById(R.id.text));
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
  textView.setText(Html.fromHtml("X<sup>2</sup>", Html.FROM_HTML_MODE_LEGACY));
} else {
    textView.setText(Html.fromHtml("X<sup>2</sup>"));    
}

This answer was derived from: https://stackoverflow.com/a/37905107/4998704

The flags and other documentation can be found here: https://developer.android.com/reference/android/text/Html.html

Answer 2

In the strings.xml files, you can just use the HTML <sup>3</sup> tag. Work perfectly for me

EXAMPLE

<string name="turnoverRate">Turnover rate m<sup>3</sup>/m<sup>2</sup>/hour:</string>

Answer 3

They are called Unicode characters, and Android TextView supports them. Copy the super/sub-script you want from this Wiki: https://en.wikipedia.org/wiki/List_of_Unicode_characters#Superscripts_and_Subscripts

Answer 4

The Accepted answer is deprecated now. So please go through this piece of code. I got this from some website. I forgot the name but anyway thanks for this good piece of working code.

     SpannableString styledString
            = new SpannableString("Large\n\n"     // index 0 - 5
            + "Bold\n\n"          // index 7 - 11
            + "Underlined\n\n"    // index 13 - 23
            + "Italic\n\n"        // index 25 - 31
            + "Strikethrough\n\n" // index 33 - 46
            + "Colored\n\n"       // index 48 - 55
            + "Highlighted\n\n"   // index 57 - 68
            + "K Superscript\n\n" // "Superscript" index 72 - 83 
            + "K Subscript\n\n"   // "Subscript" index 87 - 96
            + "Url\n\n"           //  index 98 - 101
            + "Clickable\n\n");   // index 103 - 112

    // make the text twice as large
    styledString.setSpan(new RelativeSizeSpan(2f), 0, 5, 0);

    // make text bold
    styledString.setSpan(new StyleSpan(Typeface.BOLD), 7, 11, 0);

    // underline text
    styledString.setSpan(new UnderlineSpan(), 13, 23, 0);

    // make text italic
    styledString.setSpan(new StyleSpan(Typeface.ITALIC), 25, 31, 0);

    styledString.setSpan(new StrikethroughSpan(), 33, 46, 0);

    // change text color
    styledString.setSpan(new ForegroundColorSpan(Color.GREEN), 48, 55, 0);

    // highlight text
    styledString.setSpan(new BackgroundColorSpan(Color.CYAN), 57, 68, 0);

    // superscript
    styledString.setSpan(new SuperscriptSpan(), 72, 83, 0);
    // make the superscript text smaller
    styledString.setSpan(new RelativeSizeSpan(0.5f), 72, 83, 0);

    // subscript
    styledString.setSpan(new SubscriptSpan(), 87, 96, 0);
    // make the subscript text smaller
    styledString.setSpan(new RelativeSizeSpan(0.5f), 87, 96, 0);

    // url
    styledString.setSpan(new URLSpan("http://www.google.com"), 98, 101, 0);

    // clickable text
    ClickableSpan clickableSpan = new ClickableSpan() {

        @Override
        public void onClick(View widget) {
            // We display a Toast. You could do anything you want here.
            Toast.makeText(MainActivity.this, "Clicked", Toast.LENGTH_SHORT).show();

        }
    };

    styledString.setSpan(clickableSpan, 103, 112, 0);


    // Give the styled string to a TextView
    spantext = (TextView) findViewById(R.id.spantext);


    // this step is mandated for the url and clickable styles.
    spantext.setMovementMethod(LinkMovementMethod.getInstance());

    // make it neat
    spantext.setGravity(Gravity.CENTER);
    spantext.setBackgroundColor(Color.WHITE);

    spantext.setText(styledString);

Note : Always put android:textAllCaps="false" of your spantext.

Answer 5

To all people asking, if you want to make it smaller besides of making super or subscript, you just need to add tag as well. EX:

"X <sup><small> 2 </small></sup>"

Answer 6

Example:

equation = (TextView) findViewById(R.id.textView1);
SpannableStringBuilder cs = new SpannableStringBuilder("X3 + X2");
cs.setSpan(new SuperscriptSpan(), 1, 2, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
cs.setSpan(new RelativeSizeSpan(0.75f), 1, 2, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
cs.setSpan(new SuperscriptSpan(), 6, 7, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
cs.setSpan(new RelativeSizeSpan(0.75f), 6, 7, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
equation.setText(cs);