Android TextView superscript

问题:

So I'm trying to add superscipt/subscript to a TextView, basically trying to make a fraction be displayed as ¹/₂. Not sure where I'm going wrong, and I'm new with Android, so any help is appreciated. Thanks!

SpannableStringBuilder numSpan = new SpannableStringBuilder(String.valueOf(num));
SpannableStringBuilder denSpan = new SpannableStringBuilder(String.valueOf(den));

numSpan.setSpan(new SuperscriptSpan(), 0, numSpan.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
denSpan.setSpan(new SubscriptSpan(), 0, denSpan.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

outputText.setText(numSpan + "/" + denSpan, TextView.BufferType.SPANNABLE););

回答1:

Try Html.fromHtml instead. Simple and precise:

outputText.setText(Html.fromHtml("<sup>" + num + "</sup>/<sub>" + den + "</sub>"));

Note: You may need to give some height to the textview else the output will be clipped.

Alternatively, you could try this, where the number size is smaller:

outputText.setText(Html.fromHtml("<sup><small>" + num + "</small></sup>/<sub><small>" + den + "</small></sub>"));

回答2:

You can use RelativeSizeSpan

numSpan.setSpan(new SuperscriptSpan(), 0, numSpan.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
numSpan.setSpan(new RelativeSizeSpan(0.5f), 0, numSpan.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

or AbsoluteSizeSpan

numSpan.setSpan(new SuperscriptSpan(), 0, numSpan.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
numSpan.setSpan(new AbsoluteSizeSpan(28), 0, numSpan.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);