String sampleText = "This is a test strike";
textView.setPaintFlags(tv.getPaintFlags()| Paint.STRIKE_THRU_TEXT_FLAG);
textView.setText(sampleText);

String sampleText = "This is a test strike";
SpannableStringBuilder spanBuilder = new SpannableStringBuilder(sampleText);
StrikethroughSpan strikethroughSpan = new StrikethroughSpan();
spanBuilder.setSpan(
        strikethroughSpan, // Span to add
        0, // Start
        4, // End of the span (exclusive)
        Spanned.SPAN_EXCLUSIVE_EXCLUSIVE // Text changes will not reflect in the strike changing
);
textView.setText(spanBuilder);