Using span to insert tab in textview

问题

Is there a way to add a tab character to a piece of text using span in textview? From the developer documentation, I came across TabStopSpan (see here) and tried to use it in a TextView like so:

String source = "Hello World! Let's select some text!!";

        SpannableString s = new SpannableString(source);
        s.setSpan(new TabStopSpan() {
            @Override
            public int getTabStop() {
                return 100;
            }
        }, 5, 10, 0);
ed.setText(s, BufferType.SPANNABLE);

Where ed is a TextView. The above snippet does not do anything and the documentation is so less as to be pretty much useless. Is there any way to add a tab character to a TextView using spans?

回答1:

Just add "\t" for a tab, "\n" for a new line. For example:

String source = "Hello!\tLets select some text!";

回答2:

Yes. combination of "\t" and TabStopSpannable will do the trick. The snippet below adds a tab between firstString and secondString:

    SpannableStringBuilder span = new SpannableStringBuilder(firstString +"\t"+ secondString);
    span.setSpan(new TabStopSpan.Standard(600), 0, span.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE );
    }

    ((TextView) v).setText(span, TextView.BufferType.SPANNABLE);

Be careful to use a meaningful value in the TabStopSpan.Standard constructor, preferably based on screendimensions.

回答3:

use this.

public static SpannableStringBuilder getTabText(String text, float stop)
{
    int column = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, stop, SystemMaster.getResources().getDisplayMetrics());

    SpannableStringBuilder span = new SpannableStringBuilder(text);
    span.setSpan(new TabStopSpan.Standard(column), 0, span.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
    return span;
}

and then

Text text = "xx \t yy \n aa \t bb";
SpannableStringBuilder sp = TextHelper.getTabText(text, 100);
tv.setText(sp);

来源：https://stackoverflow.com/questions/19121125/using-span-to-insert-tab-in-textview

标签

android

textview

tabstop