Android String处理(SpannableString,HTML)

SpannableString：

SpannableString在strings.xml对应关系（StringBlock.java）

• Spanned.SPAN_EXCLUSIVE_EXCLUSIVE — 不包含两端start和end所在的端点
• Spanned.SPAN_EXCLUSIVE_INCLUSIVE — 不包含start，但包含end
• Spanned.SPAN_INCLUSIVE_EXCLUSIVE — 包含start，但不包含end
• Spanned.SPAN_INCLUSIVE_INCLUSIVE— 包含start和end所在的端点

   public void testSetSpan() {
        String text = "hello, world";
        SpannableString spannable = new SpannableString(text);

        spannable.setSpan(null, 1, 4, SpannableString.SPAN_POINT_POINT);
        assertEquals(1, spannable.getSpanStart(null));
        assertEquals(4, spannable.getSpanEnd(null));
        assertEquals(SpannableString.SPAN_POINT_POINT, spannable.getSpanFlags(null));

        UnderlineSpan underlineSpan = new UnderlineSpan();
        spannable.setSpan(underlineSpan, 0, 2, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
        assertEquals(0, spannable.getSpanStart(underlineSpan));
        assertEquals(2, spannable.getSpanEnd(underlineSpan));
        assertEquals(SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE,
                spannable.getSpanFlags(underlineSpan));

        try {
            spannable.setSpan(null, 4, 1, SpannableString.SPAN_POINT_POINT);
            fail("should throw IndexOutOfBoundsException here");
        } catch (IndexOutOfBoundsException e) {
        }

        try {
            spannable.setSpan(underlineSpan, -1, text.length() + 1,
                    SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
            fail("should throw IndexOutOfBoundsException here");
        } catch (IndexOutOfBoundsException e) {
        }
    }

   public void testRemoveSpan() {
        SpannableString spannable = new SpannableString("hello, world");

        spannable.removeSpan(null);

        UnderlineSpan underlineSpan = new UnderlineSpan();
        spannable.setSpan(underlineSpan, 0, 2, 2);
        assertEquals(0, spannable.getSpanStart(underlineSpan));
        assertEquals(2, spannable.getSpanEnd(underlineSpan));
        assertEquals(2, spannable.getSpanFlags(underlineSpan));

        spannable.removeSpan(underlineSpan);
        assertEquals(-1, spannable.getSpanStart(underlineSpan));
        assertEquals(-1, spannable.getSpanEnd(underlineSpan));
        assertEquals(0, spannable.getSpanFlags(underlineSpan));

        // try to test removeSpan when there are no spans
        spannable.removeSpan(underlineSpan);
        assertEquals(-1, spannable.getSpanStart(underlineSpan));
        assertEquals(-1, spannable.getSpanEnd(underlineSpan));
        assertEquals(0, spannable.getSpanFlags(underlineSpan));
    }

HTML:

TextView textView = new TextView(context);
        textView.setText(Html.fromHtml("some html text"));