Android:使用 LeadingMarginSpan 在文本视图中显示项目符号列表?

Android: display bullet list in a textview using LeadingMarginSpan?

我想在文本视图中显示项目符号列表。我可以使用 bulletspan,但是子弹不是很吸引人,而且似乎没有自定义它的方法。我想为我的要点列表使用默认项目符号 (•)。有没有办法使用 LeadingMarginSpan 来获得我想要的效果?基本上,如果该行以项目符号开头,我希望它向左对齐,但是如果该行太长以至于它会中断,那么下一行的文本(中断的文本)应该缩进到与后面的文本相同的水平要点。

* for example
instead of this

* for example
  should look like this

我当前的代码:

String[] bulletpoint = {some array of strings};
CharSequence allText = "";

for (int i = 0; i < bulletpoint.length; i++) {
    String text = bulletpoint[i];
    SpannableString s = new SpannableString(text + "\n");
    s.setSpan(new LeadingMarginSpan(BulletSpan.STANDARD_GAP_WIDTH) {
        @Override
        public int getLeadingMargin(boolean first) {
            return 0;
        }
        @Override
        public void drawLeadingMargin(Canvas c, Paint p, int x, int dir, int top, int baseline, int bottom, CharSequence text, int start, int end, boolean first, Layout layout) {

        }
    }, 0, text.length(), 0);
    allText = TextUtils.concat(allText, s);
}
textview.settext(allText);

您可以使用 BulletSpanLeadingMarginSpan 实现,只需覆盖 drawLeadingMargin() 即可按照您想要的方式绘制项目符号。

参考 BulletSpan 的代码,了解他们如何绘制子弹并将其用作指南:

BulletSpan source code

用代码示例回答:

CharSequence allText = "";
for (String aBulletpoint : bulletpoint) {
    String text = aBulletpoint.trim() + ".";
    SpannableString spannableString = new SpannableString(text + "\n");
    spannableString.setSpan(new LeadingMarginSpan() {
        @Override
        public int getLeadingMargin(boolean first) {
            return getString(R.string.bulletpoint).length() * 50;
        }
        @Override
        public void drawLeadingMargin(Canvas c, Paint p, int x, int dir, int top, int baseline, int bottom, CharSequence text, int start, int end, boolean first, Layout layout) {
            if (first) {
                Paint.Style orgStyle = p.getStyle();
                p.setStyle(Paint.Style.FILL);
                c.drawText(getString(R.string.bulletpoint) + " ", 0, bottom - p.descent(), p);
                p.setStyle(orgStyle);
            }
         }
    }, 0, text.length(), 0);
    allText = TextUtils.concat(allText, spannableString);
}
someTextView.setText(allText);