Android - 当部分删除时删除整个ImageSpan？

Question

我通过插入ImageSpan将图像添加到我的edittext中.我对跨度没有透彻的了解,但似乎我的ImageSpan需要包装一部分文本.所以我在EditText中添加了一些文本,并用ImageSpan包装它,看起来很好.但是,当我退格ImageSpan时,它只删除文本的一个字符,图像将保留,直到整个文本被删除.如何使用一个退格键删除它？

SpannableStringBuilder builder = new SpannableStringBuilder();
builder.append(content.getText());

String imgId = "[some useful text]"; 

int selStart = content.getSelectionStart();

builder.replace(content.getSelectionStart(), content.getSelectionEnd(), imgId);

builder.setSpan(imageSpan, selStart, selStart+imgId.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
content.setText(builder);

Answer 1

过了一段时间,我找到了解决方案.试试这段代码:

private TextWatcher watcher = new TextWatcher() {
    private int spanLength = -1;

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        if (start == 0) return;
        if (count > after) {
            ImageSpan[] spans = getEditableText().getSpans(start + count, start + count, ImageSpan.class);
            if (spans == null || spans.length == 0) return;
            for (int i = 0; i < spans.length; i++) {
                int end = getEditableText().getSpanEnd(spans[i]);
                if (end != start + count) continue;
                String text = spans[i].getSource();
                spanLength = text.length() - 1;
                getEditableText().removeSpan(spans[i]);
            }
        }
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        if (spanLength > -1) {
            int length = spanLength;
            spanLength = -1;
            getEditableText().replace(start - length, start, "");
        }
    }

    @Override
    public void afterTextChanged(Editable s) {
    }
};

但是您应该使用原始String创建ImageStan,如下所示:

ssb.setSpan(new ImageSpan(bmpDrawable, originalStr), x, x + originalStr.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);