ImageSpan 不显示或者变小

设置ImageSpan后不显示或者图片变小的问题~~

            SpannableString spanString = new SpannableString(content);
//          Drawable drawable = context.getResources().getDrawable(id);
//          drawable.setBounds(0, 0, 52, 32);// 设置 bounds显示图片
            Bitmap drawable = BitmapFactory.decodeResource(context.getResources(),id);
//          drawable.setDensity(160);  设置默认缩放比，否则会取手机的density
            CenterImageSpan imageSpan = new CenterImageSpan(context,drawable, -1000); // 建议的构造方法
            spanString.setSpan(imageSpan, start, end, Spannable.SPAN_INCLUSIVE_EXCLUSIVE);

图文混排居中对齐 CenterImageSpan
默认对齐方式： ImageSpan.ALIGN_BOTTOM 和 ImageSpan.ALIGN_BASELINE

public class CenterImageSpan extends ImageSpan {

    public CenterImageSpan(Context context, Bitmap b, int verticalAlignment) {
        super(context, b, verticalAlignment);
    }

    @Override
    public void draw(Canvas canvas, CharSequence text,int start, int end, float x,int top, int y, int bottom, Paint paint) {
        Drawable b = getDrawable();
        canvas.save();


        int transY = bottom - b.getBounds().bottom;

        if (mVerticalAlignment == ALIGN_BOTTOM) {

        }if (mVerticalAlignment == ALIGN_BASELINE) {
            transY -= paint.getFontMetricsInt().descent;
        }else {
            Paint.FontMetricsInt fm = paint.getFontMetricsInt();
            transY = (y + fm.descent + y + fm.ascent) / 2 - b.getBounds().bottom / 2;
        }

        canvas.translate(x, transY);
        b.draw(canvas);
        canvas.restore();
    }
}