前言

我们在开发金融类应用中经常遇到某某大，某某小的数字显示，还有中间有下划线数字，这些其实可以归纳统称为富文本文字，在Android解决中就有Spannable类可供解决，但是其富文本支持标签有限，查看TextView源码可知他会对传进的对象判断是否为Spannable再做对应处理，无法识别的会移除，虽然是这样，但是不影响今天所做的第一个实验，金融类大小数字

• SpannableString

图片.png

public static SpannableString spannableString(String str){
        SpannableString spannableString = new SpannableString(str);
        RelativeSizeSpan sizeSpan01 = new RelativeSizeSpan(1.3f);
        if(str.length()==1){
            //只有百分号
            SpannableString temp = new SpannableString("");
            temp.setSpan(sizeSpan01,0,str.length(), Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
            return temp;
        }else if(str.length()<=2){
            //只有1位数字
            spannableString.setSpan(sizeSpan01, 0, str.length()-1, Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
        }else {
            //超过1为数字
            if (str.contains(".")) {
                //有小数点
                int index = str.lastIndexOf(".");
                spannableString.setSpan(sizeSpan01, 0, index, Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
            } else {
                //无小数点
                spannableString.setSpan(sizeSpan01, 0, str.length()-1, Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
            }
        }
        return spannableString;
    }

• Html.from()方法显现html中的 图片

相信有很多网友跟我一样，在百度中看到有人介绍图片加载到数组中，但是写法上遇到了困难，停在那里，这里有找到的一个很好的富文本显示，与我一样稍作修改肯定就能满足你们的需求。
这里其实也是实现ImageGetter 接口加载的图片

@SuppressLint("AppCompatCustomView")
public class RichText extends TextView {
    private Drawable placeHolder, errorImage;//占位图，错误图
    private OnImageClickListener onImageClickListener;//图片点击回调
    private HashSet<Target> targets;
    private int d_w = 200;
    private int d_h = 200;
    public RichText(Context context) {
        this(context, null);
        init(context);
    }
    public RichText(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
        init(context);
    }
    public RichText(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context);
    }

    private void init(Context context){
        targets = new HashSet<>();
        d_w=50;
        d_h=50;
        placeHolder = context.getResources().getDrawable(R.drawable.ic_img_loading_place_holder);
        if (placeHolder == null) {
            placeHolder = new ColorDrawable(Color.GRAY);
        }
        placeHolder.setBounds(0, 0, d_w, d_h);
        errorImage = context.getResources().getDrawable(R.drawable.ic_img_load_error);
        if (errorImage == null) {
            errorImage = new ColorDrawable(Color.GRAY);
        }
        errorImage.setBounds(0, 0, d_w, d_h);
    }
    /**
     * 设置富文本
     * @param text 富文本
     */
    public void setRichText(String text) {
        targets.clear();
        Spanned spanned = Html.fromHtml(text, asyncImageGetter, null);
        SpannableStringBuilder spannableStringBuilder;
        if (spanned instanceof SpannableStringBuilder) {
            spannableStringBuilder = (SpannableStringBuilder) spanned;
        } else {
            spannableStringBuilder = new SpannableStringBuilder(spanned);
        }

        ImageSpan[] imageSpans = spannableStringBuilder.getSpans(0, spannableStringBuilder.length(), ImageSpan.class);
        final List<String> imageUrls = new ArrayList<>();

        for (int i = 0, size = imageSpans.length; i < size; i++) {
            ImageSpan imageSpan = imageSpans[i];
            String imageUrl = imageSpan.getSource();
            int start = spannableStringBuilder.getSpanStart(imageSpan);
            int end = spannableStringBuilder.getSpanEnd(imageSpan);
            imageUrls.add(imageUrl);

            final int finalI = i;
            ClickableSpan clickableSpan = new ClickableSpan() {
                @Override
                public void onClick(View widget) {
                    if (onImageClickListener != null) {
                        onImageClickListener.imageClicked(imageUrls, finalI);
                    }
                }
            };
            ClickableSpan[] clickableSpans = spannableStringBuilder.getSpans(start, end, ClickableSpan.class);
            if (clickableSpans != null && clickableSpans.length != 0) {
                for (ClickableSpan cs : clickableSpans) {
                    spannableStringBuilder.removeSpan(cs);
                }
            }
            spannableStringBuilder.setSpan(clickableSpan, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
        }
        super.setText(spanned);
        setMovementMethod(LinkMovementMethod.getInstance());
    }

    private void addTarget(Target target) {
        targets.add(target);
    }

    /**
     * 异步加载图片（依赖于Picasso）
     */
    private Html.ImageGetter asyncImageGetter = new Html.ImageGetter() {
        @Override
        public Drawable getDrawable(String url) {
            final URLDrawable urlDrawable = new URLDrawable();
            Target target = new Target() {
                @Override
                public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
                    Drawable drawable = new BitmapDrawable(getContext().getResources(), bitmap);
                    drawable.setBounds(0, 0, bitmap.getWidth(), bitmap.getHeight());
                    urlDrawable.setBounds(0, 0, bitmap.getWidth(), bitmap.getHeight());
                    urlDrawable.setDrawable(drawable);
                    RichText.this.setText(getText());
                    Log.i("mtg","图片加载成功");
                }

                @Override
                public void onBitmapFailed(Exception e, Drawable errorDrawable) {
                    urlDrawable.setBounds(errorDrawable.getBounds());
                    urlDrawable.setDrawable(errorDrawable);
                    Log.i("mtg","图片加载失败");
                }

                @Override
                public void onPrepareLoad(Drawable placeHolderDrawable) {
                    urlDrawable.setBounds(placeHolderDrawable.getBounds());
                    urlDrawable.setDrawable(placeHolderDrawable);
                    Log.i("mtg","图片加载开始加载");
                }
            };
            addTarget(target);
            String uri = REQUEST_LIST + url;
//            uri="https://static.firefoxchina.cn/img/201807/5_5b5920a27d11d0.jpg";
            Log.i("mgg","picasso加载图片："+uri);
            Picasso.get()
                    .load(uri)
                    .placeholder(placeHolder)
                    .error(errorImage)
                    .into(target);
            return urlDrawable;
        }
    };

    private static final class URLDrawable extends BitmapDrawable {
        private Drawable drawable;

        @SuppressWarnings("deprecation")
        public URLDrawable() {
        }

        @Override
        public void draw(Canvas canvas) {
            if (drawable != null)
                drawable.draw(canvas);
        }

        public void setDrawable(Drawable drawable) {
            this.drawable = drawable;
        }
    }

    public void setPlaceHolder(Drawable placeHolder) {
        this.placeHolder = placeHolder;
        this.placeHolder.setBounds(0, 0, d_w, d_h);
    }

    public void setErrorImage(Drawable errorImage) {
        this.errorImage = errorImage;
        this.errorImage.setBounds(0, 0, d_w, d_h);
    }

    public void setOnImageClickListener(OnImageClickListener onImageClickListener) {
        this.onImageClickListener = onImageClickListener;
    }

    public interface OnImageClickListener {
        /**
         * 图片被点击后的回调方法
         *
         * @param imageUrls 本篇富文本内容里的全部图片
         * @param position  点击处图片在imageUrls中的位置
         */
        void imageClicked(List<String> imageUrls, int position);
    }

ic_img_load_error.png

ic_img_loading_place_holder.png