Drawable与TextView第一行对齐，后拼接不同颜色文本

实现左边drawable只与第一行对齐，置顶拼接在文本后方，可随文本输入向后移动

第一行对齐

1.导入三方框架

implementation 'com.github.ithedan:TextViewDrawable:v1.0'

2.XML

3.圆形Drawable
bg_circle_mini_gray.xml

拼接实现

package com.wttech.tiefa.view;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.support.annotation.NonNull;
import android.text.TextPaint;
import android.text.TextUtils;
import android.text.style.ReplacementSpan;
import android.util.TypedValue;

public class RoundBackgroundColorSpan extends ReplacementSpan {
        private Context mContext;
        private int mBgColorResId; //Icon背景颜色
        private String mText;  //Icon内文字
        private float mBgHeight;  //Icon背景高度
        private float mBgWidth;  //Icon背景宽度
        private float mRadius;  //Icon圆角半径
        private float mRightMargin; //右边距
        private float mTextSize; //文字大小
        private int mTextColorResId; //文字颜色

        private Paint mBgPaint; //icon背景画笔
        private Paint mTextPaint; //icon文字画笔

        public RoundBackgroundColorSpan(Context context, int bgColorResId,int textColor,int textSize, String text) {
            if (TextUtils.isEmpty(text)) {
                return;
            }
            //初始化默认数值
            initDefaultValue(context, bgColorResId, text,textColor,textSize);
            //计算背景的宽度
            this.mBgWidth = caculateBgWidth(text);
            //初始化画笔
            initPaint();
        }

        /**
         * 初始化画笔
         */
        private void initPaint() {
            //初始化背景画笔
            mBgPaint = new Paint();
            mBgPaint.setColor(mContext.getResources().getColor(mBgColorResId));
            mBgPaint.setStyle(Paint.Style.FILL);
            mBgPaint.setAntiAlias(true);

            //初始化文字画笔
            mTextPaint = new TextPaint();
            mTextPaint.setColor(mContext.getResources().getColor(mTextColorResId));
            mTextPaint.setTextSize(mTextSize);
            mTextPaint.setAntiAlias(true);
            mTextPaint.setTextAlign(Paint.Align.CENTER);
        }

        /**
         * 初始化默认数值
         *
         * @param context
         */
        private void initDefaultValue(Context context, int bgColorResId, String text,int textColor,int textSize) {
            this.mContext = context.getApplicationContext();
            this.mBgColorResId = bgColorResId;
            this.mText = text;
            this.mBgHeight = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 17f, mContext.getResources().getDisplayMetrics());
            this.mRightMargin = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 2, mContext.getResources().getDisplayMetrics());
            this.mRadius = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 2, mContext.getResources().getDisplayMetrics());
            this.mTextSize = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, textSize, mContext.getResources().getDisplayMetrics());
            this.mTextColorResId = textColor;
        }

        /**
         * 计算icon背景宽度
         *
         * @param text icon内文字
         */
        private float caculateBgWidth(String text) {
            if (text.length() > 1) {
                //多字，宽度=文字宽度+padding
                Rect textRect = new Rect();
                Paint paint = new Paint();
                paint.setTextSize(mTextSize);
                paint.getTextBounds(text, 0, text.length(), textRect);
                float padding = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 4, mContext.getResources().getDisplayMetrics());
                return textRect.width() + padding * 2;
            } else {
                //单字，宽高一致为正方形
                return mBgHeight;
            }
        }

        /**
         * 设置右边距
         *
         * @param rightMarginDpValue
         */
        public void setRightMarginDpValue(int rightMarginDpValue) {
            this.mRightMargin = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, rightMarginDpValue, mContext.getResources().getDisplayMetrics());
        }

        /**
         * 设置宽度，宽度=背景宽度+右边距
         */
        @Override
        public int getSize(@NonNull Paint paint, CharSequence text, int start, int end, Paint.FontMetricsInt fm) {
            return (int) (mBgWidth + mRightMargin);
        }

        /**
         * draw
         * @param text 完整文本
         * @param start setSpan里设置的start
         * @param end setSpan里设置的start
         * @param x
         * @param top 当前span所在行的上方y
         * @param y y其实就是metric里baseline的位置
         * @param bottom 当前span所在行的下方y(包含了行间距)，会和下一行的top重合
         * @param paint 使用此span的画笔
         */
        @Override
        public void draw(@NonNull Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom, Paint paint) {
            //画背景
            Paint bgPaint = new Paint();
            bgPaint.setColor(mContext.getResources().getColor(mBgColorResId));
            bgPaint.setStyle(Paint.Style.FILL);
            bgPaint.setAntiAlias(true);
            Paint.FontMetrics metrics = paint.getFontMetrics();

            float textHeight = metrics.descent - metrics.ascent;
            //算出背景开始画的y坐标
            float bgStartY = y + (textHeight - mBgHeight) / 2 + metrics.ascent;

            //画背景
            RectF bgRect = new RectF(x, bgStartY, x + mBgWidth, bgStartY + mBgHeight);
            canvas.drawRoundRect(bgRect, mRadius, mRadius, bgPaint);

            //把字画在背景中间
            TextPaint textPaint = new TextPaint();
            textPaint.setColor(mContext.getResources().getColor(mTextColorResId));
            textPaint.setTextSize(mTextSize);
            textPaint.setAntiAlias(true);
            textPaint.setTextAlign(Paint.Align.CENTER);  //这个只针对x有效
            Paint.FontMetrics fontMetrics = textPaint.getFontMetrics();
            float textRectHeight = fontMetrics.bottom - fontMetrics.top;
            canvas.drawText(mText, x + mBgWidth / 2, bgStartY + (mBgHeight - textRectHeight) / 2 - fontMetrics.top, textPaint);
        }
}

2.调用方法

        com.hedan.textdrawablelibrary.TextViewDrawable textView = findViewById(R.id.tv_detail);
        StringBuilder stringBuilder = new StringBuilder();
        String content = "测试测试测试测试测试测试测试测试测试测试测试测试测试测试测试测试。";
        String endText = "置顶";
        stringBuilder.append(content);
        stringBuilder.append(endText);
        RoundBackgroundColorSpan endSpan = new RoundBackgroundColorSpan(context, R.color.zero_bg_unfinish_green, R.color.zero_text_unfinish_green, 10, endText);
        SpannableString span = new SpannableString(stringBuilder.toString());
        span.setSpan(endSpan, span.length() - endText.length(), span.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
        textView.setText(span);