HarmonyOS鸿蒙Next中如何将kotlin自定义高亮文本组件转换成ArkTS

HarmonyOS鸿蒙Next中如何将kotlin自定义高亮文本组件转换成ArkTS

class HighlightTextView @JvmOverloads constructor(
    context: Context,
    attrs: AttributeSet? = null,
    defStyleAttr: Int = 0
) : AppCompatTextView(context, attrs, defStyleAttr) {

    private val paint = Paint(Paint.ANTI_ALIAS_FLAG)

    companion object {
        const val HIGHLIGHT_RECT = 0 // 矩形高亮
        const val HIGHLIGHT_ROUND = 1 // 圆形高亮
    }

    init {
        paint.style = Paint.Style.FILL
    }

    private data class HighlightInfo(
      val highlightText: String,
      val highlightColor: Int,
      val highlightStyle: Int,
      var matchAll: Boolean,
    )
    private val highlights = mutableListOf<HighlightInfo>()

    fun addHighlight(text: String, color: Int, style: Int, matchAll: Boolean) {
      highlights.add(HighlightInfo(text, color, style, matchAll))
      invalidate()
    }

    fun clearHighlights() {
      highlights.clear()
      invalidate()
    }


  override fun onDraw(canvas: Canvas) {
    val content = text.toString()
    // 获取文字的Paint参数
//    val textPaint = getPaint()
    // 获取文字的度量信息
//    val fontMetrics = textPaint.fontMetrics

    // 遍历所有高亮区域
    for (highlight in highlights) {
      var searchStart = 0
      while (searchStart < content.length) {
        // 直接查找完整匹配，包含换行符
        val matchStart = content.indexOf(highlight.highlightText, searchStart)
        if (matchStart == -1) break

        val matchEnd = matchStart + highlight.highlightText.length

        // 找到匹配，绘制高亮
        val highlightViewLayout = layout
        if (highlightViewLayout != null) {
          // 获取起始位置所在的行
          val startLine = highlightViewLayout.getLineForOffset(matchStart)
          // 获取结束位置所在的行
          val endLine = highlightViewLayout.getLineForOffset(matchEnd - 1)

          // 遍历每一行进行绘制
          for (line in startLine..endLine) {
            // 计算当前行需要高亮的起始和结束位置
            val lineStart = highlightViewLayout.getLineStart(line)
            val lineEnd = highlightViewLayout.getLineEnd(line)

            // 计算当前行实际需要高亮的范围
            val highlightLineStart = maxOf(matchStart, lineStart)
            // 调整行尾位置，如果是换行符则不包含它
            val adjustedLineEnd = if (content.getOrNull(lineEnd - 1) == '\n') {
              lineEnd - 1
            } else {
              lineEnd
            }
            val highlightLineEnd = minOf(matchEnd, adjustedLineEnd)

            // 只有当当前行包含需要高亮的内容时才绘制
            if (highlightLineStart <= highlightLineEnd) {
              // 获取当前行文字的水平位置
              val startX = highlightViewLayout.getPrimaryHorizontal(highlightLineStart)
              // 使用当前行的实际结束位置
              val endX = if (highlightLineEnd == lineEnd) {
                // 如果是行尾，使用行宽
                highlightViewLayout.getLineWidth(line).toFloat()
              } else {
                highlightViewLayout.getPrimaryHorizontal(highlightLineEnd)
              }
              val lineTop = highlightViewLayout.getLineTop(line)
              val lineBottom = highlightViewLayout.getLineBottom(line)

              paint.color = highlight.highlightColor

              // 添加适当的padding
              // 计算文字的实际高度
              val lineHeight = lineBottom - lineTop
//              MyLogger.d("lxp", "startX: $startX endX: $endX lineTop: $lineTop lineBottom: $lineBottom")
//              MyLogger.d("lxp", "fontMetrics: ascent: ${fontMetrics.ascent} descent:${fontMetrics.descent} top: ${fontMetrics.top} bottom: ${fontMetrics.bottom}")

              when (highlight.highlightStyle) {
                HIGHLIGHT_RECT -> {
                  val verticalPadding = lineHeight * 0.45f  // 可以调整这个值来控制padding
                  canvas.drawRect(
                    startX + paddingLeft,
                    lineTop.toFloat() + verticalPadding,
                    endX + paddingLeft,
                    lineBottom.toFloat(),
                    paint
                  )
                }

                HIGHLIGHT_ROUND -> {
                  val horizontalPadding = paddingLeft
                  // 遍历每个字符，分别绘制圆形背景
                  for (i in highlightLineStart until highlightLineEnd) {
                    val charStart = highlightViewLayout.getPrimaryHorizontal(i)
                    val charEnd = highlightViewLayout.getPrimaryHorizontal(i + 1)
                    val charWidth = charEnd - charStart
                    val centerX = (charStart + charEnd) / 2
                    val centerY = (lineTop + lineBottom) / 2f

                    val radius = (charWidth * 1.1f) / 2f

                    canvas.drawCircle(
                      centerX + horizontalPadding,
                      centerY,
                      radius,
                      paint
                    )
                  }
                }
              }
            }
          }
          if (highlight.matchAll.not()) {
            //只匹配第一个
           break
          }
          searchStart = matchEnd
        } else {
          break
        }
      }

    }
    super.onDraw(canvas)
  }
}