Vue と Canvas: マルチレベルのグラフィック描画と操作を実装する方法

<template>
  <div>
    <canvas :id="canvasId"></canvas>
  </div>
</template>

<script>
export default {
  data() {
    return {
      canvasId: 'myCanvas' // 指定Canvas的id
    }
  },
  mounted() {
    this.initCanvas()
  },
  methods: {
    initCanvas() {
      const canvas = document.getElementById(this.canvasId)
      this.context = canvas.getContext('2d')
    }
  }
}
</script>

methods: {
  initCanvas() {
    const canvas = document.getElementById(this.canvasId)
    this.context = canvas.getContext('2d')

    // 绘制底层图形
    this.context.fillStyle = 'red'
    this.context.fillRect(0, 0, canvas.width, canvas.height)
  }
}

methods: {
  initCanvas() {
    const canvas = document.getElementById(this.canvasId)
    this.context = canvas.getContext('2d')

    // 绘制底层图形
    this.context.fillStyle = 'red'
    this.context.fillRect(0, 0, canvas.width, canvas.height)

    // 绑定事件监听器
    canvas.addEventListener('click', this.drawCircle)
  },
  drawCircle(event) {
    const canvas = document.getElementById(this.canvasId)
    const rect = canvas.getBoundingClientRect()

    const x = event.clientX - rect.left
    const y = event.clientY - rect.top

    // 绘制圆形
    this.context.beginPath()
    this.context.arc(x, y, 50, 0, 2 * Math.PI)
    this.context.fillStyle = 'blue'
    this.context.fill()
  }
}

<template>
  <div>
    <canvas :id="canvasId"></canvas>
    <button @click="clearCanvas">清空</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      canvasId: 'myCanvas' // 指定Canvas的id
    }
  },
  mounted() {
    this.initCanvas()
  },
  methods: {
    initCanvas() {
      const canvas = document.getElementById(this.canvasId)
      this.context = canvas.getContext('2d')

      // 绘制底层图形
      this.context.fillStyle = 'red'
      this.context.fillRect(0, 0, canvas.width, canvas.height)

      // 绑定事件监听器
      canvas.addEventListener('click', this.drawCircle)
    },
    drawCircle(event) {
      const canvas = document.getElementById(this.canvasId)
      const rect = canvas.getBoundingClientRect()

      const x = event.clientX - rect.left
      const y = event.clientY - rect.top

      // 绘制圆形
      this.context.beginPath()
      this.context.arc(x, y, 50, 0, 2 * Math.PI)
      this.context.fillStyle = 'blue'
      this.context.fill()
    },
    clearCanvas() {
      const canvas = document.getElementById(this.canvasId)
      this.context.clearRect(0, 0, canvas.width, canvas.height)
    }
  }
}
</script>