vue2.0如何实现一个一行四列的数据，已知总数和每列的数量，如何计算出每列所占每行总数的整数比，并且计算出来的比例要在最大值和最小值的范围之内

可以使用计算属性和watch来计算出每列所占每行总数的整数比，并且计算出来的比例要在最大值和最小值的范围之内。具体实现步骤如下：

1. 在data中定义总数、每列的数量、最大比例和最小比例的范围：

data() {
  return {
    total: 20,
    columnCount: 4,
    maxRatio: 50, // 最大比例
    minRatio: 10, // 最小比例
    maxTotal: 0, // 最大值
    minTotal: 0, // 最小值
  }
}

2. 在mounted钩子函数中计算最大值和最小值：

mounted() {
  this.updateMinMaxTotal();
}

methods: {
  updateMinMaxTotal() {
    const { total, columnCount, maxRatio, minRatio } = this;
    this.maxTotal = maxRatio * columnCount;
    this.minTotal = minRatio * columnCount;
    if (total > this.maxTotal) {
      this.total = this.maxTotal;
    } else if (total < this.minTotal) {
      this.total = this.minTotal;
    }
  }
}

3. 在计算属性中计算每列所占每行总数的整数比：

computed: {
  columnRatio() {
    const { total, columnCount, maxRatio, minRatio, maxTotal, minTotal } = this;
    const columnTotal = Math.floor(total / columnCount);
    const remainder = total % columnCount;
    const ratios = Array(columnCount).fill(columnTotal);
    for (let i = 0; i < remainder; i++) {
      ratios[i]++;
    }
    const totalRatio = ratios.reduce((prev, curr) => prev + curr, 0);
    if (totalRatio > maxTotal) {
      const ratio = maxTotal / totalRatio;
      return ratios.map(val => Math.floor(val * ratio));
    } else if (totalRatio < minTotal) {
      const ratio = minTotal / totalRatio;
      return ratios.map(val => Math.floor(val * ratio));
    } else {
      return ratios.map(val =>
        Math.max(Math.min(val, maxRatio), minRatio)
      );
    }
  }
}

4. 在watch中监测总数、最大比例和最小比例的变化，更新数据：

watch: {
  total(newVal) {
    if (newVal > this.maxTotal) {
      this.total = this.maxTotal;
      return;
    } else if (newVal < this.minTotal) {
      this.total = this.minTotal;
      return;
    }
    this.updateColumnRatio();
  },
  maxRatio(newVal) {
    if (newVal < this.minRatio) {
      this.maxRatio = this.minRatio;
      return;
    }
    this.updateMinMaxTotal();
    this.updateColumnRatio();
  },
  minRatio(newVal) {
    if (newVal > this.maxRatio) {
      this.minRatio = this.maxRatio;
      return;
    }
    this.updateMinMaxTotal();
    this.updateColumnRatio();
  }
},
methods: {
  updateColumnRatio() {
    const ratios = this.columnRatio;
    this.columnRatio = ratios.map(val =>
      Math.max(Math.min(val, this.maxRatio), this.minRatio)
    );
  }
}

5. 在模板中使用v-for循环渲染数据，并将每列所占每行总数的整数比作为样式flex-basis的值：

<template>
  <div class="container">
    <div v-for="(ratio, index) in columnRatio"
         :key="index"
         class="column"
         :style="{ flexBasis: ratio + '%' }">
      {{ ratio }}
    </div>
  </div>
</template>

完整代码示例如下：

<template>
  <div class="container">
    <div v-for="(ratio, index) in columnRatio"
         :key="index"
         class="column"
         :style="{ flexBasis: ratio + '%' }">
      {{ ratio }}
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      total: 20,
      columnCount: 4,
      maxRatio: 50,
      minRatio: 10,
      maxTotal: 0,
      minTotal: 0,
    }
  },
  mounted() {
    this.updateMinMaxTotal();
  },
  computed: {
    columnRatio() {
      const { total, columnCount, maxRatio, minRatio, maxTotal, minTotal } = this;
      const columnTotal = Math.floor(total / columnCount);
      const remainder = total % columnCount;
      const ratios = Array(columnCount).fill(columnTotal);
      for (let i = 0; i < remainder; i++) {
        ratios[i]++;
      }
      const totalRatio = ratios.reduce((prev, curr) => prev + curr, 0);
      if (totalRatio > maxTotal) {
        const ratio = maxTotal / totalRatio;
        return ratios.map(val => Math.floor(val * ratio));
      } else if (totalRatio < minTotal) {
        const ratio = minTotal / totalRatio;
        return ratios.map(val => Math.floor(val * ratio));
      } else {
        return ratios.map(val =>
          Math.max(Math.min(val, maxRatio), minRatio)
        );
      }
    }
  },
  watch: {
    total(newVal) {
      if (newVal > this.maxTotal) {
        this.total = this.maxTotal;
        return;
      } else if (newVal < this.minTotal) {
        this.total = this.minTotal;
        return;
      }
      this.updateColumnRatio();
    },
    maxRatio(newVal) {
      if (newVal < this.minRatio) {
        this.maxRatio = this.minRatio;
        return;
      }
      this.updateMinMaxTotal();
      this.updateColumnRatio();
    },
    minRatio(newVal) {
      if (newVal > this.maxRatio) {
        this.minRatio = this.maxRatio;
        return;
      }
      this.updateMinMaxTotal();
      this.update