创建一个 Vue 2 三开关组件 ThreeStateSwitch

创建一个 Vue 2 三开关组件 ThreeStateSwitch，它支持：

三个状态：关闭（off）、慢速（slow）、快速（fast）
动画过渡：使用 CSS transition 和 cubic-bezier 实现平滑滑块移动
交互行为：点击切换状态，并触发 input 和 change 事件
禁用状态：可通过 disabled 属性控制是否可交互

效果展示：

ThreeStateSwitch组件

javascript 复制代码

// ThreeStateSwitch.vue
<template>
  <div class="three-state-switch" :class="{ 'is-disabled': disabled }">
    <div class="switch-track" >
      <div class="switch-thumb" :style="{ transform: thumbTransform }"></div>
      <div class="switch-labels">
        <span :class="{ active: value === 'off' }"  @click="toggle('off')">关闭</span>
        <span :class="{ active: value === 'slow' }"  @click="toggle('slow')">慢速</span>
        <span :class="{ active: value === 'fast' }"  @click="toggle('fast')">快速</span>
      </div>
    </div>
  </div>
</template>

<script>
export default {
  name: 'ThreeStateSwitch',
  props: {
    value: {
      type: String,
      default: 'off',
      validator: (val) => ['off', 'slow', 'fast'].includes(val)
    },
    disabled: {
      type: Boolean,
      default: false
    }
  },
  computed: {
    thumbTransform() {
      let index = 0;
      if (this.value === 'slow') index = 1;
      if (this.value === 'fast') index = 2;
      // Calculate translateX for smooth transition
      const positions = ['15%', '145%', '275%'];
      return `translateX(${positions[index]})`;
    }
  },
  methods: {
    toggle(status) {
      if (this.disabled) return;
      const states = ['off', 'slow', 'fast'];
      const currentIndex = states.indexOf(status);
      const newValue = states[currentIndex];
      this.$emit('input', newValue);
      this.$emit('change', newValue);
    }
  }
};
</script>

<style scoped>
.three-state-switch {
  display: inline-block;
  position: relative;
}

.switch-track {
  width: 100px;
  height: 30px;
  background-color: #dcdfe6;
  border-radius: 15px;
  position: relative;
  cursor: pointer;
  transition: background-color 0.3s;
  box-sizing: border-box;
}

.switch-track:hover:not(.is-disabled) {
  background-color: #bcbcbc;
}

.is-disabled .switch-track {
  opacity: 0.6;
  cursor: not-allowed;
}

.switch-thumb {
  width: 26px;
  height: 26px;
  background-color: white;
  border-radius: 50%;
  position: absolute;
  top: 2px;
  transition: transform 0.3s cubic-bezier(0.68, -0.55, 0.265, 1.55); /* Smooth easing */
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.12);
}

.switch-labels {
  position: absolute;
  width: 100%;
  height: 100%;
  display: flex;
  justify-content: space-around;
  align-items: center;
  color: #edf0f6;
  font-size: 12px;
  
}

.switch-labels span {
  transition: color 0.3s;
  z-index: 1;
}

.switch-labels span.active {
  color:#159a8d;
  font-weight: bold;
}

/* Active track background */
.three-state-switch .switch-track {
  background-color:#159a8d;
}

.three-state-switch .switch-track:hover:not(.is-disabled) {
  background-color: #29c3b4;
}
</style>

使用方法示例

javascript 复制代码

<template>
  <div>
    <ThreeStateSwitch v-model="mode" />
    <p>当前状态: {{ mode }}</p>
  </div>
</template>

<script>
import ThreeStateSwitch from './components/ThreeStateSwitch.vue';

export default {
  components: { ThreeStateSwitch },
  data() {
    return {
      mode: 'off' // 初始状态
    };
  }
};
</script>

特性说明：

滑块在三个位置之间平滑移动（关闭、慢速、快速）
标签颜色随当前状态高亮显示
背景色根据激活状态变化（蓝色背景）
支持 v-model 双向绑定
支持 disabled 属性禁用交互
支持 @change 事件监听状态变更