u-message-input

<template>
  <view class="u-char-box">
    <view class="u-char-flex">
      <input
        :disabled="disabledKeyboard"
        :value="valueModel"
        type="number"
        :focus="focus"
        :maxlength="maxlength"
        class="u-input"
        @input="getVal"
      />
      <view v-for="(item, index) in maxlength" :key="index">
        <view
          :class="[breathe && charArrLength == index ? 'u-breathe' : '', 'u-char-item',
				charArrLength === index && mode == 'box' ? 'u-box-active' : '',
				mode === 'box' ? 'u-box' : '']"
          :style="{
					fontWeight: bold ? 'bold' : 'normal',
					fontSize: fontSize + 'rpx',
					width: width + 'rpx',
					height: width + 'rpx',
					color: inactiveColor
				}"
        >
          <view
            class="u-placeholder-line"
            :style="{
							display: charArrLength === index ? 'block' : 'none',
							height: width * 0.5 +'rpx'
						}"
            v-if="mode !== 'middleLine'"
          ></view>
          <view
            v-if="mode === 'middleLine' && charArrLength <= index"
            :class="[breathe && charArrLength == index ? 'u-breathe' : '', charArrLength === index ? 'u-middle-line-active' : '']"
            class="u-middle-line"
            :style="{height: bold ? '4px' : '2px', background: charArrLength === index ? activeColor : inactiveColor}"
          ></view>
          <view
            v-if="mode === 'bottomLine'"
            :class="[breathe && charArrLength == index ? 'u-breathe' : '', charArrLength === index ? 'u-buttom-line-active' : '']"
            class="u-bottom-line"
            :style="{height: bold ? '4px' : '2px', background: charArrLength === index ? activeColor : inactiveColor}"
          ></view>
          <block v-if="!dotFill">{{ charArr[index] ? charArr[index] : ''}}</block>
          <block v-else>
            <text class="u-dot">{{ charArr[index] ? '●' : ''}}</text>
          </block>
        </view>
      </view>
    </view>
  </view>
</template>

<script>
/**
 * messageInput 验证码输入框
 * @description 该组件一般用于验证用户短信验证码的场景，也可以结合uView的键盘组件使用
 * @tutorial https://www.uviewui.com/components/messageInput.html
 * @property {String Number} maxlength 输入字符个数（默认4）
 * @property {Boolean} dot-fill 是否用圆点填充（默认false）
 * @property {String} mode 模式选择，见上方"基本使用"说明（默认box）
 * @property {String Number} value 预置值
 * @property {Boolean} breathe 是否开启呼吸效果，见上方说明（默认true）
 * @property {Boolean} focus 是否自动获取焦点（默认false）
 * @property {Boolean} bold 字体和输入横线是否加粗（默认true）
 * @property {String Number} font-size 字体大小，单位rpx（默认60）
 * @property {String} active-color 当前激活输入框的样式（默认#2979ff）
 * @property {String} inactive-color 非激活输入框的样式，文字颜色同此值（默认#606266）
 * @property {String | Number} width 输入框宽度，单位rpx，高等于宽（默认80）
 * @property {Boolean} disabled-keyboard 禁止点击输入框唤起系统键盘（默认false）
 * @event {Function} change 输入内容发生改变时触发，具体见官网说明
 * @event {Function} finish 输入字符个数达maxlength值时触发，见官网说明
 * @example <u-message-input mode="bottomLine"></u-message-input>
 */
export default {
  name: 'u-message-input',
  props: {
    // 最大输入长度
    maxlength: {
      type: [Number, String],
      default: 4
    },
    // 是否用圆点填充
    dotFill: {
      type: Boolean,
      default: false
    },
    // 显示模式，box-盒子模式，bottomLine-横线在底部模式，middleLine-横线在中部模式
    mode: {
      type: String,
      default: 'box'
    },
    // 预置值
    value: {
      type: [String, Number],
      default: ''
    },
    // 当前激活输入item，是否带有呼吸效果
    breathe: {
      type: Boolean,
      default: true
    },
    // 是否自动获取焦点
    focus: {
      type: Boolean,
      default: false
    },
    // 字体是否加粗
    bold: {
      type: Boolean,
      default: false
    },
    // 字体大小
    fontSize: {
      type: [String, Number],
      default: 30
    },
    // 激活样式
    activeColor: {
      type: String,
      default: '#2979ff'
    },
    // 未激活的样式
    inactiveColor: {
      type: String,
      default: '#606266'
    },
    // 输入框的大小，单位rpx，宽等于高
    width: {
      type: [Number, String],
      default: '40'
    },
    // 是否隐藏原生键盘，如果想用自定义键盘的话，需设置此参数为true
    disabledKeyboard: {
      type: Boolean,
      default: false
    }
  },
  watch: {
    maxlength: {
      // 此值设置为true，会在组件加载后无需maxlength变化就会执行一次本监听函数，无需再created生命周期中处理
      immediate: true,
      handler(val) {
        this.maxlength = Number(val)
      }
    },
    value: {
      immediate: true,
      handler(val) {
        // 转为字符串
        val = String(val)
        // 超出部分截掉
        this.valueModel = val.substring(0, this.maxlength)
      }
    }
  },
  data() {
    return {
      valueModel: ''
    }
  },
  computed: {
    // 是否显示呼吸灯效果
    animationClass() {
      return index => {
        if (this.breathe && this.charArr.length == index) return 'u-breathe'
        else return ''
      }
    },
    // 用于显示字符
    charArr() {
      return this.valueModel.split('')
    },
    charArrLength() {
      return this.charArr.length
    }
  },
  methods: {
    getVal(e) {
      let { value } = e.detail
      this.valueModel = value
      // 判断长度是否超出了maxlength值，理论上不会发生，因为input组件设置了maxlength属性值
      if (String(value).length > this.maxlength) return
      // 未达到maxlength之前，发送change事件，达到后发送finish事件
      this.$emit('change', value)
      if (String(value).length == this.maxlength) {
        this.$emit('finish', value)
      }
    }
  }
}
</script>

<style scoped lang="scss">
@import '../../libs/css/style.components.scss';

@keyframes breathe {
  0% {
    opacity: 0.3;
  }

  50% {
    opacity: 1;
  }

  100% {
    opacity: 0.3;
  }
}

.u-char-box {
  text-align: center;
}

.u-char-flex {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  position: relative;
}

.u-input {
  position: absolute;
  top: 0;
  left: -100%;
  width: 200%;
  height: 100%;
  text-align: left;
  z-index: 9;
  opacity: 0;
  background: none;
}

.u-char-item {
  position: relative;
  width: 45rpx;
  height: 45rpx;
  margin: 10rpx 10rpx;
  font-size: 30rpx;
  font-weight: bold;
  color: $u-main-color;
  line-height: 45rpx;
  display: flex;
  justify-content: center;
  align-items: center;
}

.u-middle-line {
  border: none;
}

.u-box {
  box-sizing: border-box;
  border: 2rpx solid #cccccc;
  border-radius: 6rpx;
}

.u-box-active {
  overflow: hidden;
  animation-timing-function: ease-in-out;
  animation-duration: 1500ms;
  animation-iteration-count: infinite;
  animation-direction: alternate;
  border: 2rpx solid $u-type-primary;
}

.u-middle-line-active {
  background: $u-type-primary;
}

.u-breathe {
  animation: breathe 2s infinite ease;
}

.u-placeholder-line {
  display: none;
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 2rpx;
  height: 20rpx;
  background: #333333;
  animation: twinkling 1.5s infinite ease;
}

.u-animation-breathe {
  animation-name: breathe;
}

.u-dot {
  font-size: 17rpx;
  line-height: 17rpx;
}

.u-middle-line {
  height: 4px;
  background: #000000;
  width: 80%;
  position: absolute;
  border-radius: 2px;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.u-buttom-line-active {
  background: $u-type-primary;
}

.u-bottom-line {
  height: 4px;
  background: #000000;
  width: 80%;
  position: absolute;
  border-radius: 2px;
  bottom: 0;
  left: 50%;
  transform: translate(-50%);
}
</style>