shenweishi/node_modules/@vant/weapp/dist/slider/index.js

import { VantComponent } from '../common/component';
import { touch } from '../mixins/touch';
import { canIUseModel } from '../common/version';
import { getRect } from '../common/utils';
VantComponent({
    mixins: [touch],
    props: {
        range: Boolean,
        disabled: Boolean,
        useButtonSlot: Boolean,
        activeColor: String,
        inactiveColor: String,
        max: {
            type: Number,
            value: 100,
        },
        min: {
            type: Number,
            value: 0,
        },
        step: {
            type: Number,
            value: 1,
        },
        value: {
            type: null,
            value: 0,
            observer(val) {
                if (val !== this.value) {
                    this.updateValue(val);
                }
            },
        },
        barHeight: null,
    },
    created() {
        this.updateValue(this.data.value);
    },
    methods: {
        onTouchStart(event) {
            if (this.data.disabled)
                return;
            const { index } = event.currentTarget.dataset;
            if (typeof index === 'number') {
                this.buttonIndex = index;
            }
            this.touchStart(event);
            this.startValue = this.format(this.value);
            this.newValue = this.value;
            if (this.isRange(this.newValue)) {
                this.startValue = this.newValue.map((val) => this.format(val));
            }
            else {
                this.startValue = this.format(this.newValue);
            }
            this.dragStatus = 'start';
        },
        onTouchMove(event) {
            if (this.data.disabled)
                return;
            if (this.dragStatus === 'start') {
                this.$emit('drag-start');
            }
            this.touchMove(event);
            this.dragStatus = 'draging';
            getRect(this, '.van-slider').then((rect) => {
                const diff = (this.deltaX / rect.width) * this.getRange();
                if (this.isRange(this.startValue)) {
                    this.newValue[this.buttonIndex] =
                        this.startValue[this.buttonIndex] + diff;
                }
                else {
                    this.newValue = this.startValue + diff;
                }
                this.updateValue(this.newValue, false, true);
            });
        },
        onTouchEnd() {
            if (this.data.disabled)
                return;
            if (this.dragStatus === 'draging') {
                this.updateValue(this.newValue, true);
                this.$emit('drag-end');
            }
        },
        onClick(event) {
            if (this.data.disabled)
                return;
            const { min } = this.data;
            getRect(this, '.van-slider').then((rect) => {
                const value = ((event.detail.x - rect.left) / rect.width) * this.getRange() + min;
                if (this.isRange(this.value)) {
                    const [left, right] = this.value;
                    const middle = (left + right) / 2;
                    if (value <= middle) {
                        this.updateValue([value, right], true);
                    }
                    else {
                        this.updateValue([left, value], true);
                    }
                }
                else {
                    this.updateValue(value, true);
                }
            });
        },
        isRange(val) {
            const { range } = this.data;
            return range && Array.isArray(val);
        },
        handleOverlap(value) {
            if (value[0] > value[1]) {
                return value.slice(0).reverse();
            }
            return value;
        },
        updateValue(value, end, drag) {
            if (this.isRange(value)) {
                value = this.handleOverlap(value).map((val) => this.format(val));
            }
            else {
                value = this.format(value);
            }
            this.value = value;
            this.setData({
                barStyle: `
          width: ${this.calcMainAxis()};
          left: ${this.isRange(value) ? `${value[0]}%` : 0};
          ${drag ? 'transition: none;' : ''}
        `,
            });
            if (drag) {
                this.$emit('drag', { value });
            }
            if (end) {
                this.$emit('change', value);
            }
            if ((drag || end) && canIUseModel()) {
                this.setData({ value });
            }
        },
        getScope() {
            return Number(this.data.max) - Number(this.data.min);
        },
        getRange() {
            const { max, min } = this.data;
            return max - min;
        },
        // 计算选中条的长度百分比
        calcMainAxis() {
            const { value } = this;
            const { min } = this.data;
            const scope = this.getScope();
            if (this.isRange(value)) {
                return `${((value[1] - value[0]) * 100) / scope}%`;
            }
            return `${((value - Number(min)) * 100) / scope}%`;
        },
        format(value) {
            const { max, min, step } = this.data;
            return Math.round(Math.max(min, Math.min(value, max)) / step) * step;
        },
    },
});