分割面板在日常开发中经常使用，可将一片区域，分割为可以拖拽整宽度或高度的两部分区域。模仿iview的分割面板组件，用angular实现该功能，支持拖拽和[(ngModel)]双向绑定的方式控制区域的展示收起和拖拽功能。

module.ts

ts
import { CommonModule } from "@angular/common";
import { NgModule } from "@angular/core";
import { TlShrinkSplitterComponent } from "./shrink-splitter.component";
import{NzToolTipModule} from "ng-zorro-antd/tooltip"

const COMMENT = [TlShrinkSplitterComponent];

@NgModule({
  declarations: [...COMMENT],
  exports: [...COMMENT],
  imports: [
    CommonModule,
    NzToolTipModule,
  ]
})
export class TlShrinkSplitterModule {}

component.ts

import { AfterContentInit, AfterViewInit, ChangeDetectorRef, Component, ContentChildren, ElementRef, EventEmitter, forwardRef, Input, OnInit, Output, QueryList, TemplateRef, ViewChild } from "@angular/core";
import { ControlValueAccessor, NG_VALUE_ACCESSOR } from "@angular/forms";
import { TlTemplateDirective } from "topdsm-lib/common"
import { isFalsy } from "topdsm-lib/core/util";
import { off, on } from "./util";

@Component({
    selector: "tl-shrink-splitter",
    templateUrl: "./shrink-splitter.component.html",
    providers: [
        {
            provide: NG_VALUE_ACCESSOR,
            useExisting: forwardRef(() => TlShrinkSplitterComponent),
            multi: true
        }
    ],
    host: {
        class: "tl-shrink-splitter",
        '[class.expand]': 'tlExpand',
        '[class.contract]': '!tlExpand',
        '[class.contract-left]': 'tlColsedMode === "left"',
        '[class.contract-right]': 'tlColsedMode === "right"',
        '[class.contract-top]': 'tlColsedMode === "top"',
        '[class.contract-bottom]': 'tlColsedMode === "bottom"',
        '[style.z-index]': 'tlZIndex',
    }
})
export class TlShrinkSplitterComponent implements OnInit, AfterContentInit, AfterViewInit, ControlValueAccessor {

    prefix = "tl-shrink-splitter"
    offset = 0
    oldOffset: number | string = 0
    isMoving = false
    initOffset = 0

    _value: number | string = 0.5
    isOpen = true

    @Input()
    tlZIndex = 10

    // @Input()
    // tlMode: "horizontal" | "vertical" = "horizontal"

    /** 是否展示收起icon */
    @Input()
    tlShowExpandIcon = true

    /** 收起容器模式，上下左右哪一个容器应用收起展开的状态 */
    @Input()
    tlColsedMode: "left" | "right" | "top" | "bottom" = "left"

    @Input()
    tlMin = "40px"

    @Input()
    tlMax = "40px"

    @Input()
    tlExpandTooltipContent = ""

    @Input()
    tlContractTooltipContent = ""

    get value() {
        return this._value
    }

    set value(val: number | string) {
        this._value = val
        this.onChange(val)
        this.computeOffset()
    }

    expandValueCache: string | number = 0

    /** 展开状态 */
    get tlExpand() {
        return this.isOpen;
    }

    @Input()
    set tlExpand(val: boolean) {
        if (val !== this.isOpen) {
            this.isOpen = val;
            this.tlExpandChange.emit(val);
            this.changeExpand(val)
        }
    }

    /** 容器展开状态切换 */
    changeExpand(status: boolean) {
        if (!status) {
            // 收起
            this.expandValueCache = this.value
            if (this.tlColsedMode === "left") {
                this.value = 0
            } else if (this.tlColsedMode === "right") {
                this.value = 1
            } else if (this.tlColsedMode === "top") {
                this.value = 0
            } else if (this.tlColsedMode === "bottom") {
                this.value = 1
            }
        } else {
            // 展开
            this.value = this.expandValueCache
            this.expandValueCache = 0
        }
    }

    /** 展开收缩切换事件 */
    @Output() readonly tlExpandChange = new EventEmitter<boolean>();

    @Output() readonly onMoveStart = new EventEmitter();
    @Output() readonly onMoving = new EventEmitter<MouseEvent>();
    @Output() readonly onMoveEnd = new EventEmitter();

    expandChange(e: MouseEvent) {
        e.stopPropagation();
        e.preventDefault()
        this.tlExpand = !this.isOpen
    }


    @ContentChildren(TlTemplateDirective)
    templates?: QueryList<TlTemplateDirective>

    leftTemplate?: TemplateRef<void> | null = null

    rightTemplate?: TemplateRef<void> | null = null

    topTemplate?: TemplateRef<void> | null = null

    bottomTemplate?: TemplateRef<void> | null = null

    @ViewChild('outerWrapper')
    outerWrapper: ElementRef;


    get isHorizontal() {
        //return this.tlMode === 'horizontal';
        return this.tlColsedMode === "left" || this.tlColsedMode === "right"
    }
    get computedMin() {
        return this.getComputedThresholdValue('tlMin');
    }
    get computedMax() {
        return this.getComputedThresholdValue('tlMax');
    }
    get anotherOffset() {
        return 100 - this.offset;
    }

    get valueIsPx() {
        return typeof this.value === 'string';
    }
    get offsetSize() {
        return this.isHorizontal ? 'offsetWidth' : 'offsetHeight';
    }

    get paneClasses() {
        let classes = {}
        classes[`${this.prefix}-pane`] = true
        classes[`${this.prefix}-pane-moving`] = this.isMoving
        return classes
    }

    /** 展开收起触发器icon */
    get triggrrClass() {
        let classes = {}
        if (this.tlColsedMode === "left" && this.isOpen) {
            classes["icon-caret-left"] = true
        } else if (this.tlColsedMode === "left" && !this.isOpen) {
            classes["icon-caret-right"] = true
        } else if (this.tlColsedMode === "right" && this.isOpen) {
            classes["icon-caret-right"] = true
        } else if (this.tlColsedMode === "right" && !this.isOpen) {
            classes["icon-caret-left"] = true
        } else if (this.tlColsedMode === "top" && this.isOpen) {
            classes["icon-caret-left"] = true
        } else if (this.tlColsedMode === "top" && !this.isOpen) {
            classes["icon-caret-right"] = true
        } else if (this.tlColsedMode === "bottom" && this.isOpen) {
            classes["icon-caret-right"] = true
        } else if (this.tlColsedMode === "bottom" && !this.isOpen) {
            classes["icon-caret-left"] = true
        }
        return classes
    }

    get tooltipPosition() {
        let position = "right"
        if (this.tlColsedMode === "right" && !this.isOpen) {
            position = "left"
        }
        return position
    }

    get tooltipContent() {
        let tooltip = ""
        if (this.tlColsedMode === "left" && this.isOpen) {
            tooltip = isFalsy(this.tlExpandTooltipContent) ? "收起左侧内容" : this.tlExpandTooltipContent
        } else if (this.tlColsedMode === "left" && !this.isOpen) {
            tooltip = isFalsy(this.tlContractTooltipContent) ? "展开左侧内容" : this.tlContractTooltipContent
        } else if (this.tlColsedMode === "right" && this.isOpen) {
            tooltip = isFalsy(this.tlExpandTooltipContent) ? "收起右侧内容" : this.tlExpandTooltipContent
        } else if (this.tlColsedMode === "right" && !this.isOpen) {
            tooltip = isFalsy(this.tlContractTooltipContent) ? "展开右侧内容" : this.tlContractTooltipContent
        } else if (this.tlColsedMode === "top" && this.isOpen) {
            tooltip = isFalsy(this.tlExpandTooltipContent) ? "收起顶部内容" : this.tlExpandTooltipContent
        } else if (this.tlColsedMode === "top" && !this.isOpen) {
            tooltip = isFalsy(this.tlContractTooltipContent) ? "展开顶部内容" : this.tlContractTooltipContent
        } else if (this.tlColsedMode === "bottom" && this.isOpen) {
            tooltip = isFalsy(this.tlExpandTooltipContent) ? "收起底部内容" : this.tlExpandTooltipContent
        } else if (this.tlColsedMode === "bottom" && !this.isOpen) {
            tooltip = isFalsy(this.tlContractTooltipContent) ? "展开底部内容" : this.tlContractTooltipContent
        }
        return tooltip
    }

    px2percent(numerator: string | number, denominator: string | number) {
        return parseFloat(numerator + "") / parseFloat(denominator + "");
    }


    computeOffset() {
        this.offset = (this.valueIsPx ? this.px2percent(this.value as string, this.outerWrapper.nativeElement[this.offsetSize]) : this.value) as number * 10000 / 100
    }

    getComputedThresholdValue(type) {
        let size = this.outerWrapper.nativeElement[this.offsetSize];
        if (this.valueIsPx) return typeof this[type] === 'string' ? this[type] : size * this[type];
        else return typeof this[type] === 'string' ? this.px2percent(this[type], size) : this[type];
    }
    getMin(value1, value2) {
        if (this.valueIsPx) return `${Math.min(parseFloat(value1), parseFloat(value2))}px`;
        else return Math.min(value1, value2);
    }
    getMax(value1, value2) {
        if (this.valueIsPx) return `${Math.max(parseFloat(value1), parseFloat(value2))}px`;
        else return Math.max(value1, value2);
    }

    getAnotherOffset(value) {
        let res: string | number = 0;
        if (this.valueIsPx) res = `${this.outerWrapper.nativeElement[this.offsetSize] - parseFloat(value)}px`;
        else res = 1 - value;
        return res;
    }

    handleMove = (e) => {
        let pageOffset = this.isHorizontal ? e.pageX : e.pageY;
        let offset = pageOffset - this.initOffset;
        let outerWidth = this.outerWrapper.nativeElement[this.offsetSize];
        let value: string | number = ""
        if (this.valueIsPx) {
            value = `${parseFloat(this.oldOffset as string) + offset}px`
        } else {
            value = this.px2percent(outerWidth * (this.oldOffset as number) + offset, outerWidth)
        }
        let anotherValue = this.getAnotherOffset(value);
        if (parseFloat(value + "") <= parseFloat(this.computedMin + "")) value = this.getMax(value, this.computedMin);
        if (parseFloat(anotherValue + "") <= parseFloat(this.computedMax)) value = this.getAnotherOffset(this.getMax(anotherValue, this.computedMax));
        e.atMin = this.value === this.computedMin;
        e.atMax = this.valueIsPx ? this.getAnotherOffset(this.value) === this.computedMax : (this.getAnotherOffset(this.value) as number).toFixed(5) === this.computedMax.toFixed(5);
        this.value = value
        this.onMoving.emit(e)
    }

    handleUp = (e) => {
        this.isMoving = false;
        off(document, 'mousemove', this.handleMove);
        off(document, 'mouseup', this.handleUp);
        this.onMoveEnd.emit()
    }

    onTriggerMouseDown(e) {
        this.initOffset = this.isHorizontal ? e.pageX : e.pageY;
        this.oldOffset = this.value;
        this.isMoving = true;
        on(document, 'mousemove', this.handleMove);
        on(document, 'mouseup', this.handleUp);
        this.onMoveStart.emit()
    }

    constructor(private cdr: ChangeDetectorRef) { }

    ngOnInit(): void {
        console.log("ngOnInit");
    }

    ngAfterViewInit(): void {
        console.log("ngAfterViewInit");
        this.computeOffset()
    }

    ngAfterContentInit() {
        this.templates?.forEach((item) => {
            switch (item.getType()) {
                case 'left':
                    this.leftTemplate = item.template;
                    break;
                case 'right':
                    this.rightTemplate = item.template;
                    break;
                case 'top':
                    this.topTemplate = item.template;
                    break;
                case 'bottom':
                    this.bottomTemplate = item.template;
                    break;
                default:
                    this.leftTemplate = item.template;
                    break;
            }
        });

    }

    // 输入框数据变化时
    onChange: (value: any) => void = () => null;
    onTouched: () => void = () => null;

    writeValue(val: number | string): void {
        if (val !== this.value) {
            this.value = val
            this.computeOffset();
            this.cdr.markForCheck();
        }
    }
    // UI界面值发生更改，调用注册的回调函数
    registerOnChange(fn: any): void {
        this.onChange = fn;
    }

    // 在blur（等失效事件），调用注册的回调函数
    registerOnTouched(fn: any): void {
        this.onTouched = fn;
    }

    // 设置禁用状态
    setDisabledState?(isDisabled: boolean): void {

    }
}

TlTemplateDirective指令实现

ts
import { Directive, Input, TemplateRef, ViewContainerRef } from "@angular/core";
import { NzSafeAny } from "topdsm-lib/core/types";

@Directive({
  selector: '[tlTemplate]'
})
export class TlTemplateDirective {

  @Input('tlTemplate')
  name: string = "default"

  // @Input()
  // type: string = ""

  constructor(private viewContainer: ViewContainerRef, public template: TemplateRef<NzSafeAny>) {
    //this.template = templateRef;
  }
  ngOnInit(): void {
    this.viewContainer.createEmbeddedView(this.template)
  }
  getType() {
    return this.name;
  }
}

事件绑定、解绑

export const on = (function() {
    if (document.addEventListener) {
        return function(element, event, handler) {
            if (element && event && handler) {
                element.addEventListener(event, handler, false);
            }
        };
    } else {
        return function(element, event, handler) {
            if (element && event && handler) {
                element.attachEvent('on' + event, handler);
            }
        };
    }
})();

export const off = (function() {
    if (document.removeEventListener) {
        return function(element, event, handler) {
            if (element && event) {
                element.removeEventListener(event, handler, false);
            }
        };
    } else {
        return function(element, event, handler) {
            if (element && event) {
                element.detachEvent('on' + event, handler);
            }
        };
    }
})();

component.html

html
<div [ngClass]="prefix + '-wrapper'" #outerWrapper>
    <div [ngClass]="prefix + '-horizontal'" *ngIf="isHorizontal; else verticalSlot">
        <div class="left-pane" [ngStyle]="{right: anotherOffset + '%'}" [ngClass]="paneClasses">
            <ng-container *ngTemplateOutlet="leftTemplate"></ng-container>
        </div>
        <div [ngClass]="prefix + '-trigger-con'" [ngStyle]="{left: offset + '%'}" (mousedown)="onTriggerMouseDown($event)">
            <div ngClass="tl-shrink-splitter-trigger tl-shrink-splitter-trigger-vertical" >
                <!-- <span class="tl-shrink-splitter-trigger-bar-con vertical" [ngClass]="triggrrClass" (mousedown)="expandChange($event)" [tTooltip]="tooltipContent" [tooltipPosition]="tooltipPosition" *ngIf="tlShowExpandIcon"></span> -->
                <span class="tl-shrink-splitter-trigger-bar-con vertical" [ngClass]="triggrrClass" (mousedown)="expandChange($event)" nz-tooltip [nzTooltipTitle]="tooltipContent" [nzTooltipPlacement]="tooltipPosition" *ngIf="tlShowExpandIcon"></span>
            </div>
        </div>
        <div class="right-pane" [ngStyle]="{left: offset + '%'}" [ngClass]="paneClasses">
            <ng-container *ngTemplateOutlet="rightTemplate"></ng-container>
        </div>
    </div>
    
    <ng-template #verticalSlot>
        <div [ngClass]="prefix + '-vertical'" >
            <div class="top-pane" [ngStyle]="{bottom: anotherOffset + '%'}" [ngClass]="paneClasses">
                <ng-container *ngTemplateOutlet="topTemplate"></ng-container>
            </div>
            <div [ngClass]="prefix + '-trigger-con'" [ngStyle]="{top: offset + '%'}" (mousedown)="onTriggerMouseDown($event)">
                <div ngClass="tl-shrink-splitter-trigger tl-shrink-splitter-trigger-horizontal" >
                    <!-- <span class="tl-shrink-splitter-trigger-bar-con horizontal" [ngClass]="triggrrClass" (mousedown)="expandChange($event)" [tTooltip]="tooltipContent" [tooltipPosition]="tooltipPosition" *ngIf="tlShowExpandIcon"></span> -->
                    <span class="tl-shrink-splitter-trigger-bar-con horizontal" [ngClass]="triggrrClass" (mousedown)="expandChange($event)" nz-tooltip [nzTooltipTitle]="tooltipContent" [nzTooltipPlacement]="tooltipPosition" *ngIf="tlShowExpandIcon"></span>
                </div>
            </div>
            <div class="bottom-pane" [ngStyle]="{top: offset + '%'}" [ngClass]="paneClasses">
                <ng-container *ngTemplateOutlet="bottomTemplate"></ng-container>
            </div>
        </div>
    </ng-template>
</div>

component.less

less
@split-prefix-cls: ~"tl-shrink-splitter";
@trigger-bar-background: rgba(23, 35, 61, 0.25);
@trigger-background: #f8f8f9;
@trigger-width: 8px;
@trigger-bar-width: 4px;
@trigger-bar-offset: (@trigger-width - @trigger-bar-width) / 2;
@trigger-bar-interval: 3px;
@trigger-bar-weight: 1px;
@trigger-bar-con-height: 20px;
.tl-shrink-splitter{
    position: relative;
    height: 100%;
    width: 100%;
}
.tl-shrink-splitter-wrapper{
    position: relative;
    height: 100%;
    width: 100%;
}

.@{split-prefix-cls}{
    background-color: #fff;
    border: 1px solid #dee2e6;
    &-pane{
        position: absolute;
        transition: all .3s ease-in;
        padding: 8px;

        &.tl-shrink-splitter-pane-moving{
            transition: none;
        }
        &.left-pane, &.right-pane {
            top: 0;
            bottom: 0;
        }
        &.left-pane {
            left: 0;
        }
        &.right-pane {
            right: 0;
            padding-left: 16px;
        }
        &.top-pane, &.bottom-pane {
            left: 0;
            right: 0;
        }
        &.top-pane {
            top: 0;
        }
        &.bottom-pane {
            bottom: 0;
            padding-top: 16px;
        }
        &-moving{
            -webkit-user-select: none;
            -moz-user-select: none;
            -ms-user-select: none;
            user-select: none;
        }
    }

    &-trigger{
        border: 1px solid #dcdee2;
        &-con {
            position: absolute;
            transform: translate(-50%, -50%);
            z-index: 10;
        }
        &-bar-con {
            position: absolute;
            overflow: hidden;
            &:hover{
                color: #000 !important;
            }
            &.vertical {
                top: 50%;
                left: -6px;
                width: 20px;
                height: @trigger-bar-con-height;
                background-color: #fff;
                border: 1px solid #ccc;
                border-radius: 50%;
                display: flex;
                align-items: center;
                justify-content: center;
                color: #b2b2b2;
                font-size: 14px;
                cursor: pointer;
            }
            &.horizontal {
                left: 50%;
                top: -4px;
                width: @trigger-bar-con-height;
                height: 20px;
                //transform: translate(-50%, 0);
                background-color: #fff;
                border: 1px solid #ccc;
                border-radius: 50%;
                display: flex;
                align-items: center;
                justify-content: center;
                color: #b2b2b2;
                font-size: 14px;
                cursor: pointer;
            }
        }
        &-vertical {
            width: @trigger-width;
            height: 100%;
            background: @trigger-background;
            border-top: none;
            border-bottom: none;
            cursor: col-resize;
            .@{split-prefix-cls}-trigger-bar {
                width: @trigger-bar-width;
                height: 1px;
                background: @trigger-bar-background;
                float: left;
                margin-top: @trigger-bar-interval;
            }
        }
        &-horizontal {
            height: @trigger-width;
            width: 100%;
            background: @trigger-background;
            border-left: none;
            border-right: none;
            cursor: row-resize;
            .@{split-prefix-cls}-trigger-bar {
                height: @trigger-bar-width;
                width: 1px;
                background: @trigger-bar-background;
                float: left;
                margin-right: @trigger-bar-interval;
            }
        }
    }

    &-horizontal {
        .@{split-prefix-cls}-trigger-con {
            top: 50%;
            height: 100%;
            width: 0;
        }
    }
    &-vertical {
        .@{split-prefix-cls}-trigger-con {
            left: 50%;
            height: 0;
            width: 100%;
        }
    }
}


.tl-shrink-splitter.contract{
    .tl-shrink-splitter-trigger-vertical{
        width: 0;
        padding-left: 0;
    }
    .tl-shrink-splitter-trigger-horizontal{
        height: 0;
        padding-top: 0;
    }
    .tl-shrink-splitter-trigger{
        border: 0;
    }

    &.contract-left{
        .tl-shrink-splitter-pane.left-pane{
            width: 0;
            padding: 0;
            overflow: hidden;
        }
        .right-pane{
            padding-left: 8px;
        }
    }

    .tl-shrink-splitter-trigger-bar-con{
        &.vertical{
            left: -6px;
        }
    }
    
    &.contract-right{
        .tl-shrink-splitter-trigger-bar-con{
            &.vertical{
                left: -16px;
            }
        }
    }

    &.contract-top{
        .tl-shrink-splitter-pane.top-pane{
            overflow: hidden;
            height: 0;
            padding: 0;
        }
        .bottom-pane{
            padding-top: 8px;
        }
        .tl-shrink-splitter-trigger-bar-con.horizontal{
            transform: rotate(90deg);
        }
    }

    &.contract-bottom{
        .tl-shrink-splitter-trigger-bar-con{
            &.horizontal{
                top: -16px;
            }
        }
        .tl-shrink-splitter-pane.bottom-pane{
            overflow: hidden;
            height: 0;
            padding: 0;
        }
        .top-pane{
            padding-top: 8px;
        }
        .tl-shrink-splitter-trigger-bar-con.horizontal{
            transform: rotate(90deg);
        }
    }
}
.tl-shrink-splitter.expand{
    .tl-shrink-splitter-trigger-bar-con{
        &.vertical{
            left: -8px;
        }
    }

    &.contract-top{
        .tl-shrink-splitter-trigger-bar-con.horizontal{
            transform: rotate(90deg);
        }
    }

    &.contract-bottom{
        .tl-shrink-splitter-trigger-bar-con.horizontal{
            transform: rotate(90deg);
        }
    }
}

页面效果