CocosCreator版本:2.3.4
cocos没有List组件,所以要自己写。从cocos的example项目中找到assets/case/02_ui/05_listView的demo来改造。
自写一个虚拟列表,有垂直布局,水平布局,网格布局和Padding的List
Demo地址:https://files-cdn.cnblogs.com/files/gamedaybyday/cocos2.3.4_ListViewDemo_Grid.7z
cocos原来的LayOut做列表,有100个数据就有100个实例(左侧图)。
而虚拟列表则只有你看见的实例存在,当滑动时会循环使用。(右侧图)
List使用方法
使用方法就是在ScrollView上添加List组件即可。
List的item列表项直接放在content下,并赋值給List组件,item需要添加继承自ItemRender的对象,用于数据刷新。
代码中给List设置数据
- //设置排行榜数据
- let rankData = [];
- for(let i=0;i<100;i++){
- rankData.push({rank:i, name:"名称"});
- }
- this.rankList.setData(rankData);
源码
- // Learn TypeScript:
- // - https://docs.cocos.com/creator/manual/en/scripting/typescript.html
- // Learn Attribute:
- // - https://docs.cocos.com/creator/manual/en/scripting/reference/attributes.html
- // Learn life-cycle callbacks:
- // - https://docs.cocos.com/creator/manual/en/scripting/life-cycle-callbacks.html
- import ItemRender from "./ItemRender"
- const { ccclass, property } = cc._decorator;
- /**列表排列方式 */
- export enum ListType {
- /**水平排列 */
- Horizontal = 1,
- /**垂直排列 */
- Vertical = 2,
- /**网格排列 */
- Grid = 3
- }
- /**网格布局中的方向 */
- export enum StartAxisType {
- /**水平排列 */
- Horizontal = 1,
- /**垂直排列 */
- Vertical = 2,
- }
- /**
- * 列表
- * 根据cocos_example的listView改动而来
- * @author chenkai 2020.7.8
- * @example
- * 1.创建cocos的ScrollView组件,添加List,设置List属性即可
- *
- */
- @ccclass
- export default class List extends cc.Component {
- //==================== 属性面板 =========================
- /**列表选项 */
- @property({ type: cc.Node, tooltip: "列表项" })
- public itemRender: cc.Node = null;
- /**排列方式 */
- @property({ type: cc.Enum(ListType), tooltip: "排列方式" })
- public type: ListType = ListType.Vertical;
- /**网格布局中的方向 */
- @property({ type: cc.Enum(StartAxisType), tooltip: "网格布局中的方向", visible() { return this.type == ListType.Grid } })
- public startAxis: StartAxisType = StartAxisType.Horizontal;
- /**列表项之间X间隔 */
- @property({ type: cc.Integer, tooltip: "列表项X间隔", visible() { return (this.type == ListType.Horizontal || this.type == ListType.Grid) } })
- public spaceX: number = 0;
- /**列表项之间Y间隔 */
- @property({ type: cc.Integer, tooltip: "列表项Y间隔", visible() { return this.type == ListType.Vertical || this.type == ListType.Grid } })
- public spaceY: number = 0;
- /**上间距 */
- @property({ type: cc.Integer, tooltip: "上间距", visible() { return (this.type == ListType.Vertical || this.type == ListType.Grid) } })
- public padding_top: number = 0;
- /**下间距 */
- @property({ type: cc.Integer, tooltip: "下间距", visible() { return (this.type == ListType.Vertical || this.type == ListType.Grid) } })
- public padding_buttom: number = 0;
- /**左间距 */
- @property({ type: cc.Integer, tooltip: "左间距", visible() { return (this.type == ListType.Horizontal || this.type == ListType.Grid) } })
- public padding_left: number = 0;
- @property(cc.Integer)
- public _padding: number = 0;
- /**右间距 */
- @property({ type: cc.Integer, tooltip: "右间距", visible() { return (this.type == ListType.Horizontal || this.type == ListType.Grid) } })
- public padding_right: number = 0;
- //====================== 滚动容器 ===============================
- /**列表滚动容器 */
- public scrollView: cc.ScrollView = null;
- /**scrollView的内容容器 */
- private content: cc.Node = null;
- //======================== 列表项 ===========================
- /**列表项数据 */
- private itemDataList: Array<any> = [];
- /**应创建的实例数量 */
- private spawnCount: number = 0;
- /**存放列表项实例的数组 */
- private itemList: Array<cc.Node> = [];
- /**item的高度 */
- private itemHeight: number = 0;
- /**item的宽度 */
- private itemWidth: number = 0;
- /**存放不再使用中的列表项 */
- private itemPool: Array<cc.Node> = [];
- //======================= 计算参数 ==========================
- /**距离scrollView中心点的距离,超过这个距离的item会被重置,一般设置为 scrollVIew.height/2 + item.heigt/2 + space,因为这个距离item正好超出scrollView显示范围 */
- private halfScrollView: number = 0;
- /**上一次content的X值,用于和现在content的X值比较,得出是向左还是向右滚动 */
- private lastContentPosX: number = 0;
- /**上一次content的Y值,用于和现在content的Y值比较,得出是向上还是向下滚动 */
- private lastContentPosY: number = 0;
- /**网格行数 */
- private gridRow: number = 0;
- /**网格列数 */
- private gridCol: number = 0;
- /**刷新时间,单位s */
- private updateTimer: number = 0;
- /**刷新间隔,单位s */
- private updateInterval: number = 0.1;
- /**是否滚动容器 */
- private bScrolling: boolean = false;
- /**刷新的函数 */
- private updateFun: Function = function () { };
- onLoad() {
- this.itemHeight = this.itemRender.height;
- this.itemWidth = this.itemRender.width;
- this.scrollView = this.node.getComponent(cc.ScrollView);
- this.content = this.scrollView.content;
- this.content.anchorX = 0;
- this.content.anchorY = 1;
- this.content.removeAllChildren();
- this.scrollView.node.on("scrolling", this.onScrolling, this);
- }
- /**
- * 列表数据 (列表数据复制使用,如果列表数据改变,则需要重新设置一遍数据)
- * @param itemDataList item数据列表
- */
- public setData(itemDataList: Array<any>) {
- this.itemDataList = itemDataList.slice();
- this.updateContent();
- }
- /**计算列表的各项参数 */
- private countListParam() {
- let dataLen = this.itemDataList.length;
- if (this.type == ListType.Vertical) {
- this.scrollView.horizontal = false;
- this.scrollView.vertical = true;
- this.content.width = this.content.parent.width;
- this.content.height = dataLen * this.itemHeight + (dataLen - 1) * this.spaceY + this.padding_top + this.padding_buttom;
- this.spawnCount = Math.round(this.scrollView.node.height / (this.itemHeight + this.spaceY)) + 2; //计算创建的item实例数量,比当前scrollView容器能放下的item数量再加上2个
- this.halfScrollView = this.scrollView.node.height / 2 + this.itemHeight / 2 + this.spaceY; //计算bufferZone,item的显示范围
- this.updateFun = this.updateV;
- } else if (this.type == ListType.Horizontal) {
- this.scrollView.horizontal = true;
- this.scrollView.vertical = false;
- this.content.width = dataLen * this.itemWidth + (dataLen - 1) * this.spaceX + this.padding_left + this.padding_right;
- this.content.height = this.content.parent.height;
- this.spawnCount = Math.round(this.scrollView.node.width / (this.itemWidth + this.spaceX)) + 2;
- this.halfScrollView = this.scrollView.node.width / 2 + this.itemWidth / 2 + this.spaceX;
- this.updateFun = this.udpateH;
- } else if (this.type == ListType.Grid) {
- if (this.startAxis == StartAxisType.Vertical) {
- this.scrollView.horizontal = false;
- this.scrollView.vertical = true;
- this.content.width = this.content.parent.width;
- //如果left和right间隔过大,导致放不下一个item,则left和right都设置为0,相当于不生效
- if (this.padding_left + this.padding_right + this.itemWidth + this.spaceX > this.content.width) {
- this.padding_left = 0;
- this.padding_right = 0;
- console.error("padding_left或padding_right过大");
- }
- this.gridCol = Math.floor((this.content.width - this.padding_left - this.padding_right) / (this.itemWidth + this.spaceX));
- this.gridRow = Math.ceil(dataLen / this.gridCol);
- this.content.height = this.gridRow * this.itemHeight + (this.gridRow - 1) * this.spaceY + this.padding_top + this.padding_buttom;
- this.spawnCount = Math.round(this.scrollView.node.height / (this.itemHeight + this.spaceY)) * this.gridCol + this.gridCol * 2;
- this.halfScrollView = this.scrollView.node.height / 2 + this.itemHeight / 2 + this.spaceY;
- this.updateFun = this.updateGrid_V;
- } else if (this.startAxis == StartAxisType.Horizontal) {
- this.scrollView.horizontal = true;
- this.scrollView.vertical = false;
- //计算高间隔
- this.content.height = this.content.parent.height;
- //如果left和right间隔过大,导致放不下一个item,则left和right都设置为0,相当于不生效
- if (this.padding_top + this.padding_buttom + this.itemHeight + this.spaceY > this.content.height) {
- this.padding_top = 0;
- this.padding_buttom = 0;
- console.error("padding_top或padding_buttom过大");
- }
- this.gridRow = Math.floor((this.content.height - this.padding_top - this.padding_buttom) / (this.itemHeight + this.spaceY));
- this.gridCol = Math.ceil(dataLen / this.gridRow);
- this.content.width = this.gridCol * this.itemWidth + (this.gridCol - 1) * this.spaceX + this.padding_left + this.padding_right;
- this.spawnCount = Math.round(this.scrollView.node.width / (this.itemWidth + this.spaceX)) * this.gridRow + this.gridRow * 2;
- this.halfScrollView = this.scrollView.node.width / 2 + this.itemWidth / 2 + this.spaceX;
- this.updateFun = this.updateGrid_H;
- }
- }
- }
- /**
- * 创建列表
- * @param startIndex 起始显示的数据索引 0表示第一项
- * @param offset scrollView偏移量
- */
- private createList(startIndex: number, offset: cc.Vec2) {
- //当需要显示的数据长度 > 虚拟列表长度, 删除最末尾几个数据时,列表需要重置位置到scrollView最底端
- if (this.itemDataList.length > this.spawnCount && (startIndex + this.spawnCount - 1) >= this.itemDataList.length) {
- startIndex = this.itemDataList.length - this.spawnCount;
- offset = this.scrollView.getMaxScrollOffset();
- //当需要显示的数据长度 <= 虚拟列表长度, 隐藏多余的虚拟列表项
- } else if (this.itemDataList.length <= this.spawnCount) {
- startIndex = 0;
- }
- for (let i = 0; i < this.spawnCount; i++) {
- let item: cc.Node;
- //需要显示的数据索引在数据范围内,则item实例显示出来
- if (i + startIndex < this.itemDataList.length) {
- if (this.itemList[i] == null) {
- item = this.getItem();
- this.itemList.push(item);
- item.parent = this.content;
- } else {
- item = this.itemList[i];
- }
- //需要显示的数据索引超过了数据范围,则item实例隐藏起来
- } else {
- //item实例数量 > 需要显示的数据量
- if (this.itemList.length > (this.itemDataList.length - startIndex)) {
- item = this.itemList.pop();
- item.removeFromParent();
- this.itemPool.push(item);
- }
- continue;
- }
- let itemRender: ItemRender = item.getComponent(ItemRender);
- itemRender.itemIndex = i + startIndex;
- itemRender.data = this.itemDataList[i + startIndex];
- itemRender.dataChanged();
- if (this.type == ListType.Vertical) {
- //因为content的锚点X是0,所以item的x值是content.with/2表示居中,锚点Y是1,所以item的y值从content顶部向下是0到负无穷。所以item.y= -item.height/2时,是在content的顶部。
- item.setPosition(this.content.width / 2, -item.height * (0.5 + i + startIndex) - this.spaceY * (i + startIndex) - this.padding_top);
- } else if (this.type == ListType.Horizontal) {
- item.setPosition(item.width * (0.5 + i + startIndex) + this.spaceX * (i + startIndex) + this.padding_left, -this.content.height / 2);
- } else if (this.type == ListType.Grid) {
- if (this.startAxis == StartAxisType.Vertical) {
- var row = Math.floor((i + startIndex) / this.gridCol);
- var col = (i + startIndex) % this.gridCol;
- item.setPosition(item.width * (0.5 + col) + this.spaceX * col + this.padding_left, -item.height * (0.5 + row) - this.spaceY * row - this.padding_top);
- item.opacity = 255;
- } else if (this.startAxis == StartAxisType.Horizontal) {
- var row = (i + startIndex) % this.gridRow;
- var col = Math.floor((i + startIndex) / this.gridRow);
- item.setPosition(item.width * (0.5 + col) + this.spaceX * col + this.padding_left, -item.height * (0.5 + row) - this.spaceY * row - this.padding_top);
- item.opacity = 255;
- }
- }
- }
- this.scrollView.scrollToOffset(offset);
- }
- /**获取一个列表项 */
- private getItem() {
- if (this.itemPool.length == 0) {
- return cc.instantiate(this.itemRender);
- } else {
- return this.itemPool.pop();
- }
- }
- update(dt) {
- if (this.bScrolling == false) {
- return;
- }
- this.updateTimer += dt;
- if (this.updateTimer < this.updateInterval) {
- return;
- }
- this.updateTimer = 0;
- this.bScrolling = false;
- this.updateFun();
- }
- onScrolling() {
- this.bScrolling = true;
- }
- /**垂直排列 */
- private updateV() {
- let items = this.itemList;
- let item;
- let bufferZone = this.halfScrollView;
- let isUp = this.scrollView.content.y > this.lastContentPosY;
- let offset = (this.itemHeight + this.spaceY) * items.length;
- for (let i = 0; i < items.length; i++) {
- item = items[i];
- let viewPos = this.getPositionInView(item);
- if (isUp) {
- //item上滑时,超出了scrollView上边界,将item移动到下方复用,item移动到下方的位置必须不超过content的下边界
- if (viewPos.y > bufferZone && item.y - offset - this.padding_buttom > -this.content.height) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex + items.length;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.y = item.y - offset;
- }
- } else {
- //item下滑时,超出了scrollView下边界,将item移动到上方复用,item移动到上方的位置必须不超过content的上边界
- if (viewPos.y < -bufferZone && item.y + offset + this.padding_top < 0) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex - items.length;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.y = item.y + offset;
- }
- }
- }
- this.lastContentPosY = this.scrollView.content.y;
- }
- /**水平排列 */
- private udpateH() {
- let items = this.itemList;
- let item;
- let bufferZone = this.halfScrollView;
- let isRight = this.scrollView.content.x > this.lastContentPosX;
- let offset = (this.itemWidth + this.spaceX) * items.length;
- for (let i = 0; i < items.length; i++) {
- item = items[i];
- let viewPos = this.getPositionInView(item);
- if (isRight) {
- //item右滑时,超出了scrollView右边界,将item移动到左方复用,item移动到左方的位置必须不超过content的左边界
- if (viewPos.x > bufferZone && item.x - offset - this.padding_left > 0) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex - items.length;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.x = item.x - offset;
- }
- } else {
- //item左滑时,超出了scrollView左边界,将item移动到右方复用,item移动到右方的位置必须不超过content的右边界
- if (viewPos.x < -bufferZone && item.x + offset + this.padding_right < this.content.width) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex + items.length;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.x = item.x + offset;
- }
- }
- }
- this.lastContentPosX = this.scrollView.content.x;
- }
- /**网格垂直排列 */
- private updateGrid_V() {
- let items = this.itemList;
- let item: cc.Node;
- let bufferZone = this.halfScrollView;
- let isUp = this.scrollView.content.y > this.lastContentPosY;
- let offset = (this.itemHeight + this.spaceY) * (this.spawnCount / this.gridCol);
- for (let i = 0; i < items.length; i++) {
- item = items[i];
- let viewPos = this.getPositionInView(item);
- if (isUp) {
- //item上滑时,超出了scrollView上边界,将item移动到下方复用,item移动到下方的位置必须不超过content的下边界
- if (viewPos.y > bufferZone && item.y - offset - this.padding_buttom > -this.content.height) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex + (this.spawnCount / this.gridCol) * this.gridCol;
- if (this.itemDataList[itemIndex] != null) {
- item.y = item.y - offset;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.opacity = 255;
- } else {
- item.y = item.y - offset;
- itemRender.itemIndex = itemIndex;
- item.opacity = 0;
- }
- }
- } else {//item下滑时,超出了scrollView下边界,将item移动到上方复用,item移动到上方的位置必须不超过content的上边界
- if (viewPos.y < -bufferZone && item.y + offset + this.padding_top < 0) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex - (this.spawnCount / this.gridCol) * this.gridCol;
- if (this.itemDataList[itemIndex] != null) {
- item.y = item.y + offset;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.opacity = 255;
- } else {
- item.y = item.y + offset;
- itemRender.itemIndex = itemIndex;
- item.opacity = 0;
- }
- }
- }
- }
- this.lastContentPosY = this.scrollView.content.y;
- }
- /**网格水平排列 */
- private updateGrid_H() {
- let items = this.itemList;
- let item;
- let bufferZone = this.halfScrollView;
- let isRight = this.scrollView.content.x > this.lastContentPosX;
- let offset = (this.itemWidth + this.spaceX) * (this.spawnCount / this.gridRow);
- for (let i = 0; i < items.length; i++) {
- item = items[i];
- let viewPos = this.getPositionInView(item);
- if (isRight) {
- //item右滑时,超出了scrollView右边界,将item移动到左方复用,item移动到左方的位置必须不超过content的左边界
- if (viewPos.x > bufferZone && item.x - offset - this.padding_left > 0) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex - (this.spawnCount / this.gridRow) * this.gridRow;
- if (this.itemDataList[itemIndex] != null) {
- item.x = item.x - offset;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.opacity = 255;
- } else {
- item.x = item.x - offset;
- itemRender.itemIndex = itemIndex;
- item.opacity = 0;
- }
- }
- } else {
- //item左滑时,超出了scrollView左边界,将item移动到右方复用,item移动到右方的位置必须不超过content的右边界
- if (viewPos.x < -bufferZone && item.x + offset + this.padding_right < this.content.width) {
- let itemRender: ItemRender = item.getComponent(ItemRender);
- let itemIndex = itemRender.itemIndex + (this.spawnCount / this.gridRow) * this.gridRow;
- if (this.itemDataList[itemIndex] != null) {
- item.x = item.x + offset;
- itemRender.itemIndex = itemIndex;
- itemRender.data = this.itemDataList[itemIndex];
- itemRender.dataChanged();
- item.opacity = 255;
- } else {
- item.x = item.x + offset;
- itemRender.itemIndex = itemIndex;
- item.opacity = 0;
- }
- }
- }
- }
- this.lastContentPosX = this.scrollView.content.x;
- }
- /**获取item在scrollView的局部坐标 */
- private getPositionInView(item) {
- let worldPos = item.parent.convertToWorldSpaceAR(item.position);
- let viewPos = this.scrollView.node.convertToNodeSpaceAR(worldPos);
- return viewPos;
- }
- /**获取列表数据 */
- public getListData() {
- return this.itemDataList;
- }
- /**
- * 增加一项数据到列表的末尾
- * @param data 数据
- */
- public addItem(data: any) {
- this.itemDataList.push(data);
- this.updateContent();
- }
- /**
- * 增加一项数据到列表指定位置
- * @param index 位置,0表示第1项
- * @param data 数据
- */
- public addItemAt(index: number, data: any) {
- if (this.itemDataList[index] != null || this.itemDataList.length == index) {
- this.itemDataList.splice(index, 1, data);
- this.updateContent();
- }
- }
- /**
- * 删除一项数据
- * @param index 删除项的位置 ,0表示第1项
- */
- public deleteItem(index: number) {
- if (this.itemDataList[index] != null) {
- this.itemDataList.splice(index, 1);
- this.updateContent();
- }
- }
- /**
- * 改变一项数据
- * @param index 位置,0表示第1项
- * @param data 替换的数据
- */
- public changeItem(index: number, data: any) {
- if (this.itemDataList[index] != null) {
- this.itemDataList[index] = data;
- this.updateContent();
- }
- }
- /**获取第一个Item的位置 */
- private updateContent() {
- //显示列表实例为0个
- if (this.itemList.length == 0) {
- this.countListParam();
- this.createList(0, new cc.Vec2(0, 0));
- //显示列表的实例不为0个,则需要重新排列item实例数组
- } else {
- if (this.type == ListType.Vertical) {
- this.itemList.sort((a: any, b: any) => {
- return b.y - a.y;
- });
- } else if (this.type == ListType.Horizontal) {
- this.itemList.sort((a: any, b: any) => {
- return a.x - b.x;
- });
- } else if (this.type == ListType.Grid) {
- if (this.startAxis == StartAxisType.Vertical) {
- this.itemList.sort((a: any, b: any) => {
- return a.x - b.x;
- });
- this.itemList.sort((a: any, b: any) => {
- return b.y - a.y;
- });
- } else if (this.startAxis == StartAxisType.Horizontal) {
- this.itemList.sort((a: any, b: any) => {
- return b.y - a.y;
- });
- this.itemList.sort((a: any, b: any) => {
- return a.x - b.x;
- });
- }
- }
- this.countListParam();
- //获取第一个item实例需要显示的数据索引
- var startIndex = this.itemList[0].getComponent(ItemRender).itemIndex;
- if (this.type == ListType.Grid && this.startAxis == StartAxisType.Vertical) {
- startIndex += (startIndex + this.spawnCount) % this.gridCol;
- } else if (this.type == ListType.Grid && this.startAxis == StartAxisType.Horizontal) {
- startIndex += (startIndex + this.spawnCount) % this.gridRow;
- }
- //getScrollOffset()和scrollToOffset()的x值是相反的
- var offset: cc.Vec2 = this.scrollView.getScrollOffset();
- offset.x = - offset.x;
- this.createList(startIndex, offset);
- }
- }
- /**销毁 */
- public onDestroy() {
- //清理列表项
- let len = this.itemList.length;
- for (let i = 0; i < len; i++) {
- if (cc.isValid(this.itemList[i], true)) {
- this.itemList[i].destroy();
- }
- }
- this.itemList.length = 0;
- //清理对象池
- len = this.itemPool.length;
- for (let i = 0; i < len; i++) {
- if (cc.isValid(this.itemPool[i], true)) {
- this.itemPool[i].destroy();
- }
- }
- this.itemPool.length = 0;
- //清理列表数据
- this.itemDataList.length = 0;
- }
- }
以上就是如何在CocosCreator中做一个List的详细内容,更多关于CocosCreator List的资料请关注服务器之家其它相关文章!
原文链接:https://www.cnblogs.com/gamedaybyday/p/13270209.html