本文實例講述了微信小程序實現頁面下拉刷新和上拉加載功能。分享給大家供大家參考，具體如下：
web手機端或App中經常會有下拉刷新，上拉加載這些功能。
微信小程序中如何實現下拉刷新，上拉加載的功能。
實現思路：
1.監聽界面的下拉刷新事件和上拉加載事件
2.下拉刷新時清空數據列表，并重新請求數據進行界面展示。
3.上拉加載增量請求數據，增量增加數據列表，增量界面展示
效果圖：
實現代碼：
WaterFall.wxml:
<!--pages/WaterFall/WaterFall.wxml--><view style="display:none"> <image wx:for="{{images}}" wx:key="id" id="{{item.id}}" src="{{item.pic}}" bindload="onImageLoad"></image></view><scroll-view scroll-y="true" style="height:{{scrollH}}px" bindscrolltolower="loadImages" bindscrolltoupper="PullDownRefresh"> <view style="width:100%"> <view class="img_item"> <view wx:for="{{col1}}" wx:key="id"> <image src="{{item.pic}}" style="width:100%;height:{{item.height}}px"></image> </view> </view> <view class="img_item"> <view wx:for="{{col2}}" wx:key="id"> <image src="{{item.pic}}" style="width:100%;height:{{item.height}}px"></image> </view> </view> </view></scroll-view>WaterFall.js：
let col1H = 0;let col2H = 0;Page({ data: { scrollH: 0, imgWidth: 0, loadingCount: 0, images: [], col1: [], col2: [] }, onLoad: function () { wx.getSystemInfo({ success: (res) => { let ww = res.windowWidth; let wh = res.windowHeight; let imgWidth = ww * 0.48; let scrollH = wh; this.setData({ scrollH: scrollH, imgWidth: imgWidth }); //加載首組圖片 this.loadImages(); } }) }, PullDownRefresh:function(){ console.log("頁面下拉2"); }, onShow: function () { console.log("頁面顯示"); }, /** * 生命周期函數--監聽頁面隱藏 */ onHide: function () { console.log("頁面隱藏"); }, /** * 用戶點擊右上角分享 */ onShareAppMessage: function () { console.log("點擊分享"); }, onImageLoad: function (e) { let imageId = e.currentTarget.id; let oImgW = e.detail.width; //圖片原始寬度 let oImgH = e.detail.height; //圖片原始高度 let imgWidth = this.data.imgWidth; //圖片設置的寬度 let scale = imgWidth / oImgW; //比例計算 let imgHeight = oImgH * scale; //自適應高度 let images = this.data.images; let imageObj = null; for (let i = 0; i < images.length; i++) { let img = images[i]; if (img.id === imageId) { imageObj = img; break; } } imageObj.height = imgHeight; let loadingCount = this.data.loadingCount - 1; let col1 = this.data.col1; let col2 = this.data.col2; //判斷當前圖片添加到左列還是右列 if (col1H <= col2H) { col1H += imgHeight; col1.push(imageObj); } else { col2H += imgHeight; col2.push(imageObj); } let data = { loadingCount: loadingCount, col1: col1, col2: col2 }; //當前這組圖片已加載完畢，則清空圖片臨時加載區域的內容 if (!loadingCount) { data.images = []; } this.setData(data); }, loadImages: function () { let images = [ { pic: "../../images/1.png", height: 0 }, { pic: "../../images/2.png", height: 0 }, { pic: "../../images/3.png", height: 0 }, { pic: "../../images/4.png", height: 0 }, { pic: "../../images/5.png", height: 0 }, { pic: "../../images/6.png", height: 0 }, { pic: "../../images/7.png", height: 0 }, { pic: "../../images/8.png", height: 0 }, { pic: "../../images/9.png", height: 0 }, { pic: "../../images/10.png", height: 0 }, { pic: "../../images/11.png", height: 0 }, { pic: "../../images/12.png", height: 0 }, { pic: "../../images/13.png", height: 0 }, { pic: "../../images/14.png", height: 0 } ]; console.log("dasddasd" + images); let baseId = "img-" + (+new Date()); for (let i = 0; i < images.length; i++) { images[i].id = baseId + "-" + i; } this.setData({ loadingCount: images.length, images: images }); }})希望本文所述對大家微信小程序設計有所幫助。
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