鸿蒙开发者社区

导入三方库"dependencies":{"ohospulltorefresh":"^2.0.5"}PullToRefresh({data:this.list,数据源scroller:this.scroller,customList:()>{this.getListView()List列表组件封装},onRefresh:()>{this.page1returnnewPromise((solve,reject)>{if(this.list){this.list[]}this.getData(()>{solve("")})})},onLoadMore:()>{returnnewPromise((solve,reject)>{this.getData(()>{solve("")})})}}).layoutWeight(1)

Provide('NavPathStack')pageInfos:NavPathStacknewNavPathStack();letparam:Record<string,Object>{};param['bigImageData']newStudent()this.pageInfos.pushPath({name:'secondPage',param:param},false);

WaterFlow配合LazyForeach实现高性能瀑布流build(){Column({space:2}){WaterFlow(){LazyForEach(this.datasource,(item:number)>{FlowItem(){Column(){Text("N"+item).fontSize(12).height('16')Image('reswaterFlowTest('+item%5+').jpg').objectFit(ImageFit.Fill).width('100%').layoutWeight(1)}}.width('100%').height(this.itemHeightArray[item]).backgroundColor(this.colors[item%5])},(item:string)>item)}.columnsTemplate("1fr1fr").columnsGap(10).rowsGap(5).backgroundColor(0xFAEEE0).width('100%').height('80%')}}

ObservedclassDateClassextendsDate{constructor(args:numberstring){super(args)}}ObservedclassNewDate{publicdata:DateClass;constructor(data:DateClass){this.datadata;}}ComponentstructChild{label:string'date';ObjectLinkdata:DateClass;build(){Column(){Button(childincreasethedayby1).onClick(()>{this.data.setDate(this.data.getDate()+1);})DatePicker({start:newDate('197011'),end:newDate('210011'),selecte...

应用进程创建&初始化阶段：该阶段主要是系统完成应用进程的创建以及初始化的过程，包含了启动页图标(startWindowIcon)的解码。Application&Ability初始化：该阶段主要是资源加载、虚拟机创建、Application&Ability相关对象的创建与初始化、依赖模块的加载等。AbilityAbilityStage生命周期：该阶段主要是AbilityStageAbility的启动生命周期，执行相应的生命周期回调。加载绘制首页：该阶段主要是加载首页内容、测量布局、刷新组...

设置TextInput的.defaultFocus为true.defaultFocus(true)

leturis:Array<string>[];constphotoViewPickernewphotoAccessHelper.PhotoViewPicker();photoViewPicker.select(photoSelectOptions).then((photoSelectResult:photoAccessHelper.PhotoSelectResult)>{urisphotoSelectResult.photoUris;console.info('photoViewPicker.selecttofilesucceedandurisare:'+uris);}).catch((err:BusinessError)>{console.error(InvokephotoViewPicker.selectfailed,codeis${err.code},messageis${err.message});})​​https:developer.huawei.comconsumercndocharmonyosguidesV5photoaccesshelperphotoviewpickerV5​​

import{audio}from'kit.AudioKit';letaudioStreamInfo:audio.AudioStreamInfo{samplingRate:audio.AudioSamplingRate.SAMPLERATE48000,采样率channels:audio.AudioChannel.CHANNEL2,通道sampleFormat:audio.AudioSampleFormat.SAMPLEFORMATS16LE,采样格式encodingType:audio.AudioEncodingType.ENCODINGTYPERAW编码格式};letaudioCapturerInfo:audio.AudioCapturerInfo{source:audio.SourceType.SOURCETYPEMIC,capturerFlags:0}...

.onItemDragStart((event:ItemDragInfo,itemIndex:number)>{第一次拖拽此事件绑定的组件时，触发回调。returnthis.pixelMapBuilder(this.data[itemIndex]);设置拖拽过程中显示的图片。}).onItemDrop((event:ItemDragInfo,itemIndex:number,insertIndex:number,isSuccess:boolean)>{if(!isSuccessinsertIndex>this.data.length){return}this.changeIndex(itemIndex,insertIndex)})​​https:ost.51cto.composts31032​​

在自定义组件时，加上export关键字，其他文件即可引用当前组件。ComponentexportstrutMyComponent{build(){}}

在aboutToApper中注册字体font.registerFont({familyName:"SourceHanSerifCNRegular",familySrc:"fontSourceHanSerifCN.otf"})在组件绑定字体Text(collection.name).width(20).fontSize(18).lineHeight(25).fontFamily("SourceHanSerifCNRegular")

PlayMode推荐使用PlayMode.Normal和PlayMode.Alternate，此场景下动画的第一轮是正向播放的。如使用PlayMode.Reverse和PlayMode.AlternateReverse，则动画的第一轮是逆向播放的，在动画刚开始时会跳变到终止状态，然后逆向播放动画。使用PlayMode.Alternate或PlayMode.AlternateReverse时，开发者应保证动画最终状态和状态变量的取值一致，即应保证动画的最后一轮是正向播放的。使用PlayMode.Alternate时，iterations应为奇数。...

componentSnapshot.get(NODECONTAINERID,async(error:Error,pixelMap:image.PixelMap)>{if(pixelMap!null){图片写入文件this.filePathawaitthis.saveFile(getContext(),pixelMap);logger.info(TAG,Imagessavedusingthepackingmethodarelocatedin:${this.filePath});}})

通过bindContentCover全屏模态转场实现对搜索页面显示的控制Column(){Column(){Search({placeholder:$r('app.string.searchplaceholder')}).focusOnTouch(false).focusable(false).enableKeyboardOnFocus(false).backgroundColor('E7E9E8').width(this.searchWidth).height(40).borderRadius($r('app.string.mainpagetopborderRadius')).onClick(()>{this.onSearchClicked()}).geometryTransition(this.geometryId,{follow:true...

将swiper区域分割为两块区域，上方为内容区域，下方为空白区域Column(){Image(item).width($r('app.string.onehundredpercent')).height($r('app.string.thirtypercent')).borderRadius($r('app.integer.borderRadiusvalue'))Column().width($r('app.string.onehundredpercent')).height($r('app.integer.blankspaceheight'))}通过indicator属性调整指示器导航点位置，使其位于空白区域Swiper(this.swiperController){...}.width($r('app.string.ninetyfivepercent')).loop(true).autoPlay(true).indicator(newDotIndicator().bottom($r('app.integer.offsetvalue')))

WaterFlow(){LazyForEach(this.dataSource,(item:string)>{FlowItem(){Column(){Text("N"+item).fontSize(12).height('16')存在对应的jpg文件才会显示图片Image（item).objectFit(ImageFit.Fill).width('100%').layoutWeight(1)}}.onAppear(()>{即将触底时提前增加数据if(item+20this.dataSource.totalCount()){for(leti0;i<100;i++){this.dataSource.addLastItem()}}}).width('100%').height(this.itemHeightArray[item%100])....

BasicDataSource代码见文档末尾附件:string类型数组的BasicDataSource代码classMyDataSourceextendsBasicDataSource{privatedataArray:string[][];publictotalCount():number{returnthis.dataArray.length;}publicgetData(index:number):string{returnthis.dataArray[index];}publicaddData(index:number,data:string):void{this.dataArray.splice(index,0,data);this.notifyDataAdd(index);}publicpushData(data:string):void{...

constcontextgetContext(this);获取resourceManager资源管理器constresourceMgr:resourceManager.ResourceManagercontext.resourceManager;constfileData:Uint8ArrayawaitresourceMgr.getMediaContent(this.imgData[targetIndex]);获取图片的ArrayBufferconstbufferfileData.buffer;创建imageSourceconstimageSource:image.ImageSourceimage.createImageSource(buffer);创建pixelMapconstpixelMap:image.PixelMapawaitimageSource.createPixelMap();effectKit.createColorPicker(pixelMap,(err,colorPicker)>{读取图像主色的颜色值，结果写入ColorletcolorcolorPicker.getMainColorSync();})

Button($r('app.string.fullscreenmodallogindescription')).fontColor(Color.White).borderRadius($r('app.integer.borderradius')).type(ButtonType.Normal).backgroundColor($r('app.color.grey2')).width($r('app.string.sizefull')).bindContentCover(this.isPresent,this.loginBuilder).onClick(()>{this.isPresenttrue;})

PixelMap深拷贝方法。通过readPixelsToBuffer读取图片资源的PixelMap到ArrayBuffer，再通过createPixelMap得到目标PixelMap。asyncfunctioncopyPixelMap(pm:PixelMap):Promise<PixelMap>{constimageInfo:image.ImageInfoawaitpm.getImageInfo();constbuffer:ArrayBuffernewArrayBuffer(pm.getPixelBytesNumber());TODO知识点：通过readPixelsToBuffer实现PixelMap的深拷贝，其中readPixelsToBuffer输出为BGRA8888awaitpm.readPi...