想了解更多关于开源的内容，请访问：
51CTO 开源基础软件社区
https://ost.51cto.com
介绍
本期笔者将分享一个基于ArkTS的HarmonyOS电量卡片开发案例，而案例实现的过程也是超级简单。
开发环境要求
● DevEco Studio版本：DevEco Studio 3.1 Release
● HarmonyOS SDK版本：API version 9
工程要求
● API9
● Stage模型
正文
实现逻辑
电量卡片的开发逻辑非常简单，首先要在工程已有的模块中新建一个ArkTS卡片；接着在卡片对应的EntryFormAbility类中编写一个获取电池信息的成员方法，并重写onAddForm方法（这个方法会在卡片被创建时执行），使得formData（携带了设备的电池信息）经处理后传递给卡片页面的本地数据库；最后，在卡片页面中声明一些变量，将它们与本地数据库绑定，同时在UI描述中将变量所携带的数据（与电池信息相关）通过组件渲染出来。
代码结构
main
├─ module.json5
├─ resources
│ ├─ zh_CN
│ ├─ rawfile
│ │ ├─ charging.png
│ │ └─ logo.png
│ ├─ en_US
│ └─ base
│ ├─ profile
│ │ ├─ form_config.json
│ │ └─ main_pages.json
│ ├─ media
│ └─ element
└─ ets
├─ widget
│ └─ pages
│ └─ WidgetCard.ets
├─ pages
│ └─ Index.ets
├─ entryformability
│ └─ EntryFormAbility.ts
└─ entryability
└─ EntryAbility.ts关键代码
form_config.json：
{
"forms": [
{
"name": "widget",
"description": "This is a service widget.",
"src": "./ets/widget/pages/WidgetCard.ets",
"uiSyntax": "arkts",
"window": {
"designWidth": 720,
"autoDesignWidth": true
},
"colorMode": "auto",
"isDefault": true,
"updateEnabled": true,
"scheduledUpdateTime": "07:30",
"updateDuration": 1,
"defaultDimension": "2*2",
"supportDimensions": [
"2*2"
]
}
]
}EntryFormAbility.ts：
import formInfo from '@ohos.app.form.formInfo';
import formBindingData from '@ohos.app.form.formBindingData';
import FormExtensionAbility from '@ohos.app.form.FormExtensionAbility';
import formProvider from '@ohos.app.form.formProvider';
//导入电池信息模块
import batteryInfo from '@ohos.batteryInfo';
export default class EntryFormAbility extends FormExtensionAbility {
onAddForm(want) {
//初始化卡片所携带的数据
let formData = this.getBatteryInfo()
return formBindingData.createFormBindingData(formData);
}
onCastToNormalForm(formId) {
}
onUpdateForm(formId) {
//更新卡片所携带的数据
let data = formBindingData.createFormBindingData(this.getBatteryInfo())
formProvider.updateForm(formId,data)
}
onChangeFormVisibility(newStatus) {
}
onFormEvent(formId, message) {
}
onRemoveForm(formId) {
}
onAcquireFormState(want) {
return formInfo.FormState.READY;
}
//新声明一个成员方法, 通过batteryInfo模块获取电池信息
private getBatteryInfo(){
return {
'BatterySOC':batteryInfo.batterySOC,
'BatteryTemperature':batteryInfo.batteryTemperature*0.1,
'ChargingStatus':batteryInfo.chargingStatus,
'BatteryHealthState':batteryInfo.BatteryHealthState
}
}
};Index.ets：
//实例化LocalStorage
var Store = new LocalStorage()
@Entry(Store)
@Component
struct WidgetCard {
/*
* The title.
*/
readonly TITLE: string = 'Hello World';
/*
* The action type.
*/
readonly ACTION_TYPE: string = 'router';
/*
* The ability name.
*/
readonly ABILITY_NAME: string = 'EntryAbility';
/*
* The message.
*/
readonly MESSAGE: string = 'add detail';
/*
* The with percentage setting.
*/
readonly FULL_WIDTH_PERCENT: string = '100%';
/*
* The height percentage setting.
*/
readonly FULL_HEIGHT_PERCENT: string = '100%';
//变量与本地数据库绑定
@LocalStorageProp('BatterySOC') BatterySOC: number = 30
@LocalStorageProp('BatteryTemperature') BatteryTemperature: number = 20
@LocalStorageProp('ChargingStatus') ChargingStatus: boolean = true
@LocalStorageProp('BatteryHealthState') BatteryHealthState: number = 1
//用Array储存批量数据
HealthState: Array = ['正常', '未知', '过热', '过压', '低温', '僵死']
build() {
Row() {
Column() {
//Stack组件,使得其子组件可以层叠布局
Stack() {
//Progress组件用于实现进度条
Progress({
total: 100,
value: this.BatterySOC,
type: ProgressType.Capsule
})
.width('89%')
.height(30)
.color(Color.Pink)
//电量文本和充电图标
Row() {
Text(this.BatterySOC + '%')
.fontSize(14)
.fontWeight(700)
if (this.ChargingStatus) {
Image($rawfile('charging.png'))
.height(20)
.width(10)
.margin({
left: 2
})
}
}
}.layoutWeight(2)
.width(this.FULL_WIDTH_PERCENT)
Row() {
//Image组件
Image($rawfile('logo.png'))
.height('60%')
.margin({
left: 6
})
.layoutWeight(2)
Column({
space: 7
}) {
Text('电池温度: ' + this.BatteryTemperature + '℃')
.fontSize(10)
.fontWeight(700)
.margin({
top: 19
})
Text('电池状态: ' + this.HealthState[this.BatteryHealthState])
.fontSize(10)
.fontWeight(700)
if (this.ChargingStatus) {
Text('正在充电')
.fontSize(10)
.fontWeight(700)
} else {
Text('正在耗电')
.fontSize(10)
.fontWeight(700)
}
}
.height(this.FULL_HEIGHT_PERCENT)
.layoutWeight(3)
}.layoutWeight(3)
.width(this.FULL_WIDTH_PERCENT)
}
.width(this.FULL_WIDTH_PERCENT)
}
.height(this.FULL_HEIGHT_PERCENT)
.onClick(() => {
postCardAction(this, {
"action": this.ACTION_TYPE,
"abilityName": this.ABILITY_NAME,
"params": {
"message": this.MESSAGE
}
});
})
}
}想了解更多关于开源的内容，请访问：
51CTO 开源基础软件社区
https://ost.51cto.com
