HarmonyOS 鸿蒙Next 全局自定义弹窗怎么写

嗯，您可以使用PromptAction，参考链接：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-promptaction-V5#promptactionshowtoast

import { promptAction } from '@kit.ArkUI'
import { BusinessError } from '@kit.BasicServicesKit';

@Entry
@Component
struct LoginPage {
  @State message: string = 'Hello World';
  @State num: number = 0

  build() {
    Column() {
      Column() {
        Button('showToast').onClick(() => {
          if (this.num === 0) {
            try {
              promptAction.showToast({
                message: '当前账号被其他设备登录，请重新登录',
                duration: 2000,
                showMode: promptAction.ToastShowMode.TOP_MOST
              });
            } catch (error) {
              let message = (error as BusinessError).message
              let code = (error as BusinessError).code
              console.error(`showToast args error code is== ${code}, message is ${message}`);
            }
            ;
          } else {
            try {
              promptAction.showToast({
                message: '登录成功',
                duration: 2000,
                showMode: promptAction.ToastShowMode.TOP_MOST
              });
            } catch (error) {
              let message = (error as BusinessError).message
              let code = (error as BusinessError).code
              console.error(`showToast args error code is== ${code}, message is ${message}`);
            }
            ;
          }

        })
      }
    }
    .backgroundColor("#F1F3F5")
    .justifyContent(FlexAlign.Center)
    .width('100%')
    .height('100%')
  }
}