HarmonyOS 指纹登录如何实现

参考示例：

1.指纹识别依赖系统的指纹设置，先在手机系统中设置指纹。

2.module.json5文件中增加权限：

ohos.permission.ACCESS_BIOMETRIC
"requestPermissions": [
{
  name: "ohos.permission.ACCESS_BIOMETRIC"
}
]

3.实现认证逻辑：

AuthParam 配置授权参数。

getUserAuthInstance 获取AuthInstance对象，用于执行用户认证。

AuthInstance.start 开始认证。

核心代码：

import userAuth from '@ohos.userIAM.userAuth';
@Entry
@Component
struct Index {
  @State init: boolean = true;
  private challenge: Uint8Array = new Uint8Array([49, 49, 49, 49, 49, 49]);
  private authType: userAuth.UserAuthType = userAuth.UserAuthType.FINGERPRINT;
  private authTrustLevel: userAuth.AuthTrustLevel = userAuth.AuthTrustLevel.ATL1;
  private authInstance: userAuth.UserAuthInstance | undefined = undefined;

  createInstance() {
    this.authInstance = undefined;
    const authParam: userAuth.AuthParam = {
      challenge: this.challenge,
      authType: [this.authType],
      authTrustLevel: this.authTrustLevel,
    }
    const widgetParam :userAuth.WidgetParam = {
      title: '请输入密码',
    };
    // AuthInstance对象，用于执行用户认证
    this.authInstance = userAuth.getUserAuthInstance(authParam, widgetParam);
    this.authInstance.on('result', {
      onResult(result){
        console.log('userAuth 验证成功: ' + JSON.stringify(result))
      }
    });
    // 开始认证
    this.authInstance.start();
  }

  build() {
    Row() {
      Column() {
        Button('指纹识别')
          .width(200)
          .height(50)
          .fontSize(20)
          .onClick(()=>{
            this.createInstance()
          })
      }
      .width('100%')
    }
    .height('100%')
  }