// 示例：正确处理API请求
import { HttpClient } from '@angular/common/http';
import { catchError } from 'rxjs/operators';
import { throwError } from 'rxjs';

constructor(private http: HttpClient) {}

fetchData() {
  this.http.get('https://api.example.com/data')
    .pipe(
      catchError(error => {
        console.error('API请求失败:', error);
        // 显示错误信息或备用数据
        return throwError(error);
      })
    )
    .subscribe(data => {
      console.log('获取的数据:', data);
      this.data = data;
    });
}

<!-- 确保数据绑定正确 -->
<ion-list *ngIf="data && data.length">
  <ion-item *ngFor="let item of data">
    {{ item.name }}
  </ion-item>
</ion-list>

// 后端需要设置正确的CORS头
// 或者在开发环境中配置代理
// ionic.config.json
{
  "proxies": [
    {
      "path": "/api",
      "proxyUrl": "https://api.example.com"
    }
  ]
}

// 使用LoadingController处理加载状态
import { LoadingController } from '@ionic/angular';

async fetchData() {
  const loading = await this.loadingController.create({
    message: '加载中...'
  });
  await loading.present();

  this.http.get('https://api.example.com/data').subscribe(
    data => {
      this.data = data;
      loading.dismiss();
    },
    error => {
      console.error(error);
      loading.dismiss();
    }
  );
}

// 确保在正确的生命周期钩子中获取数据
import { Component, OnInit } from '@angular/core';

export class MyPage implements OnInit {
  ngOnInit() {
    this.fetchData();
  }
}