Question

Android上的BLE扫描不适用于Ionic4（4.12.0）简单测试应用程序。没有错误消息，启用检查又回来了。订阅永不返回。请参阅下面的logcat。任何帮助都非常感谢。

这是从头开始重现问题的方法：

ionic start BLEscanner blank
cd BLEscanner/
cordova plugin add cordova-plugin-ble-central --variable BLUETOOTH_USAGE_DESCRIPTION="Scan for mesh packets"
npm install --save @ionic-native/ble
ionic cordova platform add android@8.0.0 (tried with 7.1.0 and 6.4.0)
ionic cordova plugin add cordova-plugin-ionic-webview@latest

用以下代码替换home.page.ts：

import { OnInit, Component } from '@angular/core';
import { BLE } from '@ionic-native/ble/ngx';
import {
  Platform,
} from '@ionic/angular';

@Component({
  selector: 'app-home',
  templateUrl: 'home.page.html',
  styleUrls: ['home.page.scss'],
})
export class HomePage implements OnInit  {
  constructor(
    private ble: BLE,
    private platform: Platform,
  ){
    console.log("constructor home page");
  }

  async ngOnInit() {
    // Since ngOnInit() is executed before `deviceready` event,
    // you have to wait the event.
    await this.platform.ready();
    console.log(`enter view, start scanning`)
    this.ble.scan([], 5).subscribe(
      device =>
        console.log(JSON.stringify(device))),
      error => console.log(`error ${error}`);
  }
}

编译并运行：

ionic cordova run android --device

检查chrome：// inspect /＃devices进行检查并查看控制台。您得到的是：

Angular is running in the development mode. Call enableProdMode() to enable the production mode.
cordova.js:1218 deviceready has not fired after 5 seconds.
vendor.js:74395 Ionic Native: deviceready event fired after 3303 ms
home-home-module.js:98 constructor home page
home-home-module.js:135 enter view, start scanning

没有扫描结果。是的，目前有很多BLE广告客户。是的，该应用具有位置权限。

android logcat中的错误消息是：

05-03 15:30:42.368 17937 20508 I Places : ?: PlacesBleScanner stop()
05-03 15:30:42.394 17937 17937 I BeaconBle: 'L' hardware scan: scan stopped, no clients
05-03 15:30:42.394 17937 17937 I BeaconBle: Scan canceled successfully.

知道发生了什么事。奇怪的事情，这以前工作。一些版本不匹配？

Answer 1

答案是：离子版本不匹配。如果@ ionic-native / core和@ ionic-native / ble不同，它将停止工作

这有效：

"@ionic-native/ble": "^5.5.1",
"@ionic-native/core": "^5.5.1",

在Android上使用Ionic4进行BLE扫描：不扫描

1 个答案: