ionic2.0消息訂閱監聽機制

兩種方案：一、session、watchCurrentCustomer().subscribe(data => {});訂閱機制；二、events機制.下面將以代碼重現

方案一：

import {Injectable} from '@angular/core';

import 'rxjs/Rx';

import {LocalStorage, Storage} from "ionic-angular/index";

import {Subject} from "rxjs/Subject";

import {Customer} from "../models/Customer";

import {BehaviorSubject} from "rxjs/BehaviorSubject";

import {Observable} from "rxjs/Observable";

@Injectable() export class XXXXXSession extends Observable<Customer>{ private local:Storage; private currentCustomer:Subject<Customer> = new BehaviorSubject<Customer>(null); private customer; private residence;

constructor(appConfig:AppConfig) {
    this.local = new Storage(LocalStorage);
    this.local.get('Customer').then(cust=> {
        console.info(cust);
        if (cust != null) {
            this.login = true;
            this.customer = JSON.parse(cust);
        }
    });
    this.local.get('Residence').then(residence=> {
        console.info(residence != null);
        if (residence != "") {
            this.residence = JSON.parse(residence);
        }
    });
}
isLogin() {
    return this.login;
}
getCustomer() {
    return this.customer;
}
setCustomer(customer) {
    this.currentCustomer.next(customer);
    this.local.set('Customer', JSON.stringify(customer));
    this.login = true;
}
 getCustomerId() {
    if (this.customer != null) {
        return this.customer.customerId;
    }
    return 1;
}
getResidence() {
    return this.residence;
}
getResidenceId() {
    if (this.residence != null) {
        return this.residence.residenceId;
    }
    return 1;
}
setResidence(residence) {
    this.local.set('Residence', JSON.stringify(residence));
    this.residence = residence;
}

}

監聽者： XXXXSession.watchCurrentCustomer().subscribe(data => {});

XXXXSession.watchCurrentCustomer().subscribe(data => {
            if(data == null){
                this.portrait = "img/not_login.png";
                this.isShop = false;
                this.customer = null;
                this.nickName = null;
            }else {

                this.customer = data.customer;
                this.nickName = this.customer.nickName;
                this.portrait = data.customer.portrait;
                this.queryCustomerShop(this.customer.customerId);
            }
        });
        XXXXSession.watchCurrentResidence().subscribe((newResidence) => {
            if(newResidence!=null){
                this.defaultResidence=newResidence.residenceName;
            }else{
            }
        });
        
    }

方案2、Events機制 import 'rxjs/Rx';

import {LocalStorage, Storage, Events} from "ionic-angular/index";

@Injectable() export class CustomerSession {

private static local:Storage = new Storage(LocalStorage);

private static customer;

private static residence;

constructor(public events:Events) {

}

initSession() {
    CustomerSession.local.get('Customer').then(cust=> {
        if (cust != null) {
            CustomerSession.customer = JSON.parse(cust);
            this.events.publish("Customer:changed", CustomerSession.customer);
        }
    });
    CustomerSession.local.get('Residence').then(residence=> {
        if (residence != null) {
            CustomerSession.residence = JSON.parse(residence);
            this.events.publish("Residence:changed", CustomerSession.residence);
        }
    });
}

}

其餘地方監聽： this.events.subscribe('Customer:changed', (eventData) => {

if (eventData != null && eventData.length > 0) {

            this.customer = eventData[0];

            this.nickName = this.customer.nickName;

            this.portrait = this.customer.portrait;

            this.queryCustomerShop(this.customer.customerId);
            
        }else{

            this.portrait = "img/not_login.png";

            this.isShop = false;

            this.customer = null;

            this.nickName = "XXXX";
        }
    });
    this.events.subscribe('Residence:changed', (eventData) => {

        if (eventData != null && eventData.length > 0) {

            this.defaultResidence=eventData[0].residenceName;
        }
    });