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// JavaScript debug toolbox


// Measure 
console.time()						// Starts a timer (can track how long an operation takes)
console.timeEnd()					// Stops a timer that was previously started by console.time()
console.count();
let start = performance.now(); 					// better accuracy 
let execTime = start - performance.now(); 		// than above 

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const random = () => { return Promise.resolve(Math.random()); }

// Callback hell
const sum randomAsyncAwait = () => {
  let first;
  let second;
  let third;
  
  return random.then(val => {
    first = val;

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imageObservables = {};

  getImageUrl(ref: string) {
    if (!ref) { return; }
    const regEx: RegExp = /^[0-9]/;
    if (!regEx.test(ref.charAt(0))) { return; }

    if (ref in this.imageObservables) {
      return this.imageObservables[ref];
    } else {

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Prerequisite

• Java, and set JAVA_HOME environment variable
• Gradle https://gradle.org/install/
• Android studio OR android sdk-build-tools

Run sudo find / -type d -name 'android' and find
*/Android/Sdk/*. We will export it to our PATH in our current shell. Follow https://stackoverflow.com/questions/23042638/how-do-i-set-android-sdk-home-environment-variable

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Deployment build Ionic Prototype

__ Update your version in config.xml__

Test in browser before

ionic cordova run browser --prod --release 

ionic cordova resources
ionic cordova build android --prod --release
## --prod compress apk && uses the 'prod' envrionment at build time, --release makes the app signable (so that it can be pusblished in marketplace)

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With Firebase you can choose between Realtime database & Cloudn Firestore depending on you pricing plan.
With the onSnapshot(..) function your client app will be updated imidiately after your server get updated, always realtime updates!
Other perks:

• Cloud functions
• Upgrade price plan as you grow
• Firebase is very likely to continue be maintained in the future.

Getting started with Firebase

npm install -g firebase-tools

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-support-google-services --save Full Instructions @ https://github.com/chemerisuk`ionic g guard guards/auth`

{ path: 'nav', canActivate: [AuthGuard], loadChildren: './navigation/navigation.module#NavigationPageModule' },

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Markdown Cheatsheet

Headers
# H1
## H2
### H3
#### H4
##### H5
###### H6

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In mySerivce.ts make sure it is providedIn 'root'

@injectable({
  provideIn: 'root'
)}
export class myService { ... }  

In app.module.ts add the service to Providers

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// Dictionary with Observable 
dictionary = {};

getItem(name) {
  if (name in this.dictionary) {
    return this.dictionary[name]
  } else {
    this.dictionary[name] = getObserverableByName(name)
    return this.dictionary[name]
  }