Polymer 2.0中的factoryImplementation

Question

In Polymer 1.0 there was the possibility to detect if a polymer element was created by contructor, the function that was triggered when the element was created named factoryImpl().

I wan't to do the same in Polymer 2.0, if i create an element via a constructor, a standard function should be triggered and should do something. Does anyone done this before and can give a hint to do that?

Thanks a lot

Answer 1

You can use constructor:

class TestEle extends Polymer.Element {
      static get is() { return 'test-ele'; }
      constructor() {
        super()
        console.log('created')
      }
//...

You should see 'created' logged whenever you create TestEle

<test-ele> </test-ele> // created
or 
document.createElement('test-ele') // created
or
new TestEle() // created

// Edited as per the comments below.

I couldn't find any information on the legacy factoryImpl equivalent in 2.0. However, there's a work around you could try.

class TestEle extends Polymer.Element {
      static get is() { return 'test-ele'; }
      constructor(c) {
        super()
        console.log('created')
        if(c) {
           console.log('created using constructor')
        }
      }
...

<test-ele> </test-ele> // created
or 
document.createElement('test-ele') // created
or
new TestEle(true) // created and created using constructor