Add property for ignoring touch dragging on the slider bar

[NovapaX]

Only a tap and a mousedown on the bar should alter the knob-position.
Fixes #178

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[NovapaX]

CLA signed

[googlebot]

CLAs look good, thanks!

[NovapaX]

This is a bit more complicated than initially thought.
To accomplish this in a clean way there should be a mousetrack event. So we could just reuse the onTrack function and set on-mousetrack="_onTrack" on the slider bar.
Or someone must have another idea how to accomplish the following behaviour:

• mouse click on the bar sets position and starts dragging
• touchmove on the bar does nothing
• touch tap on the bar sets position

[NovapaX]

oh wow... looks like I can't test the click event.
created a seperate PR for that: PolymerElements/iron-test-helpers#93

[e111077]

This is a breaking change. Can you please hide this feature under a flag? I'm guessing you can do this in connected callback:

properties = {
  __boundListenFn:  {
    type: Function
  },
  __eventType:  {
    type: string,
    value: 'down'
  },
  /**
   * insert closure doc
   */
  ignoreBarClicks: {
    type: Boolean,
    value: false
  }
}

connectedCallback() {
  ...
  if (this.ignoreBarClicks) {
    // or however you want to implement this
    this.__eventType = 'click';
    this.__boundListenFn = this._barclick.bind(this);
  } else {
    this.__eventType = 'down';
    this.__boundListenFn = this._bardown.bind(this);
  }

  this.$.slderBar.addEventListener(this.__eventType, this.__boundListenFn);
}

disconnectedCallback() {
  ...
  this.$.slderBar.removeEventListener(this.__eventType, this.__boundListenFn);
}

I'll see if i can figure out what's going on with mockInteractions

[NovapaX]

I came up with a working solution that ignores tracking of touches on the slider bar, but allows tapping on the slider bar to set the knob position.
Also was able to enable it all throught the on-[event] attributes so no need to manually set and tear down eventListeners.

[e111077]

Hmm, I think this will work. I have to run it through an internal suite of tests to see if it breaks anything; we may be able to push this through as a bug fix

[e111077]

This PR slipped through the cracks. Will prioritize internal testing

[e111077]

All tests pass. You're golden!

[NovapaX]

Great! Thanks for your help!

[NovapaX]

any idea on whether (and when) this can get pushed into a release?

[e111077]

We've been moving to a weekly release committee / schedule. Expect to see an update on Friday

[e111077]

Released a v2.0.5