Problems on android

ThomasCoopman — Sun, 12 Dec 2021 00:13:34 GMT

I have a problem with the ArcGIS Javascript API on android. (it could be linked with the problem I described in a previous post (see here) but I don't believe this is the case, however I'm not sure so I'm linking the issue)

The problem occurs on android 4.2.2 with the Chrome browser.

After some navigation interaction (pinching, swiping, dragging,...) with the map I sometimes get the following error: Uncaught TypeError: Cannot read property 'identifier' of undefined

It's rather hard to debug the minified javascript code so I formatted it (http://jsbeautifier.org/) and ran it through a debugger to find out what the problem was.

In the function _touchMove:

 if (this._numTouches === 2) {
    var _ba1 = this._nodeTouches[0],
         _ba2 = this._nodeTouches[1];
    if (!this._pinchActive) {
       if (_b9f) {
          var _ba3 = _b9d[_ba1.identifier],
               _ba4 = _b9d[_ba2.identifier],
 ....

The error is on the line _ba4 = _b9d[_ba2.identifier]. Uncaught TypeError: Cannot read property 'identifier' of undefined and undifend is _ba2. The problem is that this._numTouches === 2 but _this._nodeTouches.length === 1

After debugging some more I found out that the problem must be with the _addTouch and _removeTouch method. I believe that _removeTouch is not always called but It's hard to confirm this. I've detected this by logging _this.numTouches. The behaviour I got was that touching with multiple fingers (more then 3 for example) and then lifting them again, _this.numTouches didn't always go down to 0.

As a fix for my own, I did this:

_addTouch: function (_bc4) {
  var i, _bc5 = _bc4.changedTouches,
         _bc6 = this._nodeTouches;
  this._numTouches = _bc4.touches.length;
  //this._numTouches += _bc5.length;
  ...
}

So instead of using _bc4.changedTouches.length I use _bc4.touches.length (likewise in _removeTouch). Are there any reasons changedTouches is used instead of touches?

Some follow up questions:

Is there any chance you will post your de-uglified API online? Maybe even make the API available on github?

Is this forum the right place to ask these kind of questions? This looks like a bug to me.

Re: Problems on android

JeffJacobson — Tue, 30 Apr 2013 15:23:56 GMT

Is this forum the right place to ask these kind of questions? This looks like a bug to me.

Yes, this would seem to be the right place to ask.

If you have a support contract with Esri you can file a bug report at http://support.esri.com. As far as I know that is the only way to file a bug report, but the JS API devs do read this forum.

Re: Problems on android

ThomasCoopman — Thu, 02 May 2013 06:08:01 GMT

If you have a support contract with Esri you can file a bug report at http://support.esri.com. As far as I know that is the only way to file a bug report, but the JS API devs do read this forum.

Ok, thanks. I'll wait for a dev to come around then.

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Problems on android

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