instance of Array + GWT + Buttons + IFRAME = BUG in Panel.js

[grigoryevigor]

I'm using wrapper with OL API in GWT application. I found problem with Array type detection in OL. It just not works for array passed from other frame (see:  http://javascript.crockford.com/remedial.html).

As for me the problem resides in Panel.js addControls function

/*-------------------------------------------------------------*/

addControls: function(controls) {

if (!(controls instanceof Array)) {

controls = [controls];

} this.controls = this.controls.concat(controls);

/*-------------------------------------------------------------*/

failing to detect type correctly, it wraps array once more to the effect of nonsense. I also found 40 places using similar sintax around a project code. I'm suggesting to replace instanceof with a typeOf function usage from example (see URL above).

[grigoryevigor]

Forgot to mention that GWT injects it's scripts in IFRAME, so that effect, described in article, of failing instanceof operation takes effect, when I'm trying to add controls array, created with GWT to Panel.

I'm loading OL from a host page.

[erilem]

See  http://perfectionkills.com/instanceof-considered-harmful-or-how-to-write-a-robust-isarray/

[grigoryevigor]

Based on previous comment, I'm proposing to add this function to Util, and use it to detect arrays:

/**

• Function: typeOf
• This function extends typeof operator and fixes it's missbehavior
• with arrays and null. Accepts arrays from foreign frames and windows.
• @see  http://javascript.crockford.com/remedial.html
• @see  http://perfectionkills.com/instanceof-considered-harmful-or-how-to-write-a-robust-isarray/ */

OpenLayers.Util.typeOf = function (value) {

var s = typeof value; if (s === 'object') {

if (value) {

if (Object.prototype.toString.call(value) === '[object Array]') {

s = 'array';

}

} else {

s = 'null';

}

} return s;

};

[mwootendev]

Patch that adds OpenLayers.Util.isArray() and utilizes it for Array tests.

[mwootendev]

I have added a patch that should resolve the issue. The patch adds an OpenLayers.Util.isArray(a) function that utilizes the toString() method mentioned above. I though this might be cleaner than typeOf() === "array".

I replaced all "x instanceof Array" instances in the library code with "OpenLayers.Util.isArray(x)".

I added a test case for isArray() to Utils.html.

[tschaub]

Thanks for the solid patch. Tests pass in Chrome 12, Safari 5, Firefox 4, and IE 6.

[tschaub]

(In [12095]) More robust array type check. p=mwootendev, r=me (closes #2959)

[tschaub]

r12097 brings in an additional test.

[ahocevar]

in 2.11-rc2