Spinner: Document that manually entered values are never modified - Fixe...

[jzaefferer]

...s #161

[tjvantoll]

"When the spinner is not read only"
"read only" as in the readonly HTML attribute?

"the user may enter a value via the text field that causes an invalid value"
This reads a little strange because "value" is included twice. Maybe something like "the user may enter an invalid value into the text field (below min, etc..." Just a suggestion.

[scottgonzalez]

We should probably include an example of how to force a valid value on blur, with a note about potential usability issues when doing so.

[jzaefferer]

Updated the wording, including a code example for the readonly attribute. I'm not sure right now how to force a valid value on blur.

[scottgonzalez]

The value() method handles parsing and validation, but only when it's able to actually parse a value. So, you can check if a value is parseable by calling elem.spinner( "value" ). If you get back null, the value couldn't be parsed. However, getting a value just means the value is parseable, not that it's valid (there could be a step-mismatch or an out of range error). Setting the value will parse and validate the value. So if you pass a parseable, but invalid value, then the value will be adjusted to be the nearest valid value. However, if you pass a value that cannot be parsed, the value will be set as is.

We should probably add some more detail to the value() description to explain this.

---

Note: I thought that value() adjusted the value in addition to just parsing. I don't recall details from any discussions about this, so I'm not sure if this was intentional or an oversight. Do people think we should change the behavior? There are no unit tests checking the result when starting from an invalid value (at least changing the implementation caused no test failures).

[tjvantoll]

So like http://jsfiddle.net/tj_vantoll/2bxRU, right?

I'm a bit torn. It would be nice to have a means of getting a valid value, but I would personally not expect value() to do this. I would expect to get what the <input> is displaying as a number (which is consistent with <input type="number">).

[scottgonzalez]

@tjvantoll I think you forgot to save your changes. The fiddle is just a standard spinner.

[tjvantoll]

Whoops. http://jsfiddle.net/tj_vantoll/AGPL6/

[scottgonzalez]

Ok, let's keep the current behavior.

[jzaefferer]

I still don't know what to add to address "how to force a valid value on blur".

[scottgonzalez]

var value = elem.spinner( "value" );
if ( value === null ) {
    elem.val( "" );
} else {
    elem.spinner( "value", value );
}

After discussing this in IRC, I think we actually shouldn't show how to do this, but instead just add an isValid() method: http://bugs.jqueryui.com/ticket/9542