Fixed multiple call on language change.

[NayanKhedkar]

Refer:Issue

[danielstorey]

This will prevent the rendering of multiple progress bars, but I'm not sure it will take into account the new settings when the language is changed.

[moloko]

I had a thought that maybe we could get PageLevelProgressNavigationView to do this.remove on app:languageChange - but it doesn't quite seem to be doing the job. I haven't exactly spent a lot of time on it (and now have to do something else) but still feel it might be a valid solution?

stupid idea! never going to work...

[moloko]

OK, I think changing the initialize function adapt-contrib-pageLevelProgress.js to this:

Adapt.on({
    'app:dataReady': this.onDataReady.bind(this),
    'app:languageChanged': function() {
        this.stopListening();
    }.bind(this)
});

works OK...?

If, like me, you look at that code and are tempted to tidy it up, be aware that if you do either this:

Adapt.on({
    'app:dataReady': this.onDataReady,
    'app:languageChanged': this.stopListening
}, this);

Then both those event handlers get removed by this.stopListening as well.

This works:

Adapt.on({
    'app:dataReady': this.onDataReady.bind(this),
    'app:languageChanged': this.stopListening.bind(this)
});

[NayanKhedkar]

@moloko I am also wondering.
'app:languageChanged': this.stopListening.bind(this)

'app:languageChanged': function() { this.stopListening(); }.bind(this)

both these two line doing same thing.May be the mess with scope.

should I go with.
Adapt.on({
    'app:dataReady': this.onDataReady.bind(this),
    'app:languageChanged': function() {
        this.stopListening();
    }.bind(this)
}) ;

[moloko]

both these two line doing same thing

Well, you'd think so wouldn't you? but when I tried this.stopListening.bind(this) I'm pretty sure that it removed ALL the listeners! But then it was getting pretty late at that point so I may have made a simple mistake like forgetting to reload properly or doing so too quickly so the dev process hadn't finished... you know the sort of thing I'm sure ;-) So please feel free to give this a try for yourself and see what works and then I will re-test once you're happy.

[NayanKhedkar]

Adapt.on({
    'app:dataReady': this.onDataReady.bind(this),
    'app:languageChanged': function() {
        this.stopListening();
    }.bind(this)
});

Worked fine for me.