Closure

[kleite]

It would appear to me that there might be a closure problem with calling routines with one of the parameters defined as:

scope: this

There are several routines that use the statement:

var me = this;

And then use 'me' for the scope. That looks like to me to be a proper method to handle closure. Routines like:

Ext.form.Panel, Ext.field.Select, Ext.TitleBar and many others might have a problem.

Try scanning the source code with 'scope: this' or just with ': this' (without the quotes) to review all the situations that might need a closure variable.

Thanks,
Kris

[mitchellsimoens]

Ext.form.Panel, Ext.field.Select, and Ext.TitleBar do not accept scope as a config. Can you be more specific with one example?

[kleite]

For Ext.form.Panel starting at line 217:

initialize: function() {
var me = this;
me.callParent();


me.on({
action: 'onFieldAction',
scope : me
});


me.element.on({
submit: 'onSubmit',
scope : this <--------------------------
});
},


For Ext.field.Select starting at line 128:

initialize: function() {
this.callParent();


this.getComponent().on({
scope: this, <-----------------------------------
masktap: 'onMaskTap'
});
},


For Ext.TitleBar.js starting at line 143:

this.sizeMonitors = {
leftBox: new SizeMonitor({
element: leftBox.renderElement,
callback: this.refreshTitlePosition,
scope: this <---------------------------------------
}),
spacer: new SizeMonitor({
element: spacer.renderElement,
callback: this.refreshTitlePosition,
scope: this <-----------------------------------------
}),
rightBox: new SizeMonitor({
element: rightBox.renderElement,
callback: this.refreshTitlePosition,
scope: this <----------------------------------------
})
};

[mitchellsimoens]

The reason for using

var me = this;

Is to save space when compiled, nothing more. In Ext.form.Panel, yeah, that does need to be changed. Ext.field.Select it wouldn't save any space as you have to overcome the characters 'var me = this;' introduces. In Ext.TitleBar, there is a great example of a chance to save a few bytes.