ext combobox listeners监听事件

可以看API上面的帮助文档：直接找combobox的events

autosize : ( Ext.form.Field this, Number width )
Fires when the autosize function is triggered. The field may or may not have actually changed size according to the ...
Fires when the autosize function is triggered. The field may or may not have actually changed size according to the default logic, but this event provides a hook for the developer to apply additional logic at runtime to resize the field if needed.
Listeners will be called with the following arguments:

* this : Ext.form.Field
This text field
* width : Number
The new field width

TextField
beforedestroy : ( Ext.Component this )
Fires before the component is destroyed. Return false to stop the destroy.
Fires before the component is destroyed. Return false to stop the destroy.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
beforehide : ( Ext.Component this )
Fires before the component is hidden. Return false to stop the hide.
Fires before the component is hidden. Return false to stop the hide.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
beforequery : ( Object queryEvent )
Fires before all queries are processed. Return false to cancel the query or set the queryEvent's cancel property to t...
Fires before all queries are processed. Return false to cancel the query or set the queryEvent's cancel property to true.
Listeners will be called with the following arguments:

* queryEvent : Object
An object that has these properties:
o combo : Ext.form.ComboBox
This combo box
o query : String
The query
o forceAll : Boolean
True to force "all" query
o cancel : Boolean
Set to true to cancel the query

ComboBox
beforerender : ( Ext.Component this )
Fires before the component is rendered. Return false to stop the render.
Fires before the component is rendered. Return false to stop the render.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
beforeselect : ( Ext.form.ComboBox combo, Ext.data.Record record, Number index )
Fires before a list item is selected. Return false to cancel the selection.
Fires before a list item is selected. Return false to cancel the selection.
Listeners will be called with the following arguments:

* combo : Ext.form.ComboBox
This combo box
* record : Ext.data.Record
The data record returned from the underlying store
* index : Number
The index of the selected item in the dropdown list

ComboBox
beforeshow : ( Ext.Component this )
Fires before the component is shown. Return false to stop the show.
Fires before the component is shown. Return false to stop the show.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
beforestaterestore : ( Ext.Component this, Object state )
Fires before the state of the component is restored. Return false to stop the restore.
Fires before the state of the component is restored. Return false to stop the restore.
Listeners will be called with the following arguments:

* this : Ext.Component
* state : Object
The hash of state values

Component
beforestatesave : ( Ext.Component this, Object state )
Fires before the state of the component is saved to the configured state provider. Return false to stop the save.
Fires before the state of the component is saved to the configured state provider. Return false to stop the save.
Listeners will be called with the following arguments:

* this : Ext.Component
* state : Object
The hash of state values

Component
blur : ( Ext.form.Field this )
Fires when this field loses input focus.
Fires when this field loses input focus.
Listeners will be called with the following arguments:

* this : Ext.form.Field

Field
change : ( Ext.form.Field this, Mixed newValue, Mixed oldValue )
Fires just before the field blurs if the field value has changed.
Fires just before the field blurs if the field value has changed.
Listeners will be called with the following arguments:

* this : Ext.form.Field
* newValue : Mixed
The new value
* oldValue : Mixed
The original value

Field
collapse : ( Ext.form.ComboBox combo )
Fires when the dropdown list is collapsed
Fires when the dropdown list is collapsed
Listeners will be called with the following arguments:

* combo : Ext.form.ComboBox
This combo box

ComboBox
destroy : ( Ext.Component this )
Fires after the component is destroyed.
Fires after the component is destroyed.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
disable : ( Ext.Component this )
Fires after the component is disabled.
Fires after the component is disabled.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
enable : ( Ext.Component this )
Fires after the component is enabled.
Fires after the component is enabled.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
expand : ( Ext.form.ComboBox combo )
Fires when the dropdown list is expanded
Fires when the dropdown list is expanded
Listeners will be called with the following arguments:

* combo : Ext.form.ComboBox
This combo box

ComboBox
focus : ( Ext.form.Field this )
Fires when this field receives input focus.
Fires when this field receives input focus.
Listeners will be called with the following arguments:

* this : Ext.form.Field

Field
hide : ( Ext.Component this )
Fires after the component is hidden.
Fires after the component is hidden.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
invalid : ( Ext.form.Field this, String msg )
Fires after the field has been marked as invalid.
Fires after the field has been marked as invalid.
Listeners will be called with the following arguments:

* this : Ext.form.Field
* msg : String
The validation message

Field
keydown : ( Ext.form.TextField this, Ext.EventObject e )
Keydown input field event. This event only fires if enableKeyEvents is set to true.
Keydown input field event. This event only fires if enableKeyEvents is set to true.
Listeners will be called with the following arguments:

* this : Ext.form.TextField
This text field
* e : Ext.EventObject

TextField
keypress : ( Ext.form.TextField this, Ext.EventObject e )
Keypress input field event. This event only fires if enableKeyEvents is set to true.
Keypress input field event. This event only fires if enableKeyEvents is set to true.
Listeners will be called with the following arguments:

* this : Ext.form.TextField
This text field
* e : Ext.EventObject

TextField
keyup : ( Ext.form.TextField this, Ext.EventObject e )
Keyup input field event. This event only fires if enableKeyEvents is set to true.
Keyup input field event. This event only fires if enableKeyEvents is set to true.
Listeners will be called with the following arguments:

* this : Ext.form.TextField
This text field
* e : Ext.EventObject

TextField
move : ( Ext.Component this, Number x, Number y )
Fires after the component is moved.
Fires after the component is moved.
Listeners will be called with the following arguments:

* this : Ext.Component
* x : Number
The new x position
* y : Number
The new y position

BoxComponent
render : ( Ext.Component this )
Fires after the component is rendered.
Fires after the component is rendered.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
resize : ( Ext.Component this, Number adjWidth, Number adjHeight, Number rawWidth, Number rawHeight )
Fires after the component is resized.
Fires after the component is resized.
Listeners will be called with the following arguments:

* this : Ext.Component
* adjWidth : Number
The box-adjusted width that was set
* adjHeight : Number
The box-adjusted height that was set
* rawWidth : Number
The width that was originally specified
* rawHeight : Number
The height that was originally specified

BoxComponent
select : ( Ext.form.ComboBox combo, Ext.data.Record record, Number index )
Fires when a list item is selected
Fires when a list item is selected
Listeners will be called with the following arguments:

* combo : Ext.form.ComboBox
This combo box
* record : Ext.data.Record
The data record returned from the underlying store
* index : Number
The index of the selected item in the dropdown list

ComboBox
show : ( Ext.Component this )
Fires after the component is shown.
Fires after the component is shown.
Listeners will be called with the following arguments:

* this : Ext.Component

Component
specialkey : ( Ext.form.Field this, Ext.EventObject e )
Fires when any key related to navigation (arrows, tab, enter, esc, etc.) is pressed. You can check Ext.EventObject.g...
Fires when any key related to navigation (arrows, tab, enter, esc, etc.) is pressed. You can check Ext.EventObject.getKey to determine which key was pressed.
Listeners will be called with the following arguments:

* this : Ext.form.Field
* e : Ext.EventObject
The event object

Field
staterestore : ( Ext.Component this, Object state )
Fires after the state of the component is restored.
Fires after the state of the component is restored.
Listeners will be called with the following arguments:

* this : Ext.Component
* state : Object
The hash of state values

Component
statesave : ( Ext.Component this, Object state )
Fires after the state of the component is saved to the configured state provider.
Fires after the state of the component is saved to the configured state provider.
Listeners will be called with the following arguments:

* this : Ext.Component
* state : Object
The hash of state values

Component
valid : ( Ext.form.Field this )
Fires after the field has been validated with no errors.

包含的事件很多啊，比如expand、beforeselect、select、keydown....自己去看一下API就清楚啦