1. Explain extjs decode()?

var json = Ext.decode(response.responseText);
Ext.Msg.alert('Error', json.error);

2. Explain how to register callbacks to the load and exception events of the JsonStore?

var grid = new Ext.grid.GridPanel({
store: new Ext.data.JsonStore({
[...]
listeners: {
load: this.onLoadSuccess.crateDelegate(this),
exception: this.onLoadException.createDelegate(this)
}
}),

onLoadSuccess: function () {
// success
},

onLoadException: function () {
// error
},

[...]
}

4. Explain what are components required for grid panel?

store, columnmodel, id, width,height
46. how to disable menu option for header in columnModel?
using menuDisabled: true

5. Tell me how to apply css on select of combo box?

using config option as
emptyClass : 'emptycss', where emptycss is a css classname

6. Explain how to get a value of textfield or combo box?

using getvalue();
var selectedValue = mytextfield.getValue();

7. Tell me what is use of combo select event function?

To get the selected value from a combo.using getvalue();
var selectedComboValue = mycombo1.getValue();