help in ${....} value binding

[孟凡振]

I am using t5 plus extjs(a javascript framwork)
some code fragment in *.tml
..
items: [{
                    fieldLabel: 'name',
                    name:'formValue',
                    value:'${formValue}'
                }],

.............
and some in page class
.......
   private String _formValue;

    public String getFormValue(){
        return _formValue;
    }
    public void setFormValue(String formValue){
        this._formValue = formValue;
    }
......
Now, my problem is that I can get value by ${formValue}.
but when I change change the textField  I  can't get  the  changed value
in  page  class.....
so ,anyone  with  warmheart  can  help  me  here  for  binding  value?????
thanks  in  advance..