Question

I have a form and I want to display a confirmation dialogBox when the user presses the back button. Let say that I have one Texbonx that listens to a ChangeValueHandler

addValueChangeHandler(new ValueChangeHandler<String>() {    
    @Override
    public void onValueChange(ValueChangeEvent<String> event) {
        setChanged(true);
    }
}); 

This is the short scenario

1) I enter text in the TextBox

2) I hit the back button

3) The ValueChangeEvent is not called

I tried the fire the BlurEvent programmatically on the TextBox with textBox.fireEvent(new BlurEvent() { }); but still no result.

Any suggestions ?

Answer 1

What I did is to set the focus of the TextBox to False and then check if it’s changed, that forces the TextBox to unfocus when hiting the back button.

This is the code that check if a form is changed

public boolean isChanged(){
    if(formPanel == null) return false;     
    for (int i = 0; i < formPanel.getWidgetCount(); i++) {
        if(formPanel.getWidget(i) instanceof BaseWidget){
            BaseWidget w= (BaseWidget) formPanel.getWidget(i);
            w.setFocus(false);
            if(w.isChanged()){
                return true;
            }
        }
    }
    return false;
}