GWT材质-设置下拉选择文本

Question

It appears that a selected item in a GWT Material DropDown does not "stick" like a traditional DropDown.

First question, is that intended with new Material Designs? Am I doing something wrong? Is there something wrong with the library I am using?

Secondly, either way, I want the selected value to take the place of the default text. Is there a better way to do it than this?

UIBinder:

<m:MaterialContainer ui:field="materialContainer" paddingLeft="280">
    <m:MaterialButton ui:field="areaDropDownButton" text="Area" iconType="ARROW_DROP_DOWN" iconPosition="RIGHT" textColor="white" backgroundColor="green" activates="areaDropDown"/>
    <m:MaterialDropDown ui:field="areaDropDown" activator="areaDropDown" constrainWidth="true" />  
</m:MaterialContainer>

Java:

this.areaDropDown.addSelectionHandler(new SelectionHandler() 
{
    @Override
    public void onSelection(SelectionEvent event) {
        areaDropDownButton.setText(event.getSelectedItem().toString());
    }
});

GWT Material Demo: http://gwtmaterialdesign.github.io/gwt-material-demo/#!dropdown

Answer 1

Could't you use a MaterialListBox ? It seems to have the requirements for your current problem only the styling might be problematic for you

Answer 2

You could also use an UiHandler:

@UiHandler("areaDropDown")
void onDropdown(SelectionEvent event){
  areaDropDownButton.setText(event.getSelectedItem()).getText());
}

should work