PANIOV


public class EnumListBoxEditor<T extends Enum<T>> implements IsWidget, LeafValueEditor<T> {

    private ListBox listBox;    private Class<T> enumType;
    public EnumListBoxEditor(Class<T> tClass) {
        listBox = new ListBox();        this.enumType = tClass;        for(T e : enumType.getEnumConstants()) {
            listBox.addItem(e.name());        }
    }

    @Override    public Widget asWidget() {
        return listBox;    }

    @Override    public void setValue(T language) {
        listBox.setSelectedIndex(language.ordinal());    }

    @Override    public T getValue() {
        int index = listBox.getSelectedIndex();        T result = null;        for (T e : enumType.getEnumConstants()) {
            String itemName = listBox.getValue(index);            if (e.name().equals(itemName)) {
               result = e;            }
        }
        return result;    }

    public void setEnabled(boolean isEnabled){
        listBox.setEnabled(isEnabled);    }

}

Thus this approach is acceptable the best way to use ListBox with any Enum or bean that implement HasLabel interface is ValueListBox component e.g.:

@UiField(provided = true)
ValueListBox<TeamDTO> team;

this.team = new ValueListBox<TeamDTO>(new HasLabelRenderer<TeamDTO>(), new IdentityProvidesKey<TeamDTO>());

public class HasLabelRenderer<T extends HasLabel> extends AbstractRenderer<T>{

    @Override    public String render(HasLabel object) {
        return object == null ? "" : object.getLabel();    }

}

public class IdentityProvidesKey<T extends Identity> implements ProvidesKey<T> {
    @Override    public Object getKey(T item) {
        return item == null ? null: item.getId();    }
}

Thursday, June 18, 2015

JAVA - example of use in overrided method generic type of class that extends interface

public class HasLabelRenderer<T extends HasLabel> extends AbstractRenderer<T>{

    @Override    public String render(HasLabel object) {
        return object == null ? "" : object.getLabel();    }

}

This approach is possible due to the fact that in generics e.g. Bounded Type Parameter the type can be of the upper type it is extended. For instance, in example above the type T in HasLabelRenderer<T extends HasLabel> can be of type HasLabel interface.

Thursday, June 11, 2015

Angular JS - This is a great article explaining why will Angular 2 rock!

http://buff.ly/1f2A4Qc