SimpleListView.java

package be.selckin.swu.repeater;

import com.google.common.base.Preconditions;
import org.apache.wicket.Component;
import org.apache.wicket.markup.repeater.AbstractRepeater;
import org.apache.wicket.model.IModel;

import java.util.Collections;
import java.util.Iterator;
import java.util.List;

public abstract class SimpleListView<T> extends AbstractRepeater {

    private boolean reuseItems;

    protected SimpleListView(String id, IModel<? extends List<T>> model) {
        super(id, Preconditions.checkNotNull(model));
    }

    @Override
    protected void onConfigure() {
        super.onConfigure();
        setVisible(!getList().isEmpty());
    }

    @SuppressWarnings("unchecked")
    public final List<T> getList() {
        List<T> list = (List<T>) getDefaultModelObject();
        return list == null ? Collections.<T>emptyList() : list;
    }

    public boolean isReuseItems() {
        return reuseItems;
    }

    public SimpleListView<T> setReuseItems(boolean reuseItems) {
        this.reuseItems = reuseItems;
        return this;
    }

    @SuppressWarnings("unchecked")
    @Override
    protected final void onPopulate() {
        if (!getList().isEmpty()) {
            if (!reuseItems)
                removeAll();

            boolean hasChildren = size() != 0;
            for (int index = 0; index < getList().size(); index++) {
                String id = Integer.toString(index);
                Component item = null;
                if (hasChildren)
                    item = get(id);
                if (item == null)
                    add(create(id, new SimpleListViewItemModel<T>(this, index)));
            }
        } else {
            removeAll();
        }
    }

    protected abstract Component create(String id, IModel<T> model);

    @Override
    protected Iterator<Component> renderIterator() {
        return iterator();
    }

    @SuppressWarnings("unchecked")
    public final IModel<? extends List<T>> getModel() {
        return (IModel<? extends List<T>>) getDefaultModel();
    }

    public final void setModel(IModel<? extends List<T>> model) {
        setDefaultModel(model);
    }

    @SuppressWarnings("unchecked")
    public final List<T> getModelObject() {
        return (List<T>) getDefaultModelObject();
    }

    public static class SimpleListViewItemModel<T> implements IModel<T> {
        private final SimpleListView<T> listView;

        private final int index;

        public SimpleListViewItemModel(SimpleListView<T> listView, int index) {
            this.listView = listView;
            this.index = index;
        }

        @Override
        public T getObject() {
            return listView.getModelObject().get(index);
        }


        @Override
        public void setObject(T object) {
            listView.getModelObject().set(index, object);
        }

        @Override
        public void detach() {

        }
    }
}