ListViewLmlTag.java

package com.github.czyzby.lml.vis.parser.impl.tag;

import com.badlogic.gdx.scenes.scene2d.Actor;
import com.badlogic.gdx.scenes.scene2d.ui.Table;
import com.badlogic.gdx.utils.Array;
import com.github.czyzby.lml.parser.LmlParser;
import com.github.czyzby.lml.parser.impl.tag.actor.TableLmlTag;
import com.github.czyzby.lml.parser.tag.LmlActorBuilder;
import com.github.czyzby.lml.parser.tag.LmlTag;
import com.github.czyzby.lml.util.LmlUtilities;
import com.github.czyzby.lml.vis.parser.impl.tag.builder.ListViewLmlActorBuilder;
import com.kotcrab.vis.ui.util.adapter.ArrayAdapter;
import com.kotcrab.vis.ui.util.adapter.ListAdapter;
import com.kotcrab.vis.ui.widget.ListView;
import com.kotcrab.vis.ui.widget.ListView.ListViewTable;
import com.kotcrab.vis.ui.widget.ListView.UpdatePolicy;

/** Manages {@link ListView} widget. Note that list view is not actually an {@link Actor} - instead, its main table is
 * used as the main widget. When injecting the list view into fields or methods, expect {@link ListViewTable} instance
 * and extract {@link ListView} with {@link ListViewTable#getListView()} method. Mapped to "listView".
 *
 * <p>
 * Normally, list views are used to display collections of values. However, they can also be used as regular groups of
 * actors. If no {@link ListAdapter} is set with "adapter" attribute, a default implementation is provided. The default
 * adapter is prepared to handle regular actors, allowing the tag to have children. If a custom adapter is provided with
 * "adapter" attribute, this tag cannot have regular children.
 *
 * <p>
 * To set footer and header, use "footer=true" and "header=true" attributes in list view tag's children.
 *
 * <p>
 * Since list view manages a table and a scroll pane, it can have its attributes in its tag. However, table cell
 * attributes CANNOT be used: table is automatically built by the list adapter and should not be modified manually. If
 * you want a custom way of building the table, use another adapter implementation.
 *
 * <p>
 * By default, {@link ListView} will be in {@link UpdatePolicy#MANUAL} policy during creation to prevent the table from
 * being rebuilt during LML parsing. After the tag is closed, policy will be changed back to
 * {@link UpdatePolicy#IMMEDIATELY}. If you want to change this setting, do it manually after full construction of the
 * actor (onClose action can be used).
 *
 * @author MJ */
public class ListViewLmlTag extends TableLmlTag {
    private ListView<?> listView;

    public ListViewLmlTag(final LmlParser parser, final LmlTag parentTag, final StringBuilder rawTagData) {
        super(parser, parentTag, rawTagData);
    }

    @Override
    protected ListViewLmlActorBuilder getNewInstanceOfBuilder() {
        return new ListViewLmlActorBuilder();
    }

    @Override
    protected Table getNewInstanceOfActor(final LmlActorBuilder builder) {
        final ListAdapter<?> listAdapter = extractListAdapter((ListViewLmlActorBuilder) builder);
        listView = createListView(listAdapter, builder.getStyleName());
        LmlUtilities.getLmlUserObject(listView.getMainTable()).setData(listView);
        listView.setUpdatePolicy(UpdatePolicy.MANUAL); // Prevents the table from being rebuilt during creation.
        return listView.getMainTable();
    }

    /** @return managed {@link ListView}. */
    @Override
    public Object getManagedObject() {
        return listView;
    }

    /** @param listAdapter converts data to views.
     * @param styleName name of list view style applied to the view.
     * @return a new instance of ListView.
     * @param <Type> type of items stored by the list. */
    protected <Type> ListView<Type> createListView(final ListAdapter<Type> listAdapter, String styleName) {
        return new ListView<Type>(listAdapter, styleName);
    }

    /** @param builder may contain a custom adapter.
     * @return customized list adapter or the default implementation prepared to handle regular actors. */
    protected ListAdapter<?> extractListAdapter(final ListViewLmlActorBuilder builder) {
        return builder.getListAdapter() != null ? builder.getListAdapter()
                : new ArrayAdapter<Actor, Actor>(new Array<Actor>()) {
                    @Override
                    protected Actor createView(final Actor item) {
                        return item;
                    }
                };
    }

    @Override
    @SuppressWarnings("unchecked")
    protected void addChild(final Actor actor) {
        if (listView.getFooter() == actor || listView.getHeader() == actor) {
            return;
        }
        ((ListAdapter<Actor>) listView.getAdapter()).add(actor);
    }

    @Override
    protected void handlePlainTextLine(final String plainTextLine) {
        addChild(toLabel(plainTextLine));
    }

    @Override
    protected boolean hasComponentActors() {
        return true;
    }

    @Override
    protected Actor[] getComponentActors(final Actor actor) {
        return new Actor[] { listView.getScrollPane() };
    }

    @Override
    protected void doOnTagClose() {
        final ListView<?> listView = ((ListViewTable<?>) getActor()).getListView();
        listView.rebuildView();
        listView.setUpdatePolicy(UpdatePolicy.IMMEDIATELY);
        super.doOnTagClose();
    }
}