AlgebraDockPanelW.java

package org.geogebra.web.web.gui.layout.panels;

import org.geogebra.common.main.App;
import org.geogebra.common.main.Feature;
import org.geogebra.common.main.App.InputPosition;
import org.geogebra.web.html5.gui.util.MathKeyboardListener;
import org.geogebra.web.web.gui.layout.DockPanelW;
import org.geogebra.web.web.gui.layout.DockSplitPaneW;
import org.geogebra.web.web.gui.view.algebra.AlgebraViewW;
import org.geogebra.web.web.gui.view.algebra.LatexTreeItem;
import org.geogebra.web.web.gui.view.algebra.LatexTreeItemController;
import org.geogebra.web.web.gui.view.algebra.RadioTreeItem;

import com.google.gwt.core.client.Scheduler;
import com.google.gwt.core.client.Scheduler.ScheduledCommand;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.resources.client.ResourcePrototype;
import com.google.gwt.user.client.ui.ScrollPanel;
import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.Widget;

public class AlgebraDockPanelW extends DockPanelW {

	ScrollPanel algebrap;
	SimplePanel simplep;
	AlgebraViewW aview = null;
	private int savedScrollPosition;

	public AlgebraDockPanelW(App app1) {
		super(
				App.VIEW_ALGEBRA,	// view id 
				"AlgebraWindow", 			// view title phrase
				null,						// toolbar string
				true,						// style bar?
				2, 							// menu order
				'A'							// menu shortcut
			);
		if (app1.has(Feature.DYNAMIC_STYLEBAR)) {
			setViewImage(getResources().settings());
		} else {
			setViewImage(getResources().styleBar_algebraView());
		}
	}

	@Override
	protected Widget loadComponent() {
		if (algebrap == null) {
			algebrap = new ScrollPanel();//temporarily
			algebrap.setSize("100%", "100%");
			algebrap.setAlwaysShowScrollBars(false);
		}
		if (app != null) {
			// force loading the algebra view,
			// as loadComponent should only load when needed
			setAlgebraView((AlgebraViewW) app.getAlgebraView());
			aview.setInputPanel();
		}
		return algebrap;
	}

	@Override
	protected Widget loadStyleBar() {
		return aview.getStyleBar(true);
	}

	public void setAlgebraView(final AlgebraViewW av) {
		if (av != aview) {
			if (aview != null && simplep != null) {
				simplep.remove(aview);
				algebrap.remove(simplep);
			}

			simplep = new SimplePanel(aview = av);
			algebrap.add(simplep);
			simplep.addStyleName("algebraSimpleP");
			algebrap.addStyleName("algebraPanel");
			algebrap.addDomHandler(new ClickHandler() {

				@Override
				public void onClick(ClickEvent event) {
					int bt = simplep.getAbsoluteTop()
							+ simplep.getOffsetHeight();
					if (event.getClientY() > bt) {
						app.getSelectionManager().clearSelectedGeos();
						av.resetItems(true);
					}
				}
			}, ClickEvent.getType());
		}
	}

	public ScrollPanel getAbsolutePanel() {
	    return algebrap;
    }

	@Override
	public void onResize() {
		DockSplitPaneW split = getParentSplitPane();
		if (split != null && split.isForcedLayout()) {
			if (aview != null) {
				int w = getOffsetWidth();
				aview.setUserWidth(w);
			}
		}
		if (aview != null) {
			aview.resize();
		}
	}

	@Override
    public ResourcePrototype getIcon() {
		return getResources().menu_icon_algebra();
	}

	/**
	 * scrolls to a specific position of the panel
	 * 
	 * @param position
	 *            to scroll to.
	 */
	public void scrollTo(int position) {
		if (this.algebrap != null) {
			this.algebrap.setVerticalScrollPosition(position);
		}
	}

	/**
	 * scrolls to the bottom of the panel
	 */
	public void scrollToBottom(){
		if (this.algebrap != null) {
			this.algebrap.scrollToBottom();
		}
	}

	@Override
	public MathKeyboardListener getKeyboardListener() {
		if (app.getInputPosition() != InputPosition.algebraView) {
			return null;
		}
		return ((AlgebraViewW) app.getAlgebraView()).getActiveTreeItem();
	}

	public MathKeyboardListener updateKeyboardListener(MathKeyboardListener ml) {
		if (aview.getInputTreeItem() != ml) {
			return ml;
		}

		// if no retex editor yet
		if (!(ml instanceof LatexTreeItem)) {
			return ml;
		}
		LatexTreeItemController itemController = ((LatexTreeItem) ml).getLatexController();
		itemController.initAndShowKeyboard(false);
		return itemController.getRetexListener();
	}

	/**
	 * Scroll to the item that is selected.
	 */
	public void scrollToActiveItem() {

		final RadioTreeItem item = aview == null ? null
				: aview.getActiveTreeItem();
		if (item == null) {
			return;
		}

		if (item.isInputTreeItem()) {
			Scheduler.get().scheduleDeferred(new ScheduledCommand() {

				@Override
				public void execute() {

					algebrap.scrollToBottom();
				}
			});
			return;
		}
		doScrollToActiveItem();
	}

	/**
	 * Saves the current scroll position of the dock panel.
	 */
	public void saveScrollPosition() {
		savedScrollPosition = algebrap.getVerticalScrollPosition();
	}

	private void doScrollToActiveItem() {
		final RadioTreeItem item = aview.getActiveTreeItem();

		int spH = algebrap.getOffsetHeight();

		int top = item.getElement().getOffsetTop();

		int relTop = top - savedScrollPosition;

		if (spH < relTop + item.getOffsetHeight()) {

			int pos = top + item.getOffsetHeight() - spH;
			algebrap.setVerticalScrollPosition(pos);
		} else {
			// algebrap.setVerticalScrollPosition(savedScrollPosition);
		}
	}
}