Java tutorial
/* * SoftVerticalScroll.java * * Created on August 16, 2007, 12:21 PM * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ package com.totsp.gwittir.client.fx.ui; import com.google.gwt.user.client.DOM; import com.google.gwt.user.client.Timer; import com.google.gwt.user.client.Window; import com.google.gwt.user.client.WindowResizeListener; import com.google.gwt.user.client.ui.Composite; import com.google.gwt.user.client.ui.FocusPanel; import com.google.gwt.user.client.ui.HorizontalPanel; import com.google.gwt.user.client.ui.MouseListener; import com.google.gwt.user.client.ui.MouseListenerAdapter; import com.google.gwt.user.client.ui.Panel; import com.google.gwt.user.client.ui.ScrollListener; import com.google.gwt.user.client.ui.SimplePanel; import com.google.gwt.user.client.ui.Widget; import com.totsp.gwittir.client.log.Level; import com.totsp.gwittir.client.log.Logger; /** * * @author <a href="mailto:cooper@screaming-penguin.com">Robert "kebernet" Cooper</a> */ public class SoftHorizontalScrollbar extends Composite { FocusPanel barTarget = new FocusPanel(); FocusPanel higherTarget = new FocusPanel(); FocusPanel lowerTarget = new FocusPanel(); ScrollListener scrollListener = new ScrollListener() { public void onScroll(Widget widget, int scrollLeft, int scrollTop) { refresh(); } }; SimplePanel bar = new SimplePanel(); SimplePanel base; SimplePanel higher = new SimplePanel(); SimplePanel lower = new SimplePanel(); SoftScrollArea target; private MouseListener barListener = new MouseListenerAdapter() { boolean inDrag = false; int start; public void onMouseLeave(Widget sender) { inDrag = false; } public void onMouseUp(Widget sender, int x, int y) { inDrag = false; } public void onMouseDown(Widget sender, int x, int y) { inDrag = true; start = x; } public void onMouseMove(Widget sender, int x, int y) { if (inDrag) { float newPercent = (float) ((x - start) + lower.getOffsetWidth()) / (float) base.getOffsetWidth(); Logger.getAnonymousLogger().log(Level.SPAM, x + " " + newPercent, null); int newPosition = Math.round( (target.getOffsetWidth() + target.getMaxHorizontalScrollPosition()) * newPercent) + x; target.setHorizontalScrollPosition(newPosition); } } }; private MouseListener higherListener = new MouseListenerAdapter() { public void onMouseDown(Widget sender, int x, int y) { float newPercent = (float) (x + lower.getOffsetWidth() + bar.getOffsetWidth()) / (float) base.getOffsetWidth(); int newPosition = Math .round((target.getOffsetWidth() + target.getMaxHorizontalScrollPosition()) * newPercent) - (target.getOffsetWidth() / 2); target.setHorizontalScrollPosition(newPosition); } }; private MouseListener lowerListener = new MouseListenerAdapter() { public void onMouseDown(Widget sender, int x, int y) { float newPercent = (float) x / (float) base.getOffsetWidth(); int newPosition = Math .round((target.getOffsetWidth() + target.getMaxHorizontalScrollPosition()) * newPercent) - (target.getOffsetWidth() / 2); Logger.getAnonymousLogger().log(Level.SPAM, "New Position: " + newPosition, null); target.setHorizontalScrollPosition(newPosition); } }; private WindowResizeListener windowListener = new WindowResizeListener() { public void onWindowResized(int width, int height) { refresh(); } }; /** Creates a new instance of SoftVerticalScroll */ public SoftHorizontalScrollbar(SoftScrollArea target) { this.target = target; this.base = new SimplePanel(); Panel horizontal = new HorizontalPanel(); this.base.setWidget(horizontal); super.initWidget(this.base); this.higherTarget.setWidget(this.higher); this.barTarget.setWidget(this.bar); this.lowerTarget.setWidget(this.lower); horizontal.add(lowerTarget); horizontal.add(barTarget); horizontal.add(higherTarget); this.setStyleName("gwittir-SoftHorizontalScrollbar"); this.bar.setStyleName("bar"); this.lower.setStyleName("lower"); this.higher.setStyleName("higher"); DOM.setStyleAttribute(this.lower.getElement(), "overflow", "hidden"); DOM.setStyleAttribute(this.bar.getElement(), "overflow", "hidden"); DOM.setStyleAttribute(this.higher.getElement(), "overflow", "hidden"); DOM.setStyleAttribute(this.getElement(), "overflow", "hidden"); } protected MouseListener getBarListener() { return barListener; } protected MouseListener getHigherListener() { return this.higherListener; } protected MouseListener getLowerListener() { return this.lowerListener; } protected void onAttach() { super.onAttach(); target.addScrollListener(this.scrollListener); Window.addWindowResizeListener(this.windowListener); this.lowerTarget.addMouseListener(this.getLowerListener()); this.higherTarget.addMouseListener(this.getHigherListener()); this.barTarget.addMouseListener(this.getBarListener()); Timer t = new Timer() { public void run() { target.setScrollPosition(target.getScrollPosition()); refresh(); } }; t.schedule(10); } protected void onDetach() { super.onDetach(); Window.removeWindowResizeListener(this.windowListener); this.lowerTarget.removeMouseListener(this.getLowerListener()); this.higherTarget.removeMouseListener(this.getHigherListener()); this.barTarget.removeMouseListener(this.getBarListener()); target.removeScrollListener(this.scrollListener); } public void refresh() { int currentWidth = this.getOffsetWidth(); float pageSize = (float) target.getOffsetWidth() / (float) (target.getMaxHorizontalScrollPosition() + target.getOffsetWidth()); //GWT.log("Page sisze " + pageSize, null); float scrollPercentage = (float) target.getHorizontalScrollPosition() / (target.getMaxHorizontalScrollPosition() + 1); //GWT.log("Scroll Percentage " + scrollPercentage, null); int lowerWidth = Math .round((currentWidth - Math.round((float) currentWidth * pageSize)) * scrollPercentage); //GWT.log("Lower width " + lowerWidth, null); if (lowerWidth == 0) { lowerWidth = 1; } this.lower.setWidth(lowerWidth + "px"); int barWidth = Math.round(currentWidth * pageSize); //GWT.log("Bar width " + barWidth, null); if (barWidth >= 0) { this.bar.setWidth(barWidth + "px"); } int higherWidth = currentWidth - lowerWidth - barWidth; if (higherWidth >= 0) { this.higher.setWidth(higherWidth + "px"); } this.lower.setHeight(this.getOffsetHeight() + "px"); this.bar.setHeight(this.getOffsetHeight() + "px"); this.higher.setHeight(this.getOffsetHeight() + "px"); } public void setBarWidget(Widget w) { this.bar.setWidget(w); DOM.setStyleAttribute(this.bar.getElement(), "overflow", "hidden"); } public void setHigherWidget(Widget w) { this.higher.setWidget(w); DOM.setStyleAttribute(this.higher.getElement(), "overflow", "hidden"); } public void setLowerWidget(Widget w) { this.lower.setWidget(w); DOM.setStyleAttribute(this.lower.getElement(), "overflow", "hidden"); } }