gojs

<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"/> <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no, viewport-fit=cover"/> <link rel="stylesheet" href="../assets/css/style.css"/>  <title> GoJS Commands -- Northwoods Software </title> <link rel="stylesheet" href="../assets/css/prism.css" /> </head> <script> window.diagrams = []; window.goCode = function(pre, w, h, parentid, animation) { window.diagrams.push([pre, w, h, parentid, animation]); } </script> <body> <nav id="navTop" class="w-full z-30 top-0 text-white bg-nwoods-primary"> <div class="w-full container max-w-screen-lg mx-auto flex flex-wrap sm:flex-nowrap items-center justify-between mt-0 py-2"> <div class="md:pl-4"> <a class="text-white hover:text-white no-underline hover:no-underline font-bold text-2xl lg:text-4xl rounded-lg hover:bg-nwoods-secondary " href="../"> <h1 class="mb-0 p-1 ">GoJS</h1> </a> </div> <button id="topnavButton" class="rounded-lg sm:hidden focus:outline-none focus:ring" aria-label="Navigation"> <svg fill="currentColor" viewBox="0 0 20 20" class="w-6 h-6"> <path id="topnavOpen" fill-rule="evenodd" d="M3 5a1 1 0 011-1h12a1 1 0 110 2H4a1 1 0 01-1-1zM3 10a1 1 0 011-1h12a1 1 0 110 2H4a1 1 0 01-1-1zM9 15a1 1 0 011-1h6a1 1 0 110 2h-6a1 1 0 01-1-1z" clip-rule="evenodd"></path> <path id="topnavClosed" class="hidden" fill-rule="evenodd" d="M4.293 4.293a1 1 0 011.414 0L10 8.586l4.293-4.293a1 1 0 111.414 1.414L11.414 10l4.293 4.293a1 1 0 01-1.414 1.414L10 11.414l-4.293 4.293a1 1 0 01-1.414-1.414L8.586 10 4.293 5.707a1 1 0 010-1.414z" clip-rule="evenodd"></path> </svg> </button> <div id="topnavList" class="hidden sm:block items-center w-auto mt-0 text-white p-0 z-20"> <ul class="list-reset list-none font-semibold flex justify-end flex-wrap sm:flex-nowrap items-center px-0 pb-0"> <li class="p-1 sm:p-0"><a class="topnav-link" href="../learn/">Learn</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="../samples/">Samples</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="../intro/">Intro</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="../api/">API</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="https://www.nwoods.com/products/register.html">Register</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="../download.html">Download</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="https://forum.nwoods.com/c/gojs/11">Forum</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="https://www.nwoods.com/contact.html" target="_blank" rel="noopener" onclick="getOutboundLink('https://www.nwoods.com/contact.html', 'contact');">Contact</a></li> <li class="p-1 sm:p-0"><a class="topnav-link" href="https://www.nwoods.com/sales/index.html" target="_blank" rel="noopener" onclick="getOutboundLink('https://www.nwoods.com/sales/index.html', 'buy');">Buy</a></li> </ul> </div> </div> <hr class="border-b border-gray-600 opacity-50 my-0 py-0" /> </nav> <div class="md:flex flex-col md:flex-row md:min-h-screen w-full max-w-screen-xl mx-auto"> <div id="navSide" class="flex flex-col w-full md:w-40 lg:w-48 text-gray-700 bg-white flex-shrink-0"> <div class="flex-shrink-0 px-8 py-4"> <button id="navButton" class="rounded-lg md:hidden focus:outline-none focus:ring" aria-label="Navigation"> <svg fill="currentColor" viewBox="0 0 20 20" class="w-6 h-6"> <path id="navOpen" fill-rule="evenodd" d="M3 5a1 1 0 011-1h12a1 1 0 110 2H4a1 1 0 01-1-1zM3 10a1 1 0 011-1h12a1 1 0 110 2H4a1 1 0 01-1-1zM9 15a1 1 0 011-1h6a1 1 0 110 2h-6a1 1 0 01-1-1z" clip-rule="evenodd"></path> <path id="navClosed" class="hidden" fill-rule="evenodd" d="M4.293 4.293a1 1 0 011.414 0L10 8.586l4.293-4.293a1 1 0 111.414 1.414L11.414 10l4.293 4.293a1 1 0 01-1.414 1.414L10 11.414l-4.293 4.293a1 1 0 01-1.414-1.414L8.586 10 4.293 5.707a1 1 0 010-1.414z" clip-rule="evenodd"></path> </svg> </button> </div> <nav id="navList" class="min-h-screen hidden md:block sidebar-nav flex-grow px-1 lg:px-4 pb-4 md:pb-0 md:overflow-y-auto break-words"> <a href="index.html">Basics</a> <a href="buildingObjects.html">Building Parts</a> <a href="usingModels.html">Using Models</a> <a href="dataBinding.html">Data Binding</a> <a href="react.html">GoJS with React</a> <a href="angular.html">GoJS with Angular</a> <a href="textBlocks.html">TextBlocks</a> <a href="shapes.html">Shapes</a> <a href="pictures.html">Pictures</a> <a href="panels.html">Panels</a> <a href="tablePanels.html">Table Panels</a> <a href="brush.html">Brushes</a> <a href="sizing.html">Sizing Objects</a> <a href="itemArrays.html">Item Arrays</a> <a href="changedEvents.html">Changed Events</a> <a href="transactions.html">Transactions</a> <a href="viewport.html">Coordinates</a> <a href="initialView.html">Initial View</a> <a href="collections.html">Collections</a> <a href="links.html">Links</a> <a href="linkLabels.html">Link Labels</a> <a href="connectionPoints.html">Link Points</a> <a href="ports.html">Ports</a> <a href="nodes.html">Nodes</a> <a href="debugging.html">Debugging</a> <a href="layouts.html">Layouts</a> <a href="trees.html">Trees</a> <a href="subtrees.html">SubTrees</a> <a href="groups.html">Groups</a> <a href="subgraphs.html">SubGraphs</a> <a href="sizedGroups.html">Sized Groups</a> <a href="selection.html">Selection</a> <a href="highlighting.html">Highlighting</a> <a href="animation.html">Animation</a> <a href="toolTips.html">ToolTips</a> <a href="contextmenus.html">Context Menus</a> <a href="events.html">Diagram Events</a> <a href="tools.html">Tools</a> <a href="commands.html">Commands</a> <a href="permissions.html">Permissions</a> <a href="validation.html">Validation</a> <a href="HTMLInteraction.html">HTML Interaction</a> <a href="layers.html">Layers & Z-ordering</a> <a href="palette.html">Palette</a> <a href="overview.html">Overview</a> <a href="resizing.html">Resizing Diagrams</a> <a href="replacingDeleting.html">Replacing and Deleting</a> <a href="buttons.html">Buttons</a> <a href="templateMaps.html">Template Maps</a> <a href="legends.html">Legends and Titles</a> <a href="extensions.html">Extensions</a> <a href="geometry.html">Geometry Strings</a> <a href="grids.html">Grid Patterns</a> <a href="graduatedPanels.html">Graduated Panels</a> <a href="makingImages.html">Diagram Images</a> <a href="makingSVG.html">Diagram SVG</a> <a href="printing.html">Printing</a> <a href="serverSideImages.html">Server-side Images</a> <a href="nodeScript.html">GoJS in Node.js</a> <a href="testing.html">Testing</a> <a href="storage.html">Storage</a> <a href="performance.html">Performance</a> <a href="source.html">Building from Source</a> <a href="platforms.html">Platforms</a> <a href="deployment.html">Deployment</a> </nav> </div> <div class="pt-4 px-2 md:px-0 lg:px-4 pb-16 w-full overflow-hidden"> <h1>Commands</h1> <p> Commands such as <b>Delete</b> or <b>Paste</b> or <b>Undo</b> are implemented by the <a>CommandHandler</a> class. </p> <p> Keyboard events, like mouse and touch events, always go to the <a>Diagram.currentTool</a>. The current tool, when the user is not performing some gesture, is the same as the <a>Diagram.defaultTool</a>, which normally is the <a>Diagram.toolManager</a>. The <a>ToolManager</a> handles keyboard events by delegating them to the <a>Diagram.commandHandler</a>. </p> <p> Basically, the diagram handles a keyboard event, creates an <a>InputEvent</a> describing it, and then calls <a>ToolManager.doKeyDown</a>. That in turn just calls <a>CommandHandler.doKeyDown</a>. The same sequence happens for key-up events. </p> <p> Please note that the handling of keyboard commands depends on the diagram getting focus and then getting keyboard events. Do not apply any styling such as <pre class="lang-css"><code>canvas:focus { display: none; }</code></pre>. </p> <h2 id="KeyboardCommandBindings">Keyboard command bindings</h2> <p> The <a>CommandHandler</a> implements the following command bindings for keyboard input: </p> <ul> <li>Del & Backspace invoke <a>CommandHandler.deleteSelection</a></li> <li>Ctrl-X & Shift-Del invoke <a>CommandHandler.cutSelection</a></li> <li>Ctrl-C & Ctrl-Insert invoke <a>CommandHandler.copySelection</a></li> <li>Ctrl-V & Shift-Insert invoke <a>CommandHandler.pasteSelection</a></li> <li>Ctrl-A invokes <a>CommandHandler.selectAll</a></li> <li>Ctrl-Z & Alt-Backspace invoke <a>CommandHandler.undo</a></li> <li>Ctrl-Y & Alt-Shift-Backspace invoke <a>CommandHandler.redo</a></li> <li>Up & Down & Left & Right (arrow keys) call <a>Diagram.scroll</a></li> <li>PageUp & PageDown call <a>Diagram.scroll</a></li> <li>Home & End call <a>Diagram.scroll</a></li> <li>Space invokes <a>CommandHandler.scrollToPart</a></li> <li>Keypad-- (minus) invokes <a>CommandHandler.decreaseZoom</a></li> <li>Keypad-+ (plus) invokes <a>CommandHandler.increaseZoom</a></li> <li>Ctrl-0 invokes <a>CommandHandler.resetZoom</a></li> <li>Shift-Z invokes <a>CommandHandler.zoomToFit</a>; repeat to return to the original scale and position</li> <li>Ctrl-G invokes <a>CommandHandler.groupSelection</a></li> <li>Ctrl-Shift-G invokes <a>CommandHandler.ungroupSelection</a></li> <li>F2 invokes <a>CommandHandler.editTextBlock</a></li> <li>Menu Key invokes <a>CommandHandler.showContextMenu</a></li> <li>Esc invokes <a>CommandHandler.stopCommand</a></li> </ul> <p> On a Mac the Command key is used as the modifier instead of the Control key. </p> <p> At the current time there are no keyboard bindings for commands such as <a>CommandHandler.collapseSubGraph</a>, <a>CommandHandler.collapseTree</a>, <a>CommandHandler.expandSubGraph</a>, or <a>CommandHandler.expandTree</a>. </p> <p> If you want to have a different behavior for the arrow keys, consider using the sample class extended from <a>CommandHandler</a>: <a href="../extensions/DrawCommandHandler.js">DrawCommandHandler</a>, which implements options for having the arrow keys move the selection or change the selection. </p> <p> That DrawCommandHandler extension also demonstrates a customization of the <b>Copy</b> and <b>Paste</b> commands to automatically shift the location of pasted copies. </p> <h2 id="CommandHandler">CommandHandler</h2> <p> The <a>CommandHandler</a> class implements pairs of methods: a method to execute a command and a predicate that is true when the command may be executed. For example, for the <b>Copy</b> command, there is a <a>CommandHandler.copySelection</a> method and a <a>CommandHandler.canCopySelection</a> method. </p> <p> Keyboard event handling always calls the "can..." predicate first. Only if that returns true does it actually call the method to execute the command. </p> <p> There are a number of properties that you can set to affect the CommandHandler's standard behavior. For example, if you want to allow the user to group selected parts together with the <a>CommandHandler.groupSelection</a>, you will need to set <a>CommandHandler.archetypeGroupData</a> to a group node data object: </p> <pre class="lang-js"><code> diagram.commandHandler.archetypeGroupData = { key: "Group", isGroup: true, color: "blue" }; </code></pre> <p> That data object is copied and added to the model as the new group data object by <a>CommandHandler.groupSelection</a>. </p> <p> If you want to add your own keyboard bindings, you can override the <a>CommandHandler.doKeyDown</a> method. For example, to support using the "T" key to collapse or expand the currently selected <a>Group</a>: </p> <pre class="lang-js"><code> myDiagram.commandHandler.doKeyDown = function() { var e = myDiagram.lastInput; var cmd = myDiagram.commandHandler; if (e.key === "T") { // could also check for e.control or e.shift if (cmd.canCollapseSubGraph()) { cmd.collapseSubGraph(); } else if (cmd.canExpandSubGraph()) { cmd.expandSubGraph(); } } else { // call base method with no arguments go.CommandHandler.prototype.doKeyDown.call(cmd); } }; </code></pre> <p> Do not forget to call the base method in order to handle all of the keys that your method does not handle. </p> <p class="box bg-info"> Note that calling the base method involves getting the base class's prototype's method. If the base method takes arguments, be sure to pass arguments to the call to the base method. </p> <h2 id="UpdatingCommandUI">Updating command UI</h2> <p> It is common to have HTML elements outside of the diagram that invoke commands. You can use the <a>CommandHandler</a>'s "can..." predicates to enable or disable UI that would invoke the command. </p> <pre class="lang-js" id="commands"><code> // allow the group command to execute diagram.commandHandler.archetypeGroupData = { key: "Group", isGroup: true, color: "blue" }; // modify the default group template to allow ungrouping diagram.groupTemplate.ungroupable = true; var nodeDataArray = [ { key: "Alpha" }, { key: "Beta" }, { key: "Delta", group: "Epsilon" }, { key: "Gamma", group: "Epsilon" }, { key: "Epsilon", isGroup: true } ]; var linkDataArray = [ { from: "Alpha", to: "Beta" }, { from: "Beta", to: "Beta" }, { from: "Gamma", to: "Delta" }, { from: "Delta", to: "Alpha" } ]; diagram.model = new go.GraphLinksModel(nodeDataArray, linkDataArray); // enable or disable a particular button function enable(name, ok) { var button = document.getElementById(name); if (button) button.disabled = !ok; } // enable or disable all command buttons function enableAll() { var cmdhnd = diagram.commandHandler; enable("SelectAll", cmdhnd.canSelectAll()); enable("Cut", cmdhnd.canCutSelection()); enable("Copy", cmdhnd.canCopySelection()); enable("Paste", cmdhnd.canPasteSelection()); enable("Delete", cmdhnd.canDeleteSelection()); enable("Group", cmdhnd.canGroupSelection()); enable("Ungroup", cmdhnd.canUngroupSelection()); enable("Undo", cmdhnd.canUndo()); enable("Redo", cmdhnd.canRedo()); } // notice whenever the selection may have changed diagram.addDiagramListener("ChangedSelection", function(e) { enableAll(); }); // notice when the Paste command may need to be reenabled diagram.addDiagramListener("ClipboardChanged", function(e) { enableAll(); }); // notice whenever a transaction or undo/redo has occurred diagram.addModelChangedListener(function(e) { if (e.isTransactionFinished) enableAll(); }); // perform initial enablements after everything has settled down setTimeout(enableAll, 100); // make the diagram accessible to button onclick handlers myDiagram = diagram; // calls enableAll() due to Model Changed listener myDiagram.undoManager.isEnabled = true; </code></pre> <script>goCode("commands", 600, 150)</script> <input id="SelectAll" type="button" onclick="myDiagram.commandHandler.selectAll()" value="Select All" /> <input id="Cut" type="button" onclick="myDiagram.commandHandler.cutSelection()" value="Cut" /> <input id="Copy" type="button" onclick="myDiagram.commandHandler.copySelection()" value="Copy" /> <input id="Paste" type="button" onclick="myDiagram.commandHandler.pasteSelection()" value="Paste" /> <input id="Delete" type="button" onclick="myDiagram.commandHandler.deleteSelection()" value="Delete" /> <input id="Group" type="button" onclick="myDiagram.commandHandler.groupSelection()" value="Group" /> <input id="Ungroup" type="button" onclick="myDiagram.commandHandler.ungroupSelection()" value="Ungroup" /> <input id="Undo" type="button" onclick="myDiagram.commandHandler.undo()" value="Undo" /> <input id="Redo" type="button" onclick="myDiagram.commandHandler.redo()" value="Redo" /> <p> Each button is implemented in the following fashion: </p> <pre class="lang-html"><code> <input id="SelectAll" type="button" onclick="myDiagram.commandHandler.selectAll()" value="Select All" /> </code></pre> <p> Whenever the selection changes or whenever a transaction or undo or redo occurs, the enableAll function is called to update the "disabled" property of each of the buttons. </p> <h2 id="Accessibility">Accessibility</h2> <p> Since <b>GoJS</b> is based on the HTML Canvas element, making an app that is accessible to screen-readers or other accessibility devices is a matter of generating fallback content outside of GoJS, just as you would generate fallback content separate from any HTML Canvas application. </p> <p> Although much of the predefined functionality of the <a>CommandHandler</a> is accessible with keyboard commands or the default context menu, not all of it is, and the functionality of the <a>Tool</a>s mostly depends on mouse or touch events. We recommend that you implement alternative mechanisms specific to your application for those tools that you want your users to access without a pointing device. </p> <h2 id="MoreCommandHandlerOverrideExamples">More CommandHandler override examples</h2> <p> Stop CTRL+Z/CTRL+Y from doing an undo/redo, but still allow <a>CommandHandler.undo</a> and <a>CommandHandler.redo</a> to be called programatically: </p> <pre class="lang-js"><code> myDiagram.commandHandler.doKeyDown = function() { var e = myDiagram.lastInput; // The meta (Command) key substitutes for "control" for Mac commands var control = e.control || e.meta; var key = e.key; // Quit on any undo/redo key combination: if (control && (key === 'Z' || key === 'Y')) return; // call base method with no arguments (default functionality) go.CommandHandler.prototype.doKeyDown.call(this); }; </code></pre> </div> </div> <div class="bg-nwoods-primary"> <section class="max-w-screen-lg text-white container mx-auto py-2 px-12"> <p id="version" class="leading-none mb-2 my-4">GoJS</p> </section> </div><footer class="bg-nwoods-primary text-white"> <div class="container max-w-screen-lg mx-auto px-8"> <div class="w-full py-6"> <div class="max-w-screen-lg xl:max-w-screen-xl mx-auto px-4 sm:px-6 md:px-8"> <ul class="text-sm font-medium pb-14 sm:pb-20 grid grid-cols-1 sm:grid-cols-3 gap-y-10"> <li class="list-none row-span-2"> <h2 class="text-base font-semibold tracking-wide">GoJS</h2> <ul class="list-none space-y-4 md:space-y-1 px-0"> <li> <a href="../samples/index.html">Samples</a> </li> <li> <a href="../learn/index.html">Learn</a> </li> <li> <a href="../intro/index.html">Intro</a> </li> <li> <a href="../api/index.html">API</a> </li> <li> <a href="../changelog.html">Changelog</a> </li> <li> <a href="https://github.com/NorthwoodsSoftware/GoJS">GitHub</a> </li> </ul> </li> <li class="list-none row-span-2"> <h2 class="text-base font-semibold tracking-wide">Support</h2> <ul class="list-none space-y-4 md:space-y-1 px-0"> <li> <a href="https://www.nwoods.com/contact.html" target="_blank" rel="noopener" onclick="getOutboundLink('https://www.nwoods.com/contact.html', 'contact');">Contact</a> </li> <li> <a href="https://forum.nwoods.com/c/gojs">Forum</a> </li> <li> <a href="https://www.nwoods.com/app/activate.aspx?sku=gojs">Activate</a> </li> <li> <a href="https://www.nwoods.com/sales/index.html" target="_blank" rel="noopener" onclick="getOutboundLink('https://www.nwoods.com/sales/index.html', 'buy');">Buy</a> </li> <li> <a href="https://www.youtube.com/channel/UC9We8EoX596-6XFjJDtZIDg">Videos</a> </li> </ul> </li> <li class="list-none row-span-2"> <h2 class="text-base font-semibold tracking-wide">Company</h2> <ul class="list-none space-y-4 md:space-y-1 px-0"> <li> <a href="https://www.nwoods.com">Northwoods</a> </li> <li> <a href="https://www.nwoods.com/about.html">About Us</a> </li> <li> <a href="https://www.nwoods.com/contact.html">Contact Us</a> </li> <li> <a href="https://twitter.com/northwoodsgo">Twitter</a> </li> </ul> </li> </ul> <p class="text-sm text-gray-100 md:mb-6"> Copyright 1998-2021 <a class="text-white" href="https://www.nwoods.com">Northwoods Software</a> </p> </div> </div> </footer> </body> <script async src="https://www.googletagmanager.com/gtag/js?id=UA-1506307-5"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'UA-1506307-5'); var getOutboundLink = function(url, label) { gtag('event', 'click', { 'event_category': 'outbound', 'event_label': label, 'transport_type': 'beacon' }); } // topnav var topButton = document.getElementById("topnavButton"); var topnavList = document.getElementById("topnavList"); topButton.addEventListener("click", function() { this.classList.toggle("active"); topnavList.classList.toggle("hidden"); document.getElementById("topnavOpen").classList.toggle("hidden"); document.getElementById("topnavClosed").classList.toggle("hidden"); }); </script> <script src="../assets/js/prism.js"></script> <script src="../release/go.js"></script> <script src="../assets/js/goDoc.js"></script> <script> document.addEventListener("DOMContentLoaded", function() { if (window.go) document.getElementById('version').textContent = "GoJS version " + go.version; if (window.goDoc) window.goDoc(); var d = window.diagrams; for (var i = 0; i < d.length; i++) { var dargs = d[i]; goCodeExecute(dargs[0], dargs[1], dargs[2], dargs[3], dargs[4]); } if (window.extra) window.extra(); }); </script> </html>