This intro page explains how to use GoJS Diagrams alongside other HTML elements in a webapp.
For custom Text Editors, Context Menus, and ToolTips, which are invoked and hidden via GoJS tool operations, it is best to use the HTMLInfo class.
HTMLInfo
is described in the second section of this page.
Generally, GoJS can interact with the rest of the page via JavaScript that programmatically moves and modifies GoJS objects and the Diagram. If you have not read about programmatically interacting with Parts and the Model, there is a GraphObject Manipulation tutorial for this purpose.
To help programmers get started with HTML controls we have implemented a simple Data Inspector Extension, an HTML-based property editor that displays and allows editing of data for the selected Part.
The Data Inspector chiefly works via a "ChangedSelection"
Diagram Listener. When triggered, it populates HTML Fields.
Editing those fields and clicking away then update the selected Part by calling diagram.model.setDataProperty
to update the model.
GoJS does not depend on jQuery, but the two can be used together. The HTML Interaction Sample places a GoJS Palette inside of a jQuery movable window, and a data inspector that modifies the current selected node inside another.
jQuery normally sets the $
variable. If you are copying code from our samples or documentation, be aware that we usually do this:
const $ = go.GraphObject.make;
so that uses of $
in our examples will build GraphObjects and other GoJS objects. Caution:
calling jQuery when trying to build GoJS objects will cause unusual and cryptic errors. So you should locally assign the $
variable or use
a different variable for building GoJS objects.
When a browser element gets focus, some browsers scroll that element into view as much as possible. Because this behavior may be unwelcome in some web apps, the Diagram.scrollsPageOnFocus property defaults to false. However you may want to set this property to true in order to get the standard behavior.
You can remove the outline while the Diagram is in focus. This is a CSS effect, not a GoJS effect, and can be removed by removing the CSS outline from all HTML elements inside the Diagram div:
/* affect all elements inside myDiagramDiv */
#myDiagramDiv * {
outline: none;
-webkit-tap-highlight-color: rgba(255, 255, 255, 0); /* mobile webkit */
}
Use the HTMLInfo class to display custom HTML page elements, such as a context menu, tooltip, or text editor made of HTML.
Properties that can be set to an instance of HTMLInfo
include:
When replacing GoJS functionality with custom functionality, the main concern is when to show and hide the custom content. HTMLInfo
does this
with two settable functions defined by the programmer and called by GoJS:
In lieu of setting HTMLInfo.hide, you can set the HTMLInfo.mainElement property to the primary HTML Element that you are showing/hiding, and HTMLInfo will automatically hide the provided element by calling:
mainElement.style.display = "none";
For tooltips, if a GraphObject.toolTip or Diagram.toolTip is set to an instance of HTMLInfo
, GoJS calls
HTMLInfo.show
in ToolManager.showToolTip. After the tooltip delay, GoJS will call HTMLInfo.hide
in
ToolManager.hideToolTip.
What follows is an example using HTMLInfo.show
and HTMLInfo.hide
, but the HTMLInfo.hide
is simple enough that setting
the HTMLInfo.mainElement
to the tooltip div instead would be sufficient.
function showToolTip(obj, diagram, tool) {
var toolTipDIV = document.getElementById('toolTipDIV');
var pt = diagram.lastInput.viewPoint;
toolTipDIV.style.left = (pt.x + 10) + "px";
toolTipDIV.style.top = (pt.y + 10) + "px";
document.getElementById('toolTipParagraph').textContent = "Tooltip for: " + obj.data.key;
toolTipDIV.style.display = "block";
}
function hideToolTip(diagram, tool) {
var toolTipDIV = document.getElementById('toolTipDIV');
toolTipDIV.style.display = "none";
}
var myToolTip = $(go.HTMLInfo, {
show: showToolTip,
hide: hideToolTip
/*
since hideToolTip is very simple,
we could have set mainElement instead of setting hide:
mainElement: document.getElementById('toolTipDIV')
*/
});
diagram.nodeTemplate =
$(go.Node, "Auto",
{
toolTip: myToolTip
},
$(go.Shape, "RoundedRectangle", { strokeWidth: 0},
new go.Binding("fill", "color")),
$(go.TextBlock,
{ margin: 8 },
new go.Binding("text", "key"))
);
diagram.model = new go.GraphLinksModel(
[
{ key: "Alpha", color: "lightblue" },
{ key: "Beta", color: "orange" },
{ key: "Gamma", color: "lightgreen" },
{ key: "Delta", color: "pink" }
]);
<!-- this must be added as a sibling of the Diagram -->
<div id="toolTipDIV" style="position: absolute; background: white; z-index: 1000; display: none;">
<p id="toolTipParagraph">Tooltip</p>
</div>
For context menus, ContextMenuTool.showContextMenu will call HTMLInfo.show
. ContextMenuTool.hideContextMenu will call
HTMLInfo.hide
.
// Assign an HTMLInfo to the Diagram:
myDiagram.contextMenu = $(go.HTMLInfo, {
show: showContextMenu,
hide: hideContextMenu
});
function showContextMenu(obj, diagram, tool) {
// Show the context menu HTML element:
SomeDOMElement.style.display = "block";
// Also show relevant buttons given the current state
// and the GraphObject obj; if null, the context menu is for the whole Diagram
}
function hideContextMenu() {
SomeDOMElement.style.display = "none";
}
function buttonClick() {
// do some action when a context menu button is clicked
// then:
myDiagram.currentTool.stopTool();
}
For custom text editors, TextEditingTool.doActivate will call HTMLInfo.show
. TextEditingTool.doDeactivate will call
HTMLInfo.hide
.
HTMLInfos used as text editors must also define a HTMLInfo.valueFunction. When TextEditingTool.acceptText is called, GoJS will call
HTMLInfo.valueFunction
and use the return value as the value for the TextEditingTool completion.
The example below constructs an HTMLInfo that uses HTMLInfo.show
and HTMLInfo.hide
to dynamically add, populate, and remove HTML
elements from the page.
// Diagram setup. The HTMLInfo is set at the end of this code block.
diagram.nodeTemplate =
$(go.Node, "Auto",
$(go.Shape, "RoundedRectangle", { strokeWidth: 0},
new go.Binding("fill", "color")),
$(go.TextBlock,
{ editable: true, margin: 8, choices: ['Alpha', 'Beta', 'Gamma', 'Delta'] },
new go.Binding("text"))
);
diagram.model = new go.GraphLinksModel(
[
{ text: "Alpha", color: "lightblue" },
{ text: "Beta", color: "orange" },
{ text: "Gamma", color: "lightgreen" },
{ text: "Delta", color: "pink" }
]);
// Create an HTMLInfo and dynamically create some HTML to show/hide
var customEditor = new go.HTMLInfo();
var customSelectBox = document.createElement("select");
customEditor.show = (textBlock, diagram, tool) => {
if (!(textBlock instanceof go.TextBlock)) return;
// Populate the select box:
customSelectBox.innerHTML = "";
// this sample assumes textBlock.choices is not null
var list = textBlock.choices;
for (let i = 0; i < list.length; i++) {
var op = document.createElement("option");
op.text = list[i];
op.value = list[i];
customSelectBox.add(op, null);
}
// After the list is populated, set the value:
customSelectBox.value = textBlock.text;
// Do a few different things when a user presses a key
customSelectBox.addEventListener("keydown", e => {
if (e.isComposing) return;
var key = e.key;
if (key === "Enter") { // Accept on Enter
tool.acceptText(go.TextEditingAccept.Enter);
return;
} else if (key === "Tab") { // Accept on Tab
tool.acceptText(go.TextEditingAccept.Tab);
e.preventDefault();
return false;
} else if (key === "Escape") { // Cancel on Esc
tool.doCancel();
if (tool.diagram) tool.diagram.focus();
}
}, false);
var loc = textBlock.getDocumentPoint(go.Spot.TopLeft);
var pos = diagram.transformDocToView(loc);
customSelectBox.style.left = pos.x + "px";
customSelectBox.style.top = pos.y + "px";
customSelectBox.style.position = 'absolute';
customSelectBox.style.zIndex = 100; // place it in front of the Diagram
diagram.div.appendChild(customSelectBox);
}
customEditor.hide = (diagram, tool) => {
diagram.div.removeChild(customSelectBox);
}
// This is necessary for HTMLInfo instances that are used as text editors
customEditor.valueFunction = () => customSelectBox.value;
// Set the HTMLInfo:
diagram.toolManager.textEditingTool.defaultTextEditor = customEditor;