> For the complete documentation index, see [llms.txt](https://sway-technologies.gitbook.io/sway-charts-pro-scripts-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sway-technologies.gitbook.io/sway-charts-pro-scripts-documentation/sway-charts-pro-user-defined-indicators/adding-html-to-the-chart/7.1-adding-html.md).
# 7.1 Adding HTML
You add HTML to the chart using UDI.createHTML(). For example:
```
UDI.createHTML({
foreground: true,
html: "Hello!"
});
```
A second call to UDI.createHTML() replaces the previous HTML with the new HTML. You can remove your HTML from the chart using UDI.removeHTML().
The options which are passed to UDI.createHTML() can contain the following properties. You must provide either the html or url.
| Property | Description |
| ---------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| html | Text of the HTML to add; a complete document with \ and \ tags |
| url | URL of a web page to load. Standard browser security requires that this is hosted at a secure https\:// address. |
| foreground | Controls whether the HTML is displayed in the background, behind the indicator drawing, or in the foreground. If your HTML includes elements for the user to interact with, such as buttons or fields, then you must set foreground:true. |
| style | Lets you set CSS style options on the iframe container, particularly the position. For example:
style: {opacity: 0.5, pointer-events: none}
You cannot set the position, which is always absolute (within its container). You cannot set zIndex, which is instead controlled by the foreground option.
|
---
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