Content settings for the webview.
HTML contents of the webview.
This should be a complete, valid html document. Changing this property causes the webview to be reloaded.
Webviews are sandboxed from normal extension process, so all communication with the webview must use
message passing. To send a message from the extension to the webview, use postMessage.
To send message from the webview back to an extension, use the acquireVsCodeApi function inside the webview
to get a handle to the editor's api and then call .postMessage():
<script>
const vscode = acquireVsCodeApi(); // acquireVsCodeApi can only be invoked once
vscode.postMessage({ message: 'hello!' });
</script>
To load a resources from the workspace inside a webview, use the asWebviewUri method
and ensure the resource's directory is listed in WebviewOptions.localResourceRoots.
Keep in mind that even though webviews are sandboxed, they still allow running scripts and loading arbitrary content, so extensions must follow all standard web security best practices when working with webviews. This includes properly sanitizing all untrusted input (including content from the workspace) and setting a content security policy.
Fired when the webview content posts a message.
Webview content can post strings or json serializable objects back to an extension. They cannot
post Blob, File, ImageData and other DOM specific objects since the extension that receives the
message does not run in a browser environment.
Content security policy source for webview resources.
This is the origin that should be used in a content security policy rule:
`img-src https: ${webview.cspSource} ...;`
Post a message to the webview content.
Messages are only delivered if the webview is live (either visible or in the
background with retainContextWhenHidden).
Body of the message. This must be a string or other json serializable object.
For older versions of vscode, if an ArrayBuffer is included in message,
it will not be serialized properly and will not be received by the webview.
Similarly any TypedArrays, such as a Uint8Array, will be very inefficiently
serialized and will also not be recreated as a typed array inside the webview.
However if your extension targets vscode 1.57+ in the engines field of its
package.json, any ArrayBuffer values that appear in message will be more
efficiently transferred to the webview and will also be correctly recreated inside
of the webview.
A promise that resolves when the message is posted to a webview or when it is dropped because the message was not deliverable.
Returns true if the message was posted to the webview. Messages can only be posted to
live webviews (i.e. either visible webviews or hidden webviews that set retainContextWhenHidden).
A response of true does not mean that the message was actually received by the webview.
For example, no message listeners may be have been hooked up inside the webview or the webview may
have been destroyed after the message was posted but before it was received.
If you want confirm that a message as actually received, you can try having your webview posting a confirmation message back to your extension.
Convert a uri for the local file system to one that can be used inside webviews.
Webviews cannot directly load resources from the workspace or local file system using file: uris. The
asWebviewUri function takes a local file: uri and converts it into a uri that can be used inside of
a webview to load the same resource:
webview.html = `<img src="${webview.asWebviewUri(vscode.Uri.file('/Users/codey/workspace/cat.gif'))}">`
Displays html content, similarly to an iframe.