Vscode extension, setting window.activeTextEditor

Question

How can I use the vscode extension api to set the activeTextEditor?

The reason I need this is because my extension depends on an external call to extension B, and extension B does not take an argument for editor. It just looks at vscode.window.activeTextEditor.

My extension is a webview which calls Extension B when something is clicked on the webview. At that moment in time, the 'active tab' is the webview, which is not activeTextEditor that I want.

I want to do something like

vscode.window.activeTextEditor = editor

at the start of my click handler, but this doesn't work because activeTextEditor is not a setter.

I tried making a fake edit on the editor in question:

function changeFocus(editor: vscode.TextEditor) {
  return editor.edit((editBuilder) => {
    const pos = new vscode.Position(0, 0);
    const nxt = new vscode.Position(0, 1);
    editBuilder.insert(pos, "\\");
    editBuilder.delete(new vscode.Range(pos, nxt));
  });
}

but this does not change vscode.window.activeTextEditor variable (it is still undefined).

Answer 1

If I understand correctly, this opens and focuses another file:

const currentWorkSpace = await vscode.workspace.getWorkspaceFolder(vscode.window.activeTextEditor.document.uri);

vscode.window.showTextDocument(vscode.Uri.joinPath(currentWorkSpace.uri, 'search/oldSearch.js'), { preview: false });

It is focussed and writable at its previously saved cursor position.

showTextDocument() has two other forms, one of which can take a TextDocument as the file to be opened, rather than a Uri.

There is also openTextDocument() which can create a new untitled file if you wish.

If the file is already open, this code will still serve to focus it and thus you have your activeTextEditor.