So just have a bool

isLoaded

or something like that that gets set to true in the promise coming back from the API call

Also what does tryExcuteAndNotify() helping me to do? Ie what do I get for free and not have to write myself ?!

Also is the pattern for loading things to have a loader inside a uui-box if the data is to be put inside it once loaded/fetched. Or do I not show the uui-box at all and just have the loader and then show the box and data together once ready

Also you have three loaders, is there one that should be used more than another and if I go for the circle of these dots. Should it be placed centered in the uui-box ? I know I can do whatever I want here, but be good to try and follow similar UI patterns you will be using.

And I am clearly doing something wrong, my API call gets the data (can see it in network request) but the loader never goes away and show me something from my API data 🤔

private async _getThing(key: string) : Promise<ISearchResult | undefined> {
    const { data, error } = await tryExecuteAndNotify(this, ThingResource.getThing({key: key}))
    if (error){
        console.error(error);
        return undefined;
    }
    
    this._hasLoadedRecord = true;
    return data;
}

render() {
        return html`
            <umb-body-layout headline="Thingy">
                <uui-box>
                    ${ this._hasLoadedRecord ? html `<h2>${this._thingItem?.id}</h2>` : html `<uui-loader></uui-loader>` }
                </uui-box>
                
                <uui-box>
                    <h2>Return Value</h2>
                </uui-box>

                <div slot="actions">
                    <uui-button id="close" label="Close" @click="${this.handleClose}">Close</uui-button>
                </div>
            </umb-body-layout>
        `;
    }

Arggh OK forgot to decorate my property with

@property()

to make it reactive 🙈

You sick and tired of my questions yet @Niels Lyngsø 😂

but I can tell on the spectrum of UI / UX, we are not spending too much time yet. We are focusing on the Core APis. so please keep it on that topic. 🙂 the other idea/feedback are good, but save them 🙂