I created a project by using Master Detail project template; and add following code in order to simulate the scenario: to change some images of the list items using timer.

IViewService viewService = this.GetService<IViewService>();
            
if (viewService != null)
{
    viewService.RunOnBackgroundThread(() =>
    {
        Item firstItem = this.Items.FirstOrDefault();
        firstItem.ThumbnailImage = null;
    }, 5000);
}

The above code will set the ThumbnailImage to null for the first item of ListView after 5 second.

In order to update the image, simply call OnDataChanged(object) method after set the changes.

if (viewService != null)
{
    viewService.RunOnBackgroundThread(() =>
    {
        Item firstItem = this.Items.FirstOrDefault();
        firstItem.ThumbnailImage = null;
        this.OnDataChanged(firstItem);
    }, 
}

Note: the above changes are made in the constructor of ItemListViewModel of Core project in the project created by using Master Detail project template.

Hello Yudi,

I wonder how you test these samples. I did the same thing you described in your last post. I tested on two devices (Samsung Galaxy Phone and Tablet). On each device I get the same results. Start the sample app, wait for 5, 10, 15 seconds and nothing happens. No image changes in the list. Then I rotated the devices from portrait to landscape. With the rotation there seems to be a refresh and there you go. The image changes.

Similar results on iOS.

Please, check this again.

Thanks,

Thomas

Any news here?

Thanks,

Thomas

Sorry for the delay in sending this.

I uploaded my sample project in OneDrive. Please have the sample downloaded in here; and have it evaluated on your end and let us know whether it helps or not. For your information, I'm using Crosslight 2 Update 4.

Hello Yudi,

tested on Android device. Works.

Thanks,

Thomas

Glad to hear that the sample helps.

Should you need further assistance or run into any problems regarding our controls, feel free to post it into our forum. We would be happy to assist you again.