WPF Images only update after timespan is done

user_10388208 0
Viewed 80

My program need to show some text to show for x amount of seconds. The problem is that the text only appears after the timespan check is done. Here is my code:

        // Clicks button to show texts

        //Displays text wanted basicly Text.Visibility =Visibility.Visible;
        DisplayWords();

        //Waits x amount of seconds before hidden them
        int nbOfSecondsToWait = Convert.ToInt32(SecondAffichage.Value);
        DateTime timeNow;
        timeNow = DateTime.Now;
        TimeSpan timePassed = (DateTime.Now - timeNow);
        TimeSpan timePassedWanted = new TimeSpan(0, 0, nbOfSecondsToWait);
        while (timePassed < timePassedWanted)
        {
            timePassed = DateTime.Now - timeNow;

        }

        //Hide texts

My text only appears after the timespan check and then get hidden immediately

timespan wpf c#
2 Answers

Use Task.Delay in an async method:

public async Task ShowText()
{
    DisplayWords();

    int nbOfSecondsToWait = Convert.ToInt32(SecondAffichage.Value);

    await Task.Delay(TimeSpan.FromSeconds(nbOfSecondsToWait));

    //Hide texts
}
user_11362110

It's not displaying because your code is in a hard loop, and you are not giving the UI time to handle the changes made in your DisplayWords() method. If you put an Application.DoEvents(); right after DisplayWords();, it should allow the OS time to update the UI.

You could also do this instead:

// Clicks button to show texts

//Displays text wanted basicly Text.Visibility =Visibility.Visible;
DisplayWords();
Application.DoEvents();

//Waits x amount of seconds before hidden them
System.Threading.Thread.Sleep(nbOfSecondsToWait * 1000);

//Hide texts
user_20724720
Related