更改按钮的颜色和文本一段时间

Question

I have to change the text and color of a button while the Click Event has occured, but just for a few seconds, then the old values for text and color should appear.

How could this work? Maybe with a async task, which reset the values after the time is elapsed?

The problem is I recognized that the color and the text will be updated only after the click event method has finished.

Answer 1

I am currently doing lot of research on async and await and currently somewhat addicted to it. So I could not stop myself from answering this one.

Check out a small sample, below :

XAML Code:

<Grid >
    <Button x:Name="Button1" Content="Click Me" Width="88" Height="44" Click="Button1_Click"/>
</Grid>

Code Behind :

private async void Button1_Click(object sender, RoutedEventArgs e)
{
    Button1.Background = Brushes.Red;
    Button1.Content = "Clicked State";
    await Task.Delay(8000);
    Button1.Background = Brushes.Transparent;
    Button1.Content = "Click Me";
}

Now let me explain what's happening here :

1. When the button is clicked, it will enter the async button clicked event handler Button1_Click.

2. The button color is changed to red and content changed to "Clicked State".

3. Now we can call await Task.Delay(8000), ie the execution of the function is now waiting for the task to complete, which is delayed by 8 seconds. The execution returns to the main UI thread and your UI is still responsive.

4. After 8 seconds is complete, a free thread from the thread pool will again start executing the rest of the method, after await.

5. The button is changed to default background color and content is changed to "Click Me" which was the default content.

Hope this helps.