2014 ~ My Visual C#

You might have a code that needs to download data from internet or access to a file on your local drive.. These kind of processes extends the response time of your software and you may want to take caution for that. Asynchronous Programming is the methodology to set the run time more responsive.

An example code is shown below (source: http://msdn.microsoft.com/en-us/library/system.io.stream(v=vs.110).aspx) Here the method is defined as async because loading files on local drive may take time.

private async void Button_Click(object sender, RoutedEventArgs e)
        {
            string StartDirectory = @"c:\Users\exampleuser\start";
            string EndDirectory = @"c:\Users\exampleuser\end";

            foreach (string filename in Directory.EnumerateFiles(StartDirectory))
            {
                using (FileStream SourceStream = File.Open(filename, FileMode.Open))
                {
                    using (FileStream DestinationStream = File.Create(EndDirectory + filename.Substring(filename.LastIndexOf('\\'))))
                    {
                        await SourceStream.CopyToAsync(DestinationStream);
                    }
                }
            }
        }

Good resources on MSDN:

Asynchronous Programming with Async and Await (C# and Visual Basic)

http://msdn.microsoft.com/en-us/library/hh191443.aspx

Calling Synchronous Methods Asynchronously

http://msdn.microsoft.com/en-us/library/2e08f6yc(v=vs.110).aspx

async (C# Reference)

http://msdn.microsoft.com/en-us/library/hh156513.aspx

Lets’ say I want to add 25 buttons on my app. And I also want each button to have a large width so it’s as large as the screen and I also want each button to have a sizable thickness. Obviosly, under these circumstances my buttons won’t fit to my screen. So, how can such an app be possible? In this example we will investigate that but first, let’s picture what I want from my app

This is quite easy and it doesn't require any binding. We need to create a ListBox and add all the buttons under this ListBox and it’s done. I also added a button to make the ListBox visible / invisible. Here’s the XAML needed:

<phone:PhoneApplicationPage

x:Class="ListofButtons.MainPage"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"

xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"

xmlns:d="http://schemas.microsoft.com/expression/blend/2008"

xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

mc:Ignorable="d"

FontFamily="{StaticResource PhoneFontFamilyNormal}"

FontSize="{StaticResource PhoneFontSizeNormal}"

Foreground="{StaticResource PhoneForegroundBrush}"

SupportedOrientations="Portrait" Orientation="Portrait"

shell:SystemTray.IsVisible="True">

<Grid.RowDefinitions>

</Grid.RowDefinitions>

</StackPanel>

</ListBox>

</Grid>

<!--Uncomment to see an alignment grid to help ensure your controls are

aligned on common boundaries. The image has a top margin of -32px to

account for the System Tray. Set this to 0 (or remove the margin altogether)

if the System Tray is hidden.

Before shipping remove this XAML and the image itself.-->

</Grid>

</phone:PhoneApplicationPage>

Here’s the C# section. This section pretty much only controls the ListBox.

public partial class MainPage : PhoneApplicationPage

{

static int _buttonListVisiCounter = 0;

// Constructor

public MainPage()

{

InitializeComponent();

// Sample code to localize the ApplicationBar

//BuildLocalizedApplicationBar();

}

private void Button_Click(object sender, RoutedEventArgs e)

{

if (_buttonListVisiCounter % 2 == 0)

{

ButtonList.Visibility = System.Windows.Visibility.Collapsed;

}

else

{

ButtonList.Visibility = System.Windows.Visibility.Visible;

}

_buttonListVisiCounter++;

}

And here’s the screen output

My Visual C#

This blog is about learning visual c#, XAML and .NET environment to develop for windows OS.

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Wednesday, January 29, 2014

What is Asynchronous Programming?

Tuesday, January 28, 2014

Quality C# (C sharp) Code Examples

Monday, January 27, 2014

Windows phone emulator not connected to internet

Sunday, January 26, 2014

Using ListBoxes with Buttons and Adding Many Buttons

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