Silverlight

Silverlight 4 Clock

Silverlight
Silverlight
I was trying to get my Development Environment up & running the other day with Silverlight 4. It turns out that the Silverlight debug runtime isn’t actually part of the standard client, or the Silverlight 4 Tools for Visual Studio.

Thanks to this thread I discovered

The “Silverlight managed debugging package” is part of the developer runtime, not the SDK or Tools. Make sure you have the latest version of the developer runtime installed (available at http://go.microsoft.com/fwlink/?LinkID=188039

On the plus side I did throw together this nice pretty clock just to test everything out.
There’s probably a dozen ways to break this, but it covers the basic for autosizing the grid, limiting the dimensiosn with min height & max height sections, drawing lines & drawing ellipses & a small bit of math.



XAML

<UserControl x:Class="SlvrClock.Lib.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="400" MinHeight="100" MinWidth="100">
    <Grid x:Name="LayoutRoot" Background="Black">
        <Line x:Name="lh" Stroke="Green" StrokeThickness="15" StrokeStartLineCap="Round" StrokeEndLineCap="Triangle" />
        <Line x:Name="lm" Stroke="Blue" StrokeThickness="10" StrokeStartLineCap="Round" StrokeEndLineCap="Triangle" />
        <Line x:Name="ls" Stroke="Red" StrokeThickness="5" StrokeStartLineCap="Round" StrokeEndLineCap="Triangle" />
        <Ellipse x:Name="el" Stroke="Yellow" StrokeThickness="5" />
    </Grid>
</UserControl>

C#

public partial class MainPage : UserControl
{
    private Storyboard timer = new Storyboard(); //timer
    private const double radian = Math.PI / 180; //radian
    private bool started = false;
    private double MaxHandLength { get; set; } //shorter length of width:height
    private Point CenterPoint { get; set; }
        
    public MainPage()
    {
        InitializeComponent();
        timer.Duration = TimeSpan.FromMilliseconds(50);
        timer.Completed += new EventHandler(Timer_Completed);
        timer.Begin();
    }

    protected void Timer_Completed(object sender, EventArgs e)
    {
        double aw2 = LayoutRoot.ActualWidth / 2, ah2 = LayoutRoot.ActualHeight / 2;
        if (!started || CenterPoint.X != aw2 || CenterPoint.Y != ah2)
        {
            //Reset the centerpoint & ratios on startup or if the window resizes.
            CenterPoint = new Point(aw2, ah2);
            MaxHandLength = Math.Min(CenterPoint.X, CenterPoint.Y);
            el.Height = el.Width = ((MaxHandLength - 10) * 2);
            lh.X1 = lm.X1 = ls.X1 = CenterPoint.X;
            lh.Y1 = lm.Y1 = ls.Y1 = CenterPoint.Y;
            started = true;
        }
        var now = System.DateTime.Now;
        //line hour - apply partial split for smoother transition and update more than onces per second.
        ChangeHand(lh, MaxHandLength - 80, 30 * (now.Hour + ((double)now.Minute) / 60));
        //line minute
        ChangeHand(lm, MaxHandLength - 60, 6 * (now.Minute + ((double)now.Second) / 60));
        //line second
        ChangeHand(ls, MaxHandLength - 40, 6 * (now.Second + ((double)now.Millisecond) / 1000));
        timer.Begin();
    }

    protected void ChangeHand(Line l, double r, double a) {
        //Calculate the point on the circumference based on Center, Radius & Angle.
        var i = a * radian;
        l.X2 = CenterPoint.X + r * Math.Sin(i);
        l.Y2 = CenterPoint.Y + r * -Math.Cos(i);
    }
}
Config Fun

InstallUtil, Windows Services & ProjectInstallers with App.Config Settings

Config Fun
Config Fun
We had a situation in work where we needed to make service installation a more configurable process.

So a very simple example, In order to install a .NET Windows Service we need to provide it with a username & password that the services will run as. We can either provide that information at installation time, or through the following properties in the ProjectInstaller.cs file for your service.

However in an environment where multiple developers are working on a service, particularly a service that requires elevated privileges and needs to run as a specific account, this can be a royal pain.

Read More “InstallUtil, Windows Services & ProjectInstallers with App.Config Settings”

Bad Luck

Bad Timing & The Mysterious AWS XML Exception

Bad Luck
Bad Luck
Server Time Mis-configured, Amazon Web Services S3 .NET SDK has a bug in it, Vague XMLExceptions that don’t make sense.

Sometimes karma is just going to get you. There’s no point fighting it. A series of events & issues just come together in cosmic bliss guaranteed to completely wreck your weekend.

We rolled out some new code for a new client last week. One of the “big stories” for both us and the client was a migration away from in-house content storage to a cloud based solution. We had opted to use Amazon S3 for the file storage part and after ~6 weeks of project development, rigourous QA & Regression testing, and a bit of a stressful production release we were good to go. Our Biz/Mkt team had seen it and they were happy. Last minute checks of the production service were done, all looked good, and home we went.

Read More “Bad Timing & The Mysterious AWS XML Exception”

Converting to Base62 & URL Shortening

Generic Marketeer: “Why do we need to shorten the URLs, people just click on them. It’s not like they have to memorize them; call them out to their friends”

Me: “Eh… no you’re right, but I do need to jam them into a SMS WAPPush along with some descriptive text, so I don’t have much room to play with”

Generic Marketeer: “Fine, as long as it doesn’t impact the project deadline”

Cue, my good self scurying away to find a way to bang out a private URL Shortening service in as short a time as possible. The URL Storage itself was a piece of pie. But I did stumble across some nice code while I was at it. I started out with a int-to-base64 implemenation. but the `+` & `/` characters are fugly to deal with in URLs. I tried a Hex version as well but it just didn’t look bit-ly-y enough. Enter the baseAnything encoder. Just point it at any character set and it will encode/decode to that number of chars.

The following extension methods convert longs to strings, and vice-versa

public static string ToBase(this long input, string baseChars)
{
    string r = string.Empty;
    int targetBase = baseChars.Length;
    do
    {
        r = string.Format("{0}{1}",
            baseChars[(int)(input % targetBase)],
            r);
        input /= targetBase;
    } while (input > 0);

    return r;
}

public static long FromBase(this string input, string baseChars)
{
    int srcBase = baseChars.Length;
    long id = 0;
    string r = input.Reverse();

    for (int i = 0; i < r.Length; i++)
    {
        int charIndex = baseChars.IndexOf(r[i]);
        id += charIndex * (long)Math.Pow(srcBase, i);
    }

    return id;
}

I’ve been using it against the first character set below, but you could easily tweak it to remove any “confusing” characters, or any set for that matter.

private static string ALPHANUMERIC =
    "0123456789" +
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ" +
    "abcdefghijklmnopqrstuvwxyz";

//Remove 0oO1iIl - Base52
private static string ALPHANUMERIC_ALT =
    "23456789" +
    "ABCDEFGHJKLMNPRSTUVWXYZ" +
    "abcdefghjkmnpqrstuvwxyz";
}

Now all I have to do is go write a Math Engine for it 😉