Using NHibernate With SQLite in DbUpdater

DbUpdater (version 1.3 onwards) can be used with sqlite3.

Review the files included in DbUpdater-sqlite3.zip

1. DbUpdater.exe.config must be modified. Note changes to the following keys – exe-file, exe-args, dialect, driver_class, connetion_string.
2. SchemaVersion.hbm.xml must be modified. The ‘class’ attributes value for the ‘generator’ of ‘id’ must be changed to ‘identity’. No other changes are needed here.
3. \SqlScripts\schema-version-table.sql is modified. Note that the datatypes of all columns are changed to TEXT, except for SchemaChangeId, which is changed to integer primary key. integer primary key is used for auto-incremented columns in sqlite.
4. \SqlScripts\baseline.sql is modified. Note the use of current_timestamp function. The actual sql syntax in this file must conform to sqlite dialect.
5. All other .sql scripts in \SqlScripts directory are also modified to conform to sqlite dialect.

The following files are expected to be in DbUpdater.exe directory (as configured in the DbUpdater.exe.config file) –

1. sqlite3.exe : download.
2. System.Data.SQLite.dll : download.
3. createdb.bat file : This file is included. This batch script will call sqlite3.exe to execute sql queries.

Another very useful tool for working with sqlite database files is SQLite Database Browzer.

Dial Gauge is a ProgressBar

I am not just being philosophical here. In WPF, ControlTemplates allow you to transform a control’s appearance. This is not the same as applying stylesheets. This is an entirely new level of customization. What you see in the screenshot below looks like a Dial but is actually a simple ProgressBar control wearing a “Dial” template. The Dial template was created using Microsoft Expression Blend .

dial-is-a-progressbar.PNG

Include the ControlTemplate as a Window.Resource and then assign it to ProgressBar element’s Template attribute :

Of course that is not all. The ControlTemplate must define some named elements of FrameworkElement type. Charles Petzold has explained it in detail : MSDN Magazine Article. So, I will not repeat it here.

The sample code can be downloaded here : DialTest.zip
License : Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.

PostSharp with SharpDevelop

SharpDevelop3.0 uses MSBuild. Including PostSharp in your build process is transparent if you are doing a global install using PostSharp installer. If you are doing a per-project installation using “Binary – No Installer” download, you will need to import the PostSharp targets into your .csproj file –


    True

C:\code\PostSharp-1.0.8.316-Binary\

For more details, read the install instructions included in the PostSharp download and under-the-hood-of-msbuild-integration.

To use local PostSharp binaries (relative to your project) , modify your .csproj file as follows –

  
    True
    $(MSBuildProjectDirectory)\PostSharp\

$(MSBuildProjectDirectory) is the directory containing your .csproj file.
\PostSharp\ is the directory containing local PostSharp binaries.

2. You will need to exclude the Aspect class itself from being woven.

If you are following the getting-started sample, see the following example:

[Serializable]
[Trace( null, AttributeExclude = true )]
public sealed class TraceAttribute : OnMethodBoundaryAspect
{

3. Compile your project.

Using Custom Converter in XAML

In my previous post : WPF-LINQ To SQL Sample, I had to resort to modifying .dbml file to get the images stored as varbinary into the WPF ListView control. I had to change the Type of image fields to System.Byte[], instead of using System.Data.Linq.Binary. A better way to do this is to use a custom converter. WPF allows you to specify custom converter as part of the Binding in .xaml, like this –

<Image Grid.Row="2"
Source="{Binding Path=ThumbNailPhoto ,
Converter={StaticResource imageConverter}}"></Image>

The custom converter is declared in the same .xaml file as a resource –

<Window.Resources>
<local:ImageDataConverter x:Key="imageConverter" />
</Window.Resources>

ImageDataConverter is implemented in .xaml.cs file –

public class ImageDataConverter : IValueConverter
{
   public object Convert(object value, Type targetType, object parameter,
   System.Globalization.CultureInfo culture)
   {
      byte[] image = ((System.Data.Linq.Binary)value).ToArray();
      return image;
   }

   public object ConvertBack(object value, Type targetType, object parameter,
   System.Globalization.CultureInfo culture)
   {
      throw new NotSupportedException();
   }
}

The updated sample code can be downloaded here : WPF-LINQ to SQL Sample
License : Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.