Ash Tewari

xaml

Universal Windows Platform Application on Raspberry Pi

tewari

Universal Windows Platform (UWP) provides a common app platform on every device that runs Windows 10. The core APIs in UWP are the same on all Windows devices – including Desktop PC, Mobile Phone, XBox, Hololens, IOT devices and others.  You can target specific device capabilities of a device family with extension SDKs, but you don’t have to do that if you are only using core APIs. Those core APIs include a very impressive set of UI capabilities. What that means is that you can create a UWP application using C# and XAML which will run on an ARM based processor on Raspberry Pi – because Windows 10 IOT Core runs on that. Universal Windows Platform (UWP) has come a long way. I decided to […]

Announcing CodeDemo

tewari

It is a challenge to use code snippets in presentations, demos and live coding sessions. I have struggled with this and seen many speakers jumping through hoops to assimilate code snippets in their demos. I had to create something to ease this pain. Today, I am announcing the general availability of CodeDemo. A tool for instructors, presenters and speakers who create instructional demos, record screen-casts or do live presentations. CodeDemo pastes code snippets into your favorite IDE without getting in your way. I decided not to open-source CodeDemo to challenge myself to an exercise in commercialization. I decided to learn about entrepreneurship, marketing, sales, licensing and other aspects of software commercialization. It has been an MBA’s worth of education so […]

Remove ListBoxItem Highlighting

tewari

A Silverlight/Wpf ListBoxItem is highlighted when selected or when the mouse hovers over it. I need to display a list of items that are not highlighted when selected. This is a common scenario when displaying an inactive list for simply listing out some information. ListBoxItem’s default template can be easily inspected and modified using Expression Blend – Select a ListBoxItem in Objects and Timeline pane, Right click and select Edit template > Edit a Copy. Name you template and save it at the scope of your choice. This will create a copy of the template and allow you to modify it. Switch to the xaml view. Locate the VisualStates of MouseOver, Selected and Focused, and blank them out – The […]

Using Model-View-ViewModel in WPF Applications

tewari

I am presenting at SoCalCodeCamp this weekend (January 30th, 2010) – Advanced WPF – Using Model-View-ViewModel in WPF Applications. Agenda : 1. Roles of the M-V-VM triad 2. Why use M-V-VM ? 3. Characteristics of the ViewModel 4. Build a Sample WPF Application using M-V-VM Resources : MSDN Magazine Article and Sample Application Download Martin Fowler’s description of the ‘Presentation Model ‘ Jeremy Miller’s ‘Build Your Own CAB’ series

Dial Gauge is a ProgressBar

tewari

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 . 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 […]

Using Custom Converter in XAML

tewari

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, […]