Chpater1:Introduction to WPF

• Window Presentation Foundation (WPF) is the next promotion presentation system for building windows Client application.

• The core of WPF is a resolution-independent and vector –based rendering engine that is built to task the advantage of modern graphics hardware.

• WPF inherits the core with the wide-ranging set of application –development features.

(.Net Framework 4.0)

1.1 Programming with WPFLocated in System.Windows name space, WPF is

presented as subset of .Net Framwork types.It is familiar if you have experiences building

application with .Net Framework: instantiate classes set properties ,call methods, and handle events in your favorite language such as C# or VB.Net

WPF incorporates additional programming construct that improve properties and events : dependency properties and routed events for supporting WPF abilities and simplifying programming experiences

1.2 Markup and Code Behind

One of additional enhancements for Window Client application development is facility in development using both markup and code-behind. You generally use Extensible Application Markup Language (XAML) markup to implement the appearance of an application while using programming language (Code-behind) to implement its actions.

The advantages of separating appearance and

behavior :

Reducing the cost of development and

maintenance

Making more efficient in development

Capability of using multiple design tools to

implement and share XAML markup and

target the requirements of application

development contributor

Simplification of globalization and

localization for WPF application

MarkupXAML is XML based that is used to implement appearance of application declaratively. It is usually used to create windows, dialog boxes, pages, and user controls and to fill them with controls, shape and graphics.Here is an example of using XAML to implement appearance that has window and single button:<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" Title="Window with Button" Width="250" Height="100"> <!-- Add button to window --> <Button Name="button">Click Me!</Button> </Window>

Code-BehindThe main performance of an application is to

realize the functionality that respond to user interactions incorporate handling events (for example clinking menu) and calling business logic and data access logic in response. In WPF, this behavior is generally implemented in code that is associated with markup.XAML

<Windowxmlns=“http://schemas.microsoft.com/

winfx/2006/xaml/presentation”

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

xaml”x:Class=“SDKSample.AWindow”Title=“Window with Button”Width=“250” Height=“100” ><!– Add button to window--><Button Name=“button” Click=“button_Click”> Click Me!</Button></Window>

using System.Windows;namespace SDKSample{

public partial class Awindow:Window{public AWindow(){InitializeComponent();}void button_Click(object sender, RoutedEventArgs e){MessageBox.Show(“Hello, WPF”);}}

}

ApplicationBeside the foundation of the WPF application

development, WPF has broad features for generating user experiences with rich content. In order to reach this WPF provide types and services that are collectively known as the application model. It support both standalone and browser-hosted applications.

Standalone Application: you can use window class to create windows and dialog box that are access from menu bar and access bar.

Browser-Hosted Application: or XAML browser applications (XBAPs), you can create page(s) and page function( Pagefunction-T) that you can navigate between using hyperlinks(Hyperlink classes).

WPF offers the two following option for alternative navigation hosts: Frame (Hosting island of navigable content in either pages or windows) NavigationWindow ( Hosting navigable content in an entire window)

The Application Class: used to encapsulate some services( shared properties and resources, startup and lifetime management…)<Applicationxmlns:http:”//shemas.microsoft.com/winfx/2006/ xaml/presentation“ StartupUri=“Mainwindow.xaml”/>

Security: Since hosting in browser security is important. Partial security sandbox is used to enforce restriction.

ControlsControls was built by user experience

delivered by application model. In WPF control is a wide-ranging term applied to category of WPF classes hosted in both pages and window, have UI and implement some behavior.

Some built-in WPF controls are: Button ( Button & RepeatButton) DataDisplay ( Datagrid, ListView and TreeView) etc.

Input and CommandingTo isolate user input actions from the code

responding to those actions WPF provides a command system.

Layout: Key requirement of any layout is to manage to change in window size and display settings. Instead of using your code , you can use WPF first class, extensible layout system.

In addition to basis of relative positioning , layout system manages the negotiation between control to determine the layout.

Layout system is exposed to child control through base WPF classes. For common layout such as grids, stacking, and docking.<Windowxmlns=“http://schemas.microsoft.com/winfx/2006/ xaml/presentation”xmlns:x=“http://schemas.microsoft.com/winfx/2006/ xaml”x:Class=“SDKSample.LayoutWindow”Title=“Layout with the DockPanel” Height=“143” Width=“319”>

<DockPanel><Textbox DockPanel.Dock=“Top”> Dock=“Top” </Textbox><Textbox DockPanel.Dock=“Bottom”>Dock=“Bottom”

</Textbox><Textbox DockPanel.Dock=“Left”> Dock=“Left”</Textbox><Textbox Background=“White”> This Textbox “fills” the remaining space .</Textbox>

</DockPanel>

Data BindingBecause viewing and editing data are the

feature of most applications, WPF already provided for by many technologies such as Microsoft SQL Server, ADO.Net.

Two things that WPF involve are :1. Copying the data from managed object into control2.Ensuring changes related to using control are copied back to the managed object.

The core unit of data binding engine is the Binding class

GraphicsThe following benefits which introduced by

WPF extensively, scalablely and flexibly :Resolution-independent and device-

independent graphicsImproved PrecisionAdvanced Graphics and Animation SupportHardware accelaration

<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="SDKSample.EllipseEventHandlingWindow" Title="Click the Ellipse"> <Ellipse Name="clickableEllipse" Fill="Blue" MouseUp="clickableEllipse_MouseUp" /> </Window>

C# Codeusing System.Windows; // Window, MessageBox using System.Windows.Input; //

MouseButtonEventHandler namespace SDKSample { public partial class EllipseEventHandlingWindow :

Window {

public EllipseEventHandlingWindow() { InitializeComponent(); } void clickableEllipse_MouseUp(object

sender, MouseButtonEventArgs e) { // Display a message

MessageBox.Show("You clicked the ellipse!");

} } }

AnimationAnimation support allow developers to make

controls grow, shake , spin, and fade. You can animate most WPF classes even custom classes.

MediaAudiovisual media is the way of demonstrating

rich content. WPF presents special support for images video and audio.

Images popular for most application and WPF provides several methods to use them

Video and Audio: by using the MediaElement which is capable of playing both audio and video flexibly.

XAML<MediaElement

Name=“myMediaElement”Source=“media/wpf.wmv”LoadedBehavior=“Manual”Width=“350” Height=“250”/>

Text and TypographyWPF offers the following feature in order to

assist high quality text rendering:OpenType font supportClearType enhancementHigh performance that take advantages of

hardware speeding upIntegration of text with media, graphics, and

animationInternational font support and fallback

mechanisms.

DocumentWPF has native support for working with three

types of documents, fixed documents and XML Paper Specification (XPS) documents. Flow documents are designed to optimize viewing

and readability by dynamically adjusting and reflowing content when window size and display setting change.

Fixed Documents are intended for application that require a precise “what you see is what you get” presentation respecting to the printing.

XPS Documents are open, cross-platform document format that is designed to facilitate the creation, sharing, printing, and archiving of paginated document

DocumentWPF has native support for three types

documents: flow documents, fixed documents and XML paper specification(XPS) documents. WPF also provides another services.

Flow documents design to optimize viewing and readability by dynamically adjusting and reflowing content when window size and display setting change.

Fixed document : “What You See is What You Get” , maintain the precise agreement of their content in device-independent manner.

XPL docs built on WPF’s fixed document and described with an XML based schema.

Annotations in WPF , an annotation system provided to support sticky note and highlights. They can be applied to document hosted in document viewer .

Packaging : System.IO.Packaging APIs allow application to organize data content and resource into single portable, easy to distribute and easy to access ZIP documents.

Printing : WPF support many enhanced print system control such as real-time installation, Dynamic discovery…etc

Customizing WPF applicationContent Model: the type and number of items

can constitute the content of a control is referred to as the control ‘s content model.

Trigger : XAML use it to implement application behavior

Control Template : You can use it to change the appearance of the Control’s UI without affecting it content and behavior.

Data Template: let you specify appearance of control’s content

Style: enable developer and designer to standardize on particular appearance on their application. Style element is foundation of WPF’s strong type model.

Resources: WPF support for UI resources to encapsulate these resources in a single location for reuse.

Themes and Skin: WPF does not integrate directly with Window themes. Because WPF’s appearance defined by template it include one template for each of the well-known Window-Themes.

Both themes and skin in WPF are defined using resource dictionary.

Custom Controls: because the existing WPF control do not meet the requirement you can three WPF’s model to create a new control.1. User Control Model: derived from

UserControl 2. Control Model: derived from Control3. Framework Element Model: derived from

FrameworkElement

WPF Best PracticesWith any development platform, WPF can be

used in a variety ways to achieve the desired outcome. It also required user’s experience and meet the demand of the audience in general.