v2.5
Wisej.Web
Wisej.Web.VisualBasic
Wisej.Core
Wisej.Base
System
Application
Wisej.Web.Application
Namespace: Wisej.Web
Assembly: Wisej.Framework (2.0.0.0)
Represent a Wisej application session. Provides methods and events to manage the application in the context of the current session.
C#
VB.NET
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public class Application : IWisejComponent, IDisposable, IWisejSynchronized
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Public Class Application
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Inherits IWisejComponent
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Implements IDisposable, IWisejSynchronized
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This class provides several static methods, properties and events that allow the application to manage all sorts of features related to the current session:
- Save and retrieve session variable.Use Session to store and retrieve session variable. The property is a dynamic object and a Dictionary, therefore you can access its properties directly or through the indexer.
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Application.Session.myValue = 12;
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Application.Session["myValue"] = 12;
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- Manage cookies.
- Read server variables.Use ServerVariables to retrieve all the data made available by the server. Some of the variables in the collection are also available directly: ServerPort, ServerName, UserAgent, etc.
- Read the application's URL.
- Read the applications's system information.
- Listen to the application's global events.See SessionTimeout , BeginRequest, ApplicationStart, ApplicationExitApplicationRefresh, BrowserSizeChangedResponsiveProfileChanged, CultureChanged, and many more.
- Manage all live components in the session.Through the Application class you can find, iterate, inspect all live components of any type. See OpenForms for all the currently created (visible or invisible) instances of Form. OpenPages returns all the created Page objects. FindComponent and FindComponents provide an easy way to find any component in the session or to iterate the list of components that match a custom expression.
- Start background tasks in context.StartTask provides a powerful way to start a background task on the server that can keep interacting with the client browser while running independently.
- Manage the application's theme.Use LoadTheme to load a Wisej theme into the application. Or use the Theme object to read all sorts of information from the current ClientTheme.
- Terminate the application without waiting for the session to timeout. Use Exit to terminate the current session and free all the related memory.There is a lot more exposed by the Application class. You can inspect all the properties and methods in Visual Studio through IntelliSense or online at docs.
Properties
ActiveProfile
This is the profile that best matches the current browser on the client. It is updated automatically on every request.
Browser
ClientFingerprint
The client fingerprint is generated by hashing all the available information returned by the browser (OS, user agent, version, etc.) and it's not guaranteed to be unique.
ClientId
Clients
CommonAppDataPath
CommonAppDataRegistry
CompanyName
String: Returns the company name associated with the application stored in the AssemblyCompanyAttribute.
Configuration
Cookies
Current
IWisejComponent: Returns the application component instance that an application can store and use later to restore the context when updating client widgets during an out-of-bound call using Update
Threads that are not started using StartTask don't have any knowledge of the current session and don't have a way to communicate with the client The Current property returns the instance of the Application class that is bound to the current session. It can be used just like any other component with Update or RunInContext to restore the session for the current thread. The advantage of using Current instead of the instance of a control or a page is to avoid to keep a reference to a component that may be disposed by the application.
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var current = Application.Current;
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var thread = new Thread(() => {
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Application.Update(current, () => {
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// code here is running in context.
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});
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});
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CurrentCulture
Desktop
EnableUnloadConfirmation
Boolean: Returns or sets whether the browser will ask the user to confirm unloading the current page.
This property attaches the window.onbeforeunload event. See https://developer.mozilla.org/en-US/docs/Web/API/WindowEventHandlers/onbeforeunload. It's not possible to determine whether the page is being unloaded because the user is trying to close the tab, close the browser, or is refreshing the page, or is taking any other action that may reload the page.
ExecutablePath
FavIcon
FavIconSource
Hash
IsAuthenticated
IsDisposed
Boolean: Indicates that the current application instance, which corresponds to the session, has been terminated and disposed.
IsExpired
IsSecure
IsTerminated
IsWebSocket
LicenseKey
Setting the LicenseKey programmatically has to be done before the application is loaded. The best place is the static constructor for the Program static class, or the static constructor of the main window (if defined in Default.js).
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static class Program
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{
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static Program()
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{
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Application.LicenseKey = "...";
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}
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}
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MainPage
OpenForms
OpenPages
Platform
ProductName
ProductVersion
String: Returns the product version associated with this application stored either in AssemblyInformationalVersionAttribute or AssemblyFileVersionAttribute.
QueryString
RightToLeft
Boolean: Returns or sets whether all the controls in the applications should operate using the right-to-left mode.
The value of this property is updated automatically when the current language changes if the value of "rightToLeft" in the application configuration file is set to "auto".
RuntimeMode
ServerName
String: Returns the server's host name, DNS alias, or IP address as it would appear in self-referencing URLs.
ServerPort
ServerVariables
Session
SessionCount
SessionId
ShowConsole
Displays a simple HTMl only debug console. Works with any browser also when the developer tools are not available.
ShowLoader
StartupPath
StartupUri
StartupUrl
Theme
You can create and modify a new custom theme using the ClientTheme class. The new theme can be based on an existing theme, can be empty, or can be initialized from a JSON string.
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// create a new custom theme cloned from the current theme.
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var myTheme = new ClientTheme("MyTheme", Application.Theme);
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// alter the buttonFace color.
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myTheme.Colors.buttonFace = "red";
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// update the current session using the new custom theme.
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Application.Theme = myTheme;
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You may also alter a global theme shared by all sessions.
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// change the buttonFace color in the current theme.
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// if the theme is one of the global themes, i.e. it was loaded
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// using Application.LoadTheme(name), then the change is also global.
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Application.Theme.Colors.buttonFace = "red";
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// since the theme objects are all dynamic and use a special DynamicObject
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// class part of the Wisej Framework, you can also use a string indexer
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// to address any field.
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Application.Theme.Colors["buttonFace"] = "red";
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Title
Uri
Uri: Returns the current Uri used either to launch or reload the application. It may be different from StartupUri.
Url
String: Returns the current URL used either to launch or reload the application. It may be different from StartupUrl.
User
UserAgent
UserHostAddress
UserHostName
UserIdentity
UserLanguages
Methods
AddEventFilter(filter)
Adds an event filter to monitor all the incoming events before they are routed to their respective component.
Parameter
Type
Description
AddTranslation(text, translation)
Adds the text and corresponding translation to the default locale on the client.
AlertAsync(message)
Instructs the browser to display a dialog with an optional message, and to wait until the user dismisses the dialog.
Parameter
Type
Description
Call(function, args)
Executes the JavaScript function on the client.
Call(function, callback, args)
Executes the JavaScript function on the client and receives the return value (or null) in the callback method.
CallAsync(function, args)
Asynchronously executes the JavaScript function on the client and returns an awaitable Task with the result of the remote call.
CancelFullScreen()
Cancels the fullscreen mode.
ConfirmAsync(message)
Instructs the browser to display a dialog with an optional message, and to wait until the user either confirms or cancels the dialog. until the user dismisses the dialog.
Parameter
Type
Description
Download(filePath, fileName)
Downloads the specified file on the client.
Download(image, fileName)
Downloads the specified image to the client.
Download(stream, fileName)
Downloads the bytes in the stream to the client.
DownloadAndOpen(target, filePath, fileName)
Downloads the specified file on the client.
DownloadAndOpen(target, image, fileName)
Downloads the specified image to the client.
DownloadAndOpen(target, stream, fileName)
Downloads the bytes in the stream to the client.
EndPolling()
Stops the polling requests from the client.
Eval(script)
Executes the JavaScript script on the client.
Parameter
Type
Description
Eval(script, callback)
Executes the JavaScript script on the client and receives the return value (or null) in the callback method.
EvalAsync(script)
Asynchronously executes the JavaScript script on the client and returns an awaitable Task with the result of the remote call.
Parameter
Type
Description
Exit()
Terminates the application and the corresponding session.
FindComponent(match)
Find the first component that matches the conditions defined in the predicate function.
Parameter
Type
Description
This method lets an application find any live component in the current session.
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// Find the first component that is a Button with Text = "OK"
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var button = Application.FindComponent(c => c is Button && ((Button)c).Text == "OK");
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FindComponents(match)
Finds all the components that match the conditions in the predicate function.
Parameter
Type
Description
match
This method lets an application iterate through all the live components in the current session.
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// List all text boxes that are read only in all forms.
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var list = Application.FindComponents(c => c is TextBox && ((TextBox)c).ReadOnly);
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LoadAssembly(filePath)
Loads an assembly given the file name or path.
Parameter
Type
Description
This method loads the assembly and, if the assembly contains Wisej components that need embedded resources - like JavaScript classes or CSS styles - that are embedded in the assembly, notifies the client with the URL to load the additional resources dynamically.
LoadComponent(filePath, className)
Creates an instance of the specified component from the assembly.
Returns: IWisejComponent. An instance of a Wisej component implementing the IWisejComponent interface.
LoadPackages(packages, callback)
LoadPackagesAsync(packages)
Parameter
Type
Description
LoadTheme(name, mixins)
Changes the current theme.
MapPath(path)
Returns the full file path in relation to the application's project directory.
Parameter
Type
Description
Navigate(url, target)
Navigate to the specified URL.
Play(type)
Plays one of the built-in sounds
Parameter
Type
Description
Play(soundUrl)
Plays a sound.
Parameter
Type
Description
Post(callback)
Executes the callback method after all processing is completed and before updating the client.
Parameter
Type
Description
callback
Method to invoke after the request has completed but before sending the response to the server.
The Post() method is similar to the BeginInvoke() method used by desktop applications. It allows you to execute a block of code out of sync with the current execution flow.
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void Test() {
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Application.Post(() => {
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this.listBox.Items.Add("1");
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});
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this.listBox.Items.Add("2");
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// The items will be added in this order: "2", "1".
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}
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Print(window)
Prints the specified window.
Parameter
Type
Description
The window is printed without the caption or the borders, if present.
Print()
Prints the entire browser window.
PromptAsync(message, defaultValue)
Instructs the browser to display a dialog with an optional message prompting the user to input some text, and to wait until the user either submits the text or cancels the dialog.
Reload()
Causes the application to reload on the browser.
RemoveEventFilter(filter)
Removes the filter from the list of registered event filters.
Parameter
Type
Description
filter
RequestFullScreen()
Requests the browser to enable fullscreen mode if supported.
RunInContext(context, action)
Executes the callback in context.
Parameter
Type
Description
context
The application context to update. It can be any Wisej component or the IWisejComponent returned by the property Context.
action
Function to execute in context. The code in the function can access all the static Application properties when executed from an out-of-bound thread.
StartPolling(interval)
Instructs the client to start polling the server for UI changes at the specified interval when a WebSocket connection is not available.
Parameter
Type
Description
Calling this method when IsWebSocket is true has no effect. Use client side polling when you know that your code will start a background task that needs to update the client asynchronously (push updates) and your server or clients don't support WebSocket connections. Once the background tasks are completed call EndPolling to reduce the incoming requests from the client.
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// this has not effect when the client and server are connected using WebSocket.
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Application.StartPolling(1000);
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Application.StartTask(() => {
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for (int i = 0; i < 100; i++) {
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this.label1.Text = "Counting..." + i;
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Thread.Sleep(1000);
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}
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// this has not effect when the client and server are NOT connected using WebSocket.
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Application.Update(this);
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// this has not effect when the client and server are connected using WebSocket.
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Application.EndPolling();
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});
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Throws:
- The interval specified is less than 1.
StartTask(action)
Starts a new task within the current application context and returns immediately. See also BackgroundTasks.
Parameter
Type
Description
The task runs in the background but it's still capable of updating the client asynchronously when working with WebSocket by calling the Update method to push the UI updates to the client browser. If you want to support background updates for clients or servers that can't use the WebSocket connection, you can either add a Timer component to the parent container to force period requests to the server, or you can use the StartPolling and EndPolling methods.
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Application.StartTask(() => {
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for (int i = 0; i < 100; i++) {
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this.label1.Text = "Counting..." + i;
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// just wait a bit or it's too fast.
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Thread.Sleep(1000);
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Application.Update(this);
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}
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});
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StartTask(action)
Starts a new task with a return value within the current application context and returns immediately. See also BackgroundTasks.
Parameter
Type
Description
The task runs in the background but it's still capable of updating the client asynchronously when working with WebSocket by calling the Update method to push the UI updates to the client browser. The generics overload of StartTask allows the task to return a value. You can use this with the async/await pattern and asynchronously wait for the task to complete. If you want to support background updates for clients or servers that can't use the WebSocket connection, you can either add a Timer component to the parent container to force period requests to the server, or you can use the StartPolling and EndPolling methods.
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string text = await Application.StartTask(() => {
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string value = "";
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for (int i = 0; i < 100; i++) {
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value += i.ToString();
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// just wait a bit or it's too fast.
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Thread.Sleep(100);
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}
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return value;
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});
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this.label.Text = text;
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Application.Update(this);
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Note that you don't have to specify the type in the angular brackets, the compiler will automatically detect the type from the return value of the asynchronous function.
StartTimer(dueTime, period, callback)
You must save a reference to the returned Timer or the Garbage Collector will stop and dispose the timer. To alter the invocation period user Timer.Changer(), or stop the timer simply use Timer.Dispose(). See system.threading.
Update(context, action)
Executes the optional callback in context and pushes all the pending updates to the client when in WebSocket mode.
Parameter
Type
Description
context
The application context to update. It can be any Wisej component or the IWisejComponent returned by the property Context.
action
Function to execute in context. The code in the function can access all the static Application properties when executed from an out-of-bound thread.
Use this method when you need to update the client asynchronously from an out-of-bound thread (different thread, not originating from a client request). You can call this method at the end of the code that updates the UI:
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Application.StartTask(() => {
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for (int i = 0; i < 100; i++) {
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this.label1.Text = "Counting..." + i;
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// just wait a bit or it's too fast.
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Thread.Sleep(1000);
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}
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Application.Update(this);
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});
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Or you can use the optional action function to enclose the code that updates the UI in a block and ensure that the client is updated when the code block exits:
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Application.StartTask(() => {
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Application.Update(this, () => {
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for (int i = 0; i < 100; i++) {
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this.label1.Text = "Counting..." + i;
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// just wait a bit or it's too fast.
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Thread.Sleep(1000);
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}
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});
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});
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Events
ActiveWindowChanged
ApplicationExit
ApplicationRefresh
EventHandler Fired when the application is reloaded in the browser because the user hit refresh or changed the URL.
ApplicationStart
BeforeInstallPrompt
EventHandler Fired when the browser fires the "beforeinstallprompt" event. Corresponds to BeforeInstallPromptEvent.
BeginRequest
BrowserSizeChanged
BrowserTabActivated
BrowserTabDeactivated
CultureChanged
EndRequest
FocusedControlChanged
HashChanged
Idle
EventHandler Fired when the current thread has completed processing all the events and before the response is sent back to the client.
ResponsiveProfileChanged
RightToLeftChanged
SessionTimeout
The default behavior built-in Wisej is to display a dialog asking the user to prolong the session. Set Handled to true to stop the default behavior.