Hardcodet.Wpf.TaskbarNotification Supported icons for the tray's balloon messages. The balloon message is displayed without an icon. An information is displayed. A warning is displayed. An error is displayed. Resolves the current tray position. Gets the position of the system tray. Tray coordinates. Win API struct providing coordinates for a single point. X coordinate. Y coordinate. Callback delegate which is used by the Windows API to submit window messages. Win API WNDCLASS struct - represents a single window. Used to receive window messages. Defines flags that define when a popup is being displyed. The item is displayed if the user clicks the tray icon with the left mouse button. The item is displayed if the user clicks the tray icon with the right mouse button. The item is displayed if the user double-clicks the tray icon. The item is displayed if the user clicks the tray icon with the left or the right mouse button. The item is displayed if the user clicks the tray icon with the left mouse button or if a double-click is being performed. The item is displayed if the user clicks the tray icon with the middle mouse button. The item is displayed whenever a click occurs. Helper class used by routed events of the class. A static helper method to raise a routed event on a target UIElement or ContentElement. UIElement or ContentElement on which to raise the event RoutedEventArgs to use when raising the event A static helper method that adds a handler for a routed event to a target UIElement or ContentElement. UIElement or ContentElement that listens to the event Event that will be handled Event handler to be added A static helper method that removes a handler for a routed event from a target UIElement or ContentElement. UIElement or ContentElement that listens to the event Event that will no longer be handled Event handler to be removed Win32 API imports. Creates, updates or deletes the taskbar icon. Creates the helper window that receives messages from the taskar icon. Processes a default windows procedure. Registers the helper window class. Registers a listener for a window message. Used to destroy the hidden helper window that receives messages from the taskbar icon. Gives focus to a given window. Gets the maximum number of milliseconds that can elapse between a first click and a second click for the OS to consider the mouse action a double-click. The maximum amount of time, in milliseconds, that can elapse between a first click and a second click for the OS to consider the mouse action a double-click. Gets the screen coordinates of the current mouse position. Event flags for clicked events. The mouse was moved withing the taskbar icon's area. The right mouse button was clicked. The left mouse button was clicked. The right mouse button was released. The left mouse button was released. The middle mouse button was clicked. The middle mouse button was released. The taskbar icon was double clicked. The balloon tip was clicked. Main operations performed on the function. The taskbar icon is being created. The settings of the taskbar icon are being updated. The taskbar icon is deleted. Focus is returned to the taskbar icon. Currently not in use. Shell32.dll version 5.0 and later only. Instructs the taskbar to behave according to the version number specified in the uVersion member of the structure pointed to by lpdata. This message allows you to specify whether you want the version 5.0 behavior found on Microsoft Windows 2000 systems, or the behavior found on earlier Shell versions. The default value for uVersion is zero, indicating that the original Windows 95 notify icon behavior should be used. A struct that is submitted in order to configure the taskbar icon. Provides various members that can be configured partially, according to the values of the that were defined. Size of this structure, in bytes. Handle to the window that receives notification messages associated with an icon in the taskbar status area. The Shell uses hWnd and uID to identify which icon to operate on when Shell_NotifyIcon is invoked. Application-defined identifier of the taskbar icon. The Shell uses hWnd and uID to identify which icon to operate on when Shell_NotifyIcon is invoked. You can have multiple icons associated with a single hWnd by assigning each a different uID. This feature, however is currently not used. Flags that indicate which of the other members contain valid data. This member can be a combination of the NIF_XXX constants. Application-defined message identifier. The system uses this identifier to send notifications to the window identified in hWnd. A handle to the icon that should be displayed. Just Icon.Handle. String with the text for a standard ToolTip. It can have a maximum of 64 characters including the terminating NULL. For Version 5.0 and later, szTip can have a maximum of 128 characters, including the terminating NULL. State of the icon. Remember to also set the . A value that specifies which bits of the state member are retrieved or modified. For example, setting this member to causes only the item's hidden state to be retrieved. String with the text for a balloon ToolTip. It can have a maximum of 255 characters. To remove the ToolTip, set the NIF_INFO flag in uFlags and set szInfo to an empty string. Mainly used to set the version when is invoked with . However, for legacy operations, the same member is also used to set timouts for balloon ToolTips. String containing a title for a balloon ToolTip. This title appears in boldface above the text. It can have a maximum of 63 characters. Adds an icon to a balloon ToolTip, which is placed to the left of the title. If the member is zero-length, the icon is not shown. Windows XP (Shell32.dll version 6.0) and later.
- Windows 7 and later: A registered GUID that identifies the icon. This value overrides uID and is the recommended method of identifying the icon.
- Windows XP through Windows Vista: Reserved. Windows Vista (Shell32.dll version 6.0.6) and later. The handle of a customized balloon icon provided by the application that should be used independently of the tray icon. If this member is non-NULL and the flag is set, this icon is used as the balloon icon.
If this member is NULL, the legacy behavior is carried out. Creates a default data structure that provides a hidden taskbar icon without the icon being set. Indicates which members of a structure were set, and thus contain valid data or provide additional information to the ToolTip as to how it should display. The message ID is set. The notification icon is set. The tooltip is set. State information () is set. This applies to both and . The balloon ToolTip is set. Accordingly, the following members are set: , , , and . Windows Vista (Shell32.dll version 6.0.6) and later. If the ToolTip cannot be displayed immediately, discard it.
Use this flag for ToolTips that represent real-time information which would be meaningless or misleading if displayed at a later time. For example, a message that states "Your telephone is ringing."
This modifies and must be combined with the flag. Windows Vista (Shell32.dll version 6.0.6) and later. Use the standard ToolTip. Normally, when uVersion is set to NOTIFYICON_VERSION_4, the standard ToolTip is replaced by the application-drawn pop-up user interface (UI). If the application wants to show the standard tooltip in that case, regardless of whether the on-hover UI is showing, it can specify NIF_SHOWTIP to indicate the standard tooltip should still be shown.
Note that the NIF_SHOWTIP flag is effective until the next call to Shell_NotifyIcon. The state of the icon - can be set to hide the icon. The icon is visible. Hide the icon. The notify icon version that is used. The higher the version, the more capabilities are available. Default behavior (legacy Win95). Expects a size of 488. Behavior representing Win2000 an higher. Expects a size of 504. Extended tooltip support, which is available for Vista and later. Flags that define the icon that is shown on a balloon tooltip. No icon is displayed. An information icon is displayed. A warning icon is displayed. An error icon is displayed. Windows XP Service Pack 2 (SP2) and later. Use a custom icon as the title icon. Windows XP (Shell32.dll version 6.0) and later. Do not play the associated sound. Applies only to balloon ToolTips. Windows Vista (Shell32.dll version 6.0.6) and later. The large version of the icon should be used as the balloon icon. This corresponds to the icon with dimensions SM_CXICON x SM_CYICON. If this flag is not set, the icon with dimensions XM_CXSMICON x SM_CYSMICON is used.
- This flag can be used with all stock icons.
- Applications that use older customized icons (NIIF_USER with hIcon) must provide a new SM_CXICON x SM_CYICON version in the tray icon (hIcon). These icons are scaled down when they are displayed in the System Tray or System Control Area (SCA).
- New customized icons (NIIF_USER with hBalloonIcon) must supply an SM_CXICON x SM_CYICON version in the supplied icon (hBalloonIcon). Windows 7 and later. Receives messages from the taskbar icon through window messages of an underlying helper window. The ID of messages that are received from the the taskbar icon. The ID of the message that is being received if the taskbar is (re)started. Used to track whether a mouse-up event is just the aftermath of a double-click and therefore needs to be suppressed. A delegate that processes messages of the hidden native window that receives window messages. Storing this reference makes sure we don't loose our reference to the message window. Creates a new message sink that receives message from a given taskbar icon. Creates a dummy instance that provides an empty pointer rather than a real window handler.
Used at design time. Creates the helper message window that is used to receive messages from the taskbar icon. Callback method that receives messages from the taskbar area. Processes incoming system messages. Callback ID. If the version is or higher, this parameter can be used to resolve mouse coordinates. Currently not in use. Provides information about the event. Disposes the object. This method is not virtual by design. Derived classes should override . This destructor will run only if the method does not get called. This gives this base class the opportunity to finalize. Important: Do not provide destructors in types derived from this class. Removes the windows hook that receives window messages and closes the underlying helper window. Window class ID. Handle for the message window. The version of the underlying icon. Defines how incoming messages are interpreted. The custom tooltip should be closed or hidden. Fired in case the user clicked or moved within the taskbar icon area. Fired if a balloon ToolTip was either displayed or closed (indicated by the boolean flag). Fired if the taskbar was created or restarted. Requires the taskbar icon to be reset. Set to true as soon as Dispose has been invoked. A WPF proxy to for a taskbar icon (NotifyIcon) that sits in the system's taskbar notification area ("system tray"). Contains declarations of WPF dependency properties and events. Category name that is set on designer properties. Represents the current icon data. Receives messages from the taskbar icon. An action that is being invoked if the fires. A timer that is used to differentiate between single and double clicks. A timer that is used to close open balloon tooltips. Inits the taskbar icon and registers a message listener in order to receive events from the taskbar area. Shows a custom control as a tooltip in the tray location. An optional animation for the popup. The time after which the popup is being closed. Submit null in order to keep the balloon open inde If is a null reference. Resets the closing timeout, which effectively keeps a displayed balloon message open until it is either closed programmatically through or due to a new message being displayed. Closes the current , if the property is set. Timer-invoke event which closes the currently open balloon and resets the dependency property. Processes mouse events, which are bubbled through the class' routed events, trigger certain actions (e.g. show a popup), or both. Event flag. Displays a custom tooltip, if available. This method is only invoked for Windows Vista and above. Whether to show or hide the tooltip. Creates a control that either wraps the currently set control or the string.
If itself is already a instance, it will be used directly. We use a rather than because there was no way to prevent a popup from causing cyclic open/close commands if it was placed under the mouse. ToolTip internally uses a Popup of its own, but takes advance of Popup's internal property which prevents this issue. Sets tooltip settings for the class depending on defined dependency properties and OS support. Creates a control that either wraps the currently set control or the string.
If itself is already a instance, it will be used directly. We use a rather than because there was no way to prevent a popup from causing cyclic open/close commands if it was placed under the mouse. ToolTip internally uses a Popup of its own, but takes advance of Popup's internal property which prevents this issue. Displays the control if it was set. Displays the if it was set. Bubbles events if a balloon ToolTip was displayed or removed. Whether the ToolTip was just displayed or removed. Displays a balloon tip with the specified title, text, and icon in the taskbar for the specified time period. The title to display on the balloon tip. The text to display on the balloon tip. A symbol that indicates the severity. Displays a balloon tip with the specified title, text, and a custom icon in the taskbar for the specified time period. The title to display on the balloon tip. The text to display on the balloon tip. A custom icon. If is a null reference. Invokes in order to display a given balloon ToolTip. The title to display on the balloon tip. The text to display on the balloon tip. Indicates what icon to use. A handle to a custom icon, if any, or . Hides a balloon ToolTip, if any is displayed. Performs a delayed action if the user requested an action based on a single click of the left mouse.
This method is invoked by the . Sets the version flag for the . Recreates the taskbar icon if the whole taskbar was recreated (e.g. because Explorer was shut down). Creates the taskbar icon. This message is invoked during initialization, if the taskbar is restarted, and whenever the icon is displayed. Closes the taskbar icon if required. Recalculates OS coordinates in order to support WPFs coordinate system if OS scaling (DPIs) is not 100%. Checks if the object has been disposed and raises a in case the flag is true. Disposes the class if the application exits. This destructor will run only if the method does not get called. This gives this base class the opportunity to finalize. Important: Do not provide destructors in types derived from this class. Disposes the object. This method is not virtual by design. Derived classes should override . Closes the tray and releases all resources. Dispose(bool disposing) executes in two distinct scenarios. If disposing equals true, the method has been called directly or indirectly by a user's code. Managed and unmanaged resources can be disposed. If disposing equals false, the method has been called by the runtime from inside the finalizer and you should not reference other objects. Only unmanaged resources can be disposed. Check the property to determine whether the method has already been called. TrayPopupResolved Read-Only Dependency Property A read-only dependency property that returns the that is being displayed in the taskbar area based on a user action. Provides a secure method for setting the TrayPopupResolved property. This dependency property indicates .... The new value for the property. TrayToolTipResolved Read-Only Dependency Property A read-only dependency property that returns the that is being displayed. Provides a secure method for setting the property. The new value for the property. CustomBalloon Read-Only Dependency Property Maintains a currently displayed custom balloon. Provides a secure method for setting the property. The new value for the property. Resolves an image source and updates the property accordingly. A static callback listener which is being invoked if the dependency property has been changed. Invokes the instance method of the changed instance. The currently processed owner of the property. Provides information about the updated property. Handles changes of the dependency property. As WPF internally uses the dependency property system and bypasses the property wrapper, updates of the property's value should be handled here. Provides information about the updated property. A tooltip text that is being displayed if no custom was set or if custom tooltips are not supported. A static callback listener which is being invoked if the dependency property has been changed. Invokes the instance method of the changed instance. The currently processed owner of the property. Provides information about the updated property. Handles changes of the dependency property. As WPF internally uses the dependency property system and bypasses the property wrapper, updates of the property's value should be handled here. Provides information about the updated property. A custom UI element that is displayed as a tooltip if the user hovers over the taskbar icon. Works only with Vista and above. Accordingly, you should make sure that the property is set as well. A static callback listener which is being invoked if the dependency property has been changed. Invokes the instance method of the changed instance. The currently processed owner of the property. Provides information about the updated property. Handles changes of the dependency property. As WPF internally uses the dependency property system and bypasses the property wrapper, updates of the property's value should be handled here. Provides information about the updated property. A control that is displayed as a popup when the taskbar icon is clicked. A static callback listener which is being invoked if the dependency property has been changed. Invokes the instance method of the changed instance. The currently processed owner of the property. Provides information about the updated property. Handles changes of the dependency property. As WPF internally uses the dependency property system and bypasses the property wrapper, updates of the property's value should be handled here. Provides information about the updated property. Defines what mouse events display the context menu. Defaults to . Defines what mouse events trigger the . Default is . A static callback listener which is being invoked if the dependency property has been changed. Invokes the instance method of the changed instance. The currently processed owner of the property. Provides information about the updated property. Handles changes of the dependency property. As WPF internally uses the dependency property system and bypasses the property wrapper, updates of the property's value should be handled here. Provides information about the updated property. Updates the of a given . This method only updates target elements that do not already have a data context of their own, and either assigns the of the NotifyIcon, or the NotifyIcon itself, if no data context was assigned at all. A static callback listener which is being invoked if the dependency property has been changed. Invokes the instance method of the changed instance. The currently processed owner of the property. Provides information about the updated property. Handles changes of the dependency property. As WPF internally uses the dependency property system and bypasses the property wrapper, updates of the property's value should be handled here. Provides information about the updated property. A static callback listener which is being invoked if the dependency property has been changed. Invokes the instance method of the changed instance. The currently processed owner of the property. Provides information about the updated property. Releases the old and updates the new property in order to reflect both the NotifyIcon's property and have the assigned. Provides information about the updated property. Associates a command that is being executed if the tray icon is being double clicked. Command parameter for the . The target of the command that is fired if the notify icon is double clicked. Associates a command that is being executed if the tray icon is being double clicked. Command parameter for the . The target of the command that is fired if the notify icon is clicked. TrayLeftMouseDown Routed Event A helper method to raise the TrayLeftMouseDown event. A static helper method to raise the TrayLeftMouseDown event on a target element. UIElement or ContentElement on which to raise the event TrayRightMouseDown Routed Event A helper method to raise the TrayRightMouseDown event. A static helper method to raise the TrayRightMouseDown event on a target element. UIElement or ContentElement on which to raise the event TrayMiddleMouseDown Routed Event A helper method to raise the TrayMiddleMouseDown event. A static helper method to raise the TrayMiddleMouseDown event on a target element. UIElement or ContentElement on which to raise the event TrayLeftMouseUp Routed Event A helper method to raise the TrayLeftMouseUp event. A static helper method to raise the TrayLeftMouseUp event on a target element. UIElement or ContentElement on which to raise the event TrayRightMouseUp Routed Event A helper method to raise the TrayRightMouseUp event. A static helper method to raise the TrayRightMouseUp event on a target element. UIElement or ContentElement on which to raise the event TrayMiddleMouseUp Routed Event A helper method to raise the TrayMiddleMouseUp event. A static helper method to raise the TrayMiddleMouseUp event on a target element. UIElement or ContentElement on which to raise the event TrayMouseDoubleClick Routed Event A helper method to raise the TrayMouseDoubleClick event. A static helper method to raise the TrayMouseDoubleClick event on a target element. UIElement or ContentElement on which to raise the event TrayMouseMove Routed Event A helper method to raise the TrayMouseMove event. A static helper method to raise the TrayMouseMove event on a target element. UIElement or ContentElement on which to raise the event TrayBalloonTipShown Routed Event A helper method to raise the TrayBalloonTipShown event. A static helper method to raise the TrayBalloonTipShown event on a target element. UIElement or ContentElement on which to raise the event TrayBalloonTipClosed Routed Event A helper method to raise the TrayBalloonTipClosed event. A static helper method to raise the TrayBalloonTipClosed event on a target element. UIElement or ContentElement on which to raise the event TrayBalloonTipClicked Routed Event A helper method to raise the TrayBalloonTipClicked event. A static helper method to raise the TrayBalloonTipClicked event on a target element. UIElement or ContentElement on which to raise the event TrayContextMenuOpen Routed Event A helper method to raise the TrayContextMenuOpen event. A static helper method to raise the TrayContextMenuOpen event on a target element. UIElement or ContentElement on which to raise the event PreviewTrayContextMenuOpen Routed Event A helper method to raise the PreviewTrayContextMenuOpen event. A static helper method to raise the PreviewTrayContextMenuOpen event on a target element. UIElement or ContentElement on which to raise the event TrayPopupOpen Routed Event A helper method to raise the TrayPopupOpen event. A static helper method to raise the TrayPopupOpen event on a target element. UIElement or ContentElement on which to raise the event PreviewTrayPopupOpen Routed Event A helper method to raise the PreviewTrayPopupOpen event. A static helper method to raise the PreviewTrayPopupOpen event on a target element. UIElement or ContentElement on which to raise the event TrayToolTipOpen Routed Event A helper method to raise the TrayToolTipOpen event. A static helper method to raise the TrayToolTipOpen event on a target element. UIElement or ContentElement on which to raise the event PreviewTrayToolTipOpen Routed Event A helper method to raise the PreviewTrayToolTipOpen event. A static helper method to raise the PreviewTrayToolTipOpen event on a target element. UIElement or ContentElement on which to raise the event TrayToolTipClose Routed Event A helper method to raise the TrayToolTipClose event. A static helper method to raise the TrayToolTipClose event on a target element. UIElement or ContentElement on which to raise the event PreviewTrayToolTipClose Routed Event A helper method to raise the PreviewTrayToolTipClose event. A static helper method to raise the PreviewTrayToolTipClose event on a target element. UIElement or ContentElement on which to raise the event PopupOpened Attached Routed Event Adds a handler for the PopupOpened attached event UIElement or ContentElement that listens to the event Event handler to be added Removes a handler for the PopupOpened attached event UIElement or ContentElement that listens to the event Event handler to be removed A static helper method to raise the PopupOpened event on a target element. UIElement or ContentElement on which to raise the event ToolTipOpened Attached Routed Event Adds a handler for the ToolTipOpened attached event UIElement or ContentElement that listens to the event Event handler to be added Removes a handler for the ToolTipOpened attached event UIElement or ContentElement that listens to the event Event handler to be removed A static helper method to raise the ToolTipOpened event on a target element. UIElement or ContentElement on which to raise the event ToolTipClose Attached Routed Event Adds a handler for the ToolTipClose attached event UIElement or ContentElement that listens to the event Event handler to be added Removes a handler for the ToolTipClose attached event UIElement or ContentElement that listens to the event Event handler to be removed A static helper method to raise the ToolTipClose event on a target element. UIElement or ContentElement on which to raise the event BalloonShowing Attached Routed Event Adds a handler for the BalloonShowing attached event UIElement or ContentElement that listens to the event Event handler to be added Removes a handler for the BalloonShowing attached event UIElement or ContentElement that listens to the event Event handler to be removed A static helper method to raise the BalloonShowing event on a target element. UIElement or ContentElement on which to raise the event The instance that manages the balloon. BalloonClosing Attached Routed Event Adds a handler for the BalloonClosing attached event UIElement or ContentElement that listens to the event Event handler to be added Removes a handler for the BalloonClosing attached event UIElement or ContentElement that listens to the event Event handler to be removed A static helper method to raise the BalloonClosing event on a target element. UIElement or ContentElement on which to raise the event The instance that manages the balloon. An attached property that is assigned to displayed UI elements (balloos, tooltips, context menus), and that can be used to bind to this control. The attached property is being derived, so binding is quite straightforward: Gets the ParentTaskbarIcon property. This dependency property indicates .... Sets the ParentTaskbarIcon property. This dependency property indicates .... Registers properties. Indicates whether the taskbar icon has been created or not. Indicates whether custom tooltips are supported, which depends on the OS. Windows Vista or higher is required in order to support this feature. Checks whether a non-tooltip popup is currently opened. Set to true as soon as Dispose has been invoked. Gets the TrayPopupResolved property. Returns a which is either the control itself or a control that contains the . Gets the TrayToolTipResolved property. Returns a control that was created in order to display either or . A custom popup that is being displayed in the tray area in order to display messages to the user. Gets or sets the icon to be displayed. This is not a dependency property - if you want to assign the property through XAML, please use the dependency property. A property wrapper for the dependency property:
Resolves an image source and updates the property accordingly. A property wrapper for the dependency property:
A tooltip text that is being displayed if no custom was set or if custom tooltips are not supported. A property wrapper for the dependency property:
A custom UI element that is displayed as a tooltip if the user hovers over the taskbar icon. Works only with Vista and above. Accordingly, you should make sure that the property is set as well. A property wrapper for the dependency property:
A control that is displayed as a popup when the taskbar icon is clicked. A property wrapper for the dependency property:
Defines what mouse events display the context menu. Defaults to . A property wrapper for the dependency property:
Defines what mouse events trigger the . Default is . A property wrapper for the dependency property:
Associates a command that is being executed if the tray icon is being double clicked. A property wrapper for the dependency property:
Command parameter for the . A property wrapper for the dependency property:
The target of the command that is fired if the notify icon is double clicked. A property wrapper for the dependency property:
Associates a command that is being executed if the tray icon is being left-clicked. A property wrapper for the dependency property:
Command parameter for the . A property wrapper for the dependency property:
The target of the command that is fired if the notify icon is clicked. Occurs when the user presses the left mouse button. Occurs when the presses the right mouse button. Occurs when the user presses the middle mouse button. Occurs when the user releases the left mouse button. Occurs when the user releases the right mouse button. Occurs when the user releases the middle mouse button. Occurs when the user double-clicks the taskbar icon. Occurs when the user moves the mouse over the taskbar icon. Occurs when a balloon ToolTip is displayed. Occurs when a balloon ToolTip was closed. Occurs when the user clicks on a balloon ToolTip. Bubbled event that occurs when the context menu of the taskbar icon is being displayed. Tunneled event that occurs when the context menu of the taskbar icon is being displayed. Bubbled event that occurs when the custom popup is being opened. Tunneled event that occurs when the custom popup is being opened. Bubbled event that occurs when the custom ToolTip is being displayed. Tunneled event that occurs when the custom ToolTip is being displayed. Bubbled event that occurs when a custom tooltip is being closed. Tunneled event that occurs when a custom tooltip is being closed. Util and extension methods. Creates an transparent window without dimension that can be used to temporarily obtain focus and/or be used as a window message sink. Empty window. Updates the taskbar icons with data provided by a given instance. Configuration settings for the NotifyIcon. Operation on the icon (e.g. delete the icon). True if the data was successfully written. See Shell_NotifyIcon documentation on MSDN for details. Updates the taskbar icons with data provided by a given instance. Configuration settings for the NotifyIcon. Operation on the icon (e.g. delete the icon). Defines which members of the structure are set. True if the data was successfully written. See Shell_NotifyIcon documentation on MSDN for details. Gets a enum value that matches a given . Reads a given image resource into a WinForms icon. Image source pointing to an icon file (*.ico). An icon object that can be used with the taskbar area. Checks a list of candidates for equality to a given reference value. The evaluated value. A liste of possible values that are regarded valid. True if one of the submitted matches the evaluated value. If the parameter itself is null, too, the method returns false as well, which allows to check with null values, too. If is a null reference. Checks if a given is a match for an effectively pressed mouse button. Executes a given command if its method indicates it can run. The command to be executed, or a null reference. An optional parameter that is associated with the command. The target element on which to raise the command. Returns a dispatcher for multi-threaded scenarios Checks whether the is bound or not. The element to be checked. True if the data context property is being managed by a binding expression. If is a null reference. Checks whether the application is currently in design mode.