Class

WebSDKUIControl

Description

WebSDKUIControl is a direct subclass of WebUIControl, but because WebUIControl inherits from WebControl it means that WebSDKUIControl doesn't actually have a direct relationship with WebSDKControl.

Constants

These constants are designed to be used with the WebSDKUIControl to show icons at the Navigator and Library.

Name

Description

NavigatorIcon

This constant is used to override the icon of your control in the Navigator. Using the WebSDKIconConverter, place the Base64 icon data into the value of this constant.

LibraryIcon

This constant is used to override the icon of your control in the Library. Using the WebSDKIconConverter, place the Base64 icon data into the value of this constant.

Enumerations

WebSDKUIControl.Indicators

Indicators

Specifies the color scheme for the control.

Name

Default

Primary

Secondary

Success

Danger

Warning

Info

Light

Dark

Link

Property descriptions

WebSDKUIControl.ContextualMenu

ContextualMenu As WebMenuItem

If you assign a WebMenuItem to the control, it will be displayed when the user right-clicks the control.

On a WebPage, you can disable/remove the default contextual menu by an empty WebMenuItem class object to this property.

This code populates a contextual menu in the Shown event of the control.

Var menu As New WebMenuItem

menu.AddMenuItem("One")
menu.AddMenuItem("Two")
menu.AddMenuItem("Three")
Me.ContextualMenu = menu

The menu selection is then handled by the ContextualMenuSelected event when the user right-clicks on the control. For example, it can be of the form:

Select Case hitItem.Text
Case "One"
  MessageBox("One")
Case "Two"
  MessageBox("Two")
Case "Three"
  MessageBox("Three")
End Select

WebSDKUIControl.ControlID

ControlID As String

Identifies the control on a per session basis.

This property is read-only.

WebSDKUIControl.Enabled

Enabled As Boolean

When True the WebControl is drawn enabled and responds to user action. When False, the control appears as disabled and does not respond to user actions.

In the case of WebTimer, when set to False this disables and stops the WebTimer. When set to True, it starts the WebTimer.

Disable a button when a check box value changes:

If AllowSaveCheckBox.Value Then
  SaveButton.Enabled = True
Else
  AllowSaveButton.Enabled = False
End If

WebSDKUIControl.Height

Height As Integer

The height (in pixels) of the control.

WebSDKUIControl.Indicator

Indicator As WebUIControl.Indicators

The color scheme for the control.

This example sets the indicator of the button to Danger:

Button1.Indicator = WebUIControl.Indicators.Danger

WebSDKUIControl.Left

Left As Integer

The position of the left side of the WebUIControl in pixels, relative to the web page.

WebSDKUIControl.LockBottom

LockBottom As Boolean

Determines whether the bottom edge of the control should stay at a set distance from the bottom edge of the parent control, if there is one, or the owning web page.

WebSDKUIControl.LockHorizontal

LockHorizontal As Boolean

LockHorizontal overrides LockLeft and LockRight. It allows you to proportionally lock a control's position to the center of its parent control (or web page).

For example, if you place a control in the center of the page and sets both LockHorizontal and LockVertical, the control will stay in the center of the page.

WebSDKUIControl.LockLeft

LockLeft As Boolean

Determines whether the left edge of the control should stay at a set distance from the left edge of the parent control, if there is one, or the owning web page.

WebSDKUIControl.LockRight

LockRight As Boolean

Determines whether the right edge of the control should stay at a set distance from the right edge of the parent control, if there is one, or the owning web page.

WebSDKUIControl.LockTop

LockTop As Boolean

Determines whether the top edge of the control should stay at a set distance from the top edge of the parent control, if there is one, or the owning web page.

WebSDKUIControl.LockVertical

LockVertical As Boolean

LockVertical overrides LockTop and LockBottom. It allows you to proportionally lock a control's position to keep it centered within the parent control or web page.

For example, if you place a control in the center of the page, and sets both LockHorizontal and LockVertical, the control will stay in the center of the page.

WebSDKUIControl.Name

Name As String

The name of the control.

This property is read-only.

WebSDKUIControl.Page

Page As WebPage

Identifies the web page that contains the control.

This property is read-only.

WebSDKUIControl.PanelIndex

PanelIndex As Integer

If the control has been placed on a WebTabPanel or WebPagePanel control, this is the panel (page/tab) that the control is on. If the control is not on a panel, it returns -1.

The first panel is numbered zero. If the control has been placed on a panel of a WebTabPanel or WebPagePanel control, it returns the panel number. If the control is not on a WebPagePanel or WebTabPanel, it returns -1. If you change the PanelIndex to a nonexistent panel, the control will disappear until you give it a PanelIndex value that corresponds to a panel that exists.

If you are looking to change the currently selected panel (page/tab), use SelectedPanelIndex.

This code displays the panel index of the control that is on the page.

MessageBox(Me.SelectedPanelIndex.ToString)

WebSDKUIControl.Parent

Parent As WebView

Used to get the control's parent control or page. If the parent control is a WebContainer, then it returns the WebContainer. If it is on a WebPage, it returns the WebPage.

This property is read-only.

WebSDKUIControl.TabIndex

TabIndex As Integer

The WebUIControl's control's position in the Tab Order. The control with a TabIndex of 0 is the first WebUIControl to get the focus when the page opens in the browser.

This example sets the control's TabIndex.

Me.TabIndex = 2

WebSDKUIControl.Tooltip

Tooltip As WebToolTip

Text of a message displayed as a tooltip.

The tip is displayed when the user places the mouse on the control and leaves it there.

This code in the Shown event of a Button sets the tooltip:

Me.Tooltip = "Save changes"

WebSDKUIControl.Top

Top As Integer

The top of the control in local coordinates relative to the web page.

WebSDKUIControl.Visible

Visible As Boolean

If True, the control is drawn. If False, it's not.

Hide a control based on a checkbox setting:

If ShowEmailCheckbox.Value Then
  EmailField.Visible = True
Else
  EmailField.Visible = False
End If

WebSDKUIControl.Width

Width As Integer

The width (in pixels) of the web control.

This code in the Shown event handler increases the size of the control:

Me.Width = Me.Width + 50

Method descriptions

WebSDKUIControl.AcceptPictureDrop

AcceptPictureDrop(dragActionType As WebDragItem.DragActionTypes = WebDragItem.DragActionTypes.All)

Allows the control to accept a picture drop of a WebDragItem.

WebSDKUIControl.AcceptRawDataDrop

AcceptRawDataDrop(dragActionType As WebDragItem.DragActionTypes = WebDragItem.DragActionTypes.All)

Allows the control to accept a raw data drop of a WebDragItem.

WebSDKUIControl.AcceptTextDrop

AcceptTextDrop(dragActionType As WebDragItem.DragActionTypes = WebDragItem.DragActionTypes.All)

Allows the control to accept a picture drop of a WebDragItem.

WebSDKUIControl.AllowPictureDrag

AllowPictureDrag(allowedDragActionTypes As WebDragItem.DragActionTypes)

Allows the control to be dragged as a picture.

WebSDKUIControl.AllowRawDataDrag

AllowRawDataDrag(dragActionType As WebDragItem.DragActionTypes = WebDragItem.DragActionTypes.All)

Allows the control to be dragged as raw data.

WebSDKUIControl.AllowTextDrag

AllowTextDrag(dragActionType As WebDragItem.DragActionTypes = WebDragItem.DragActionTypes.All)

Allows the control to be dragged as text.

WebSDKUIControl.Close

Close

Removes the control from the page.

WebSDKUIControl.CSSClasses

CSSClasses As WebCSSClasses

Returns the instance of WebCSSClasses for this control allowing you to add CSS classes to and remove CSS classes from the control.

WebSDKUIControl.ExecuteJavaScript

ExecuteJavaScript(script As String)

Executes the JavaScript passed. The JavaScript passed can call a JavaScript function in a WebPageSource control.

The Xojo web framework uses EcmaScript 6 which is more strict than previous versions of JavaScript. For more details, see the EcmaScript 6 documentation.

This code in the Pressed event of a Button displays an alert using JavaScript:

Me.ExecuteJavaScript("alert('Hello!');")

This code will select the text in a WebTextField (or WebTextArea):

WebTextField1.ExecuteJavascript("document.getElementById('" + _
  WebTextField1.ControlID + "_inner').select();")

WebSDKUIControl.GoToURL

GoToURL(url As String, inNewWindow As Boolean = False)

Opens the passed url in place of the current web page or downloads a file. If inNewWindow is True, the browser is asked to open the url in a new window.

If the browser has popup windows disabled and inNewWindow is True, the method silently fails and the page is not shown.

If inNewWindow is False, the running web app is replaced with the specified url. If you want to display an external web site within your web app, use the WebHTMLViewer control.

Display a web site in a new popup window:

Me.GoToURL("http://www.wikipedia.org", True)

WebSDKUIControl.SetFocus

SetFocus

If the control is enabled, this method sets the focus to the WebUIControl.

This code checks for a required value when a button is pressed:

If UserNameField.Text.IsEmpty Then
  MessageBox("Please enter your UserName.")
  UserNameField.SetFocus
  Return
End If

WebSDKUIControl.Style

Style As WebStyle

Returns the WebStyle for the control.

Style(Assigns value As WebStyle)

Assigns the style to the control.

In the Pressed event of a WebButton, set the text to bold:

Var style As New WebStyle
style.Bold = True
Me.Style = style

WebSDKUIControl.UpdateBrowser

UpdateBrowser

Forces the current values of the control to be sent to the browser.

This method is useful when you are computing values in a loop and wish to update the browser immediately rather than wait until the current method ends.

This code iterates through a RowSet of database rows, updates a ProgressBar and then forces the updated ProgressBar to be sent to the browser via UpdateBrowser.

ProgressBar1.MaximumValue = SalesData.RowCount
For Each row As DatabaseRow in SalesData
  AnalyzeSales(row)
  ProgressBar1.Value = ProgressBar1.Value + 1
  ProgressBar1.UpdateBrowser
Next

WebSDKUIControl.UpdateControl

UpdateControl(sendImmediately As Boolean = False)

Similar to the UpdateBrowser method, this method also sets the internal flag which indicates to the framework that your control needs a refresh on the browser. When sendImmediately is False, any changes made are deferred until the event loop completes. When sendImmediately is True, the changes will be sent at that very moment.

Note

Calling this method with sendImmediately set to True will override the "deferred" option of any changes before it was called.

Event descriptions

WebSDKUIControl.Closed

Closed

The control has been removed from the browser either because the page has closed or the control's Close method was called.

WebSDKUIControl.ContextualMenuSelected

ContextualMenuSelected(hitItem As WebMenuItem)

Called when a contextual menu item is selected. This selected item is contained in hitItem.

This code populates a contextual menu in the Opening event of a WebToolbar:

Var menu As New WebMenuItem

menu.AddMenuItem("One")
menu.AddMenuItem("Two")
menu.AddMenuItem("Three")
Me.ContextualMenu = menu

The menu selection is then handled by the ContextualMenuSelected event when the user right-clicks on the control. For example, it can be of the form:

Select Case hitItem.Text
Case "One"
  MessageBox("One")
Case "Two"
  MessageBox("Two")
Case "Three"
  MessageBox("Three")
End Select

WebSDKUIControl.DrawControlInLayoutEditor

DrawControlInLayoutEditor(g As Graphics)

This event fires whenever your control needs to be refreshed in the IDE's layout editor.

For more information of how this works, see Drawing Your Control.

WebSDKUIControl.DropObject

DropObject(obj As WebDragItem, action As WebDragItem.DragActionTypes, x As Integer, y As Integer)

Called when a dragged item is over a control that can accept it. The dragged item is contained in obj and the type of drag is identified by action.

WebSDKUIControl.ExecuteEvent

ExecuteEvent(name As String, parameters As JSONItem) As Boolean

This event fires when an event is sent from the browser to the app using the triggerServerEvent JavaScript method. Return True if your control has handled the event.

WebSDKUIControl.HandleRequest

HandleRequest(request As WebRequest, response As WebResponse) As Boolean

This event fires in the same way as App.HandleURL does except that it is for requests that are only for the current control.

To trigger this event you will need to create a specially formed URL:

Var url As String = "https://www.yourdomain.com/sdk/" + Self.ControlID

See the documentation for WebApplication.HandleURL for usage.

WebSDKUIControl.Hidden

Hidden

The control is about to become no longer visible. This could be because the page is being closed, is being replaced as the foreground page by another page or because the control or a parent control's Visible property has been set to False.

Note

This event is equivalent to the DesktopWindow.Deactivated event in a desktop app.

WebSDKUIControl.JavaScriptClassName

JavaScriptClassName As String

This event fires when the control is first created to send the JavaScript constructor for your control to the browser.

WebSDKUIControl.Opening

Opening

The control has been created and the page is opening but has not been sent to the browser yet.

The Opening event handler can be used to initialize non-visual properties and settings for controls.

In most cases, you should use the Shown event to initialize controls.

WebSDKUIControl.Serialize

Serialize(js As JSONItem)

This event fires when the framework sends the first configuration to your control in the browser, whenever a property on WebControl is changed and whenever you call the Xojo UpdateBrowser method.

WebSDKUIControl.SessionCSSURLs

SessionCSSURLs(session As WebSession) As String()

This event fires each time a new session starts. You should return an array of URLs which point to any css stylesheets you need for your control to function. The Xojo framework will attempt to prevent duplicate URLs from being sent to the same session.

Note

Hint: One reason we supply the session object is so you can figure out whether or not items have already been delivered to a particular session.

WebSDKUIControl.SessionHead

SessionHead(session As WebSession) As String

This event fires each time a new session starts. You should return a String containing the items you wish to add to the <head> tag.

WebSDKUIControl.SessionJavascriptURLs

SessionJavascriptURLs(session As WebSession) As String()

This event fires each time a new session starts. You should return an array of URLs which point to any javascript you need for your control to function, whether it be a subclass of XojoControl or an external library. The Xojo framework will attempt to prevent duplicate URLs from being sent to the same session.

Note

One reason we supply the session object is so you can figure out whether or not items have already been delivered to a particular session.

WebSDKUIControl.Shown

Shown

The control has appeared on the currently displayed page. This could be because its parent page just finished loading, its parent page has come to the foreground or the control is now visible having been previously invisible because it or its parent control's Visible property has been set to True.

Use the Shown event for initializing your controls or doing anything that would interact with other controls or user interface elements on the web page instead of the Opening event.

Note

This event is the web equivalent to the DesktopWindow.Activated event.

This code in the Shown event of a WebListBox adds 2 rows with 3 columns:

Me.RemoveAllRows
Me.AddRow("Row 1", "Bob", "Roberts")
Me.AddRow("Row 2", "Barb", "Reynolds")

This example sets the text of a label:

If Session.LoggedIn Then
  Me.Text = "Welcome!"
Else
  Me.Text = "Welcome, " + Session.UserName
End If

Drawing Your Control

WebSDK Controls in 2020r1 and above have the ability to draw themselves in the layout editor using the same techniques that you might use to draw a control in the Paint event of a canvas. We developed a specialized XojoScript API 2 compatible Graphics context which allows you to draw just as you would in the Paint event of a canvas object. The difference here is that you also have access to the Properties and Constants of your class as well as being able to query the current Bootstrap theme.

For the purposes of drawing controls in the Layout Editor, you will need to implement the DrawControlInLayoutEditor event (you should implement it even if you're not using it, just so your end-users don't see the event). You can put just about any API 2 graphics drawing code into this event and have it render in the Layout editor. If the code you have placed in the event can't compile or runs into a runtime issue, an amber warning icon will be drawn on your control and the errors will be sent to the Messages panel.

Here's an example of how you would draw a red oval within the bounds of the control:

g.DrawingColor = &cFF0000
g.DrawOval(0, 0, g.Width, g.Height)

In addition to the standard drawing controls, there are also some methods for accessing the properties and constants in your control as well as getting values from the user's current Bootstrap theme file.

Property Methods

BooleanProperty(Name as String) as Boolean

Gets the current value of a Boolean property of your control.

ColorProperty(name As String) As Color

Gets the current value of a Color property of your control.

DoubleProperty(name As String) As Double

Gets the current value of a Double property of your control.

IntegerProperty(name As String) As Integer

Gets the current value of an Integer property of your control.

PictureProperty(name As String) As Picture

Gets the current value of a Picture property of your control.

StringProperty(name As String) As String

Gets the current value of a String property of your control.

Constant Methods

ConstantValue(name As String) As String

Gets the value of a constant in your control as a String.

PictureConstant(name As String) As Picture

Gets the value of a constant in your control as a Picture.

Color Methods

ColorGroup.NamedColor(name As String) As Color

When running on a platform that supports named colors (only macOS at the time of this writing), this method returns the named OS.

Note

Color names are case sensitive, so the macOS secondary label color should be "secondaryLabelColor".

TextColor As Color

Returns the current text color of the platform that the IDE is running on.

FillColor As Color

Returns the current fill color of the platform that the IDE is running on.

IsDarkMode As Boolean

Returns True if the system is running in dark mode (only macOS at the time of this writing).

Font Methods

FontCount As Integer

Returns the number of fonts available on the system.

FontAt(index As Integer) As String

Returns the name of the font at the specified index.

CSS Methods

CSSColorValue(selector as String, propertyName As String, fallbackColor As Color) As Color

Returns a Xojo color converted from whatever format was used in the CSS color definition. Automatically converts #RRGGBB, rgb(1, 0, 0) and rgba(1, 0, 0, 0.5) style colors.

CSSPixelValue(selector As String, propertyName As String, fallbackValue As Double) As Double

Returns a pixel value for a particular selector and property, making automatic adjustments for things that may be in units other than px. Useful for things that may be represented in millimeters, points or rems (rems is multiplied by the value of Body font-size).

CSSStringValue(selector As String, propertyName As String) As String

Returns the raw value of a particular selector and property.

Other Methods

DebugLog(msg As String)

Sends msg to the Messages pane.

Compatibility

Project Types

Web

Operating Systems

All

See also

WebUIControl parent class