Class
DesktopChart
Description
Displays data you provide in chart form of various types.
Properties
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Methods
Name |
Parameters |
Returns |
Shared |
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FileType As String |
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Type As String |
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dataset As ChartDataset |
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index As Integer, Dataset As ChartDataset |
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Datasets() As ChartDataset |
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name As String |
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names() As String |
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index As Integer |
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index As Integer |
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x As Integer, y As Integer, width As Integer, height As Integer, immediately As Boolean = False |
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index As Integer |
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index As Integer |
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dx As Integer, dy As Integer, x As Integer = 0, y As Integer = 0, width As Integer = -10000, height As Integer = -10000, moveControls As Boolean = True |
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Events
Name |
Parameters |
Returns |
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base As DesktopMenuItem, x As Integer, y As Integer |
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selectedItem As DesktopMenuItem |
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obj As DragItem, Action As DragItem.Types |
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obj As DragItem, Action As DragItem.Types |
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x As Integer, y As Integer, obj As DragItem, Action As DragItem.Types |
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Obj As DragItem, Action As DragItem.Types |
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DataSet As ChartDataSet |
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Key As String |
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Key As String |
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dataset As ChartDataset, index As Integer |
Enumerations
DesktopChart.Modes
Modes
The various types of charts available.
Enum |
|---|
Bar |
Bubble |
Doughnut |
Line |
Pie |
PolarArea |
Radar |
Scatter |
Stacked |
Property descriptions
Desktopchart.Active
Active As Boolean
Indicates whether the DesktopChart is active.
This property is read-only.
Active is False when the control's window is not in the foreground. When a DesktopWindow is deactivated, its controls are automatically deactivated unless AllowAutoDeactivate is set to False.
DesktopChart.AllowAutoDeactivate
AllowAutoDeactivate As Boolean
Determines whether the control should be deactivated (on macOS) when the parent window is deactivated. The default is True.
DesktopChart.AllowFocus
AllowFocus As Boolean
If True, the DesktopChart will be included in the Tab order and can accept the focus. The FocusReceived and FocusLost events are called at the appropriate times.
This code enables the AllowFocus property. It is in the Opening event of the control.
Me.AllowFocus = True
DesktopChart.AllowFocusRing
AllowFocusRing As Boolean
If True, the DesktopChart indicates that it has the focus with a ring around its border; if False, the appearance of the object does not change when it has the focus.
Setting this property to True has no effect on Windows or Linux. The default is True.
This code turns AllowFocusRing off.
Me.AllowFocusRing = False
DesktopChart.AllowPopover
AllowPopover As Boolean
If True, a popover will be displayed when the user positions the mouse over items that have additional information.
The default value is True.
DesktopChart.AllowTabs
AllowTabs As Boolean
If True and AllowFocus is True, then pressing Tab triggers the KeyDown event for processing. The default is False.
If False, pressing the Tab key does not trigger the KeyDown event; pressing Tab triggers the FocusLost Event and selects the next object in the window that can accept the focus.
The following turns on AllowTabs.
Me.AllowTabs = True
DesktopChart.AllowTabStop
AllowTabStop As Boolean
If True, the control is in the Tab Order and accepts the focus when the user tabs into it. The default is True. If False, the user cannot tab into it to give it the focus. However, the control can gain the focus by other means, such as the user's clicking on it or by setting the focus in code.
This example removes the control from the Tab Order:
Me.AllowTabStop = False
DesktopChart.AutoCalculateYAxis
AutoCalculateYAxis As Boolean
If True, the Y axis for Line and Bar charts will start at 0.
This property is True by default.
DesktopChart.Backdrop
Backdrop As Picture
The passed Picture that will automatically be drawn behind the chart data.
The following code assigns a jpg image to the Backdrop. The image has been added to the project. The code is in the Opening event.
Me.BackDrop = HouseImage
DesktopChart.BackgroundColor
BackgroundColor As ColorGroup
The color of the background of the chart.
DesktopChart.DatasetCount
DatasetCount As Integer
The number of datasets that have been added to the chart.
This property is read-only.
DesktopChart.DatasetLastIndex
DatasetLastIndex As Integer
The index of last dataset added to the chart.
This property is read-only.
DesktopChart.Enabled
Enabled As Boolean
When True the control is drawn enabled and responds to user action. When False, the control appears as disabled and does not respond to user actions.
DesktopChart.FontName
FontName As String
Name of the font used to display the text content.
You can enter any font that is installed on the computer or the names of the two metafonts, "System" and "SmallSystem".
The System font is the font used by the system software as its default font. Different operating systems use different default fonts. If the system software supports both a large and small System font, you can also specify the "SmallSystem" font as your FontName.
On macOS, "SmallSystem" specifies the OS's smaller system font and may make the control smaller in size as well. On Windows and Linux, "SmallSystem" is the same as "System".
This code sets the FontName property.
Me.FontName = "Helvetica"
DesktopChart.FontSize
FontSize As Double
Point size of the font used to display the caption.
If you enter zero as the FontSize, your app will use the font size that works best for the platform on which it is running.
This code sets the font size to 16 points.
Me.FontSize = 16
DesktopChart.Format
Format As String
Used to format axis values.
It uses the same formatting conventions as the Format function.
DesktopChart.GridColor
GridColor As ColorGroup
The color of the chart's grid.
DesktopChart.Handle
Handle As Ptr
Returns a handle to the control.
This property is read-only.
For interfacing with Mac APIs using Declares, DesktopControl.Handle returns NSViews (except for DesktopToolbar).
On Windows returns the HWND of the control.
On Linux it returns a GtkWidget.
The following gets a handle to the control.
Var p As Ptr = Me.Handle
DesktopChart.HasLegend
HasLegend As Boolean
If True, the chart's legend will be displayed.
DesktopChart.Height
Height As Integer
The height (in points) of the control.
DesktopChart.Index
Index As Integer
If the control is used in a control set, this specifies the control's index in the set.
This property is read-only.
DesktopChart.IsGridVisible
IsGridVisible As Boolean
Determines if the grid will be drawn or not.
DesktopChart.IsYAxisVisible
IsYAxisVisible As Boolean
Determines if the Y axis will be drawn or not.
DesktopChart.IsXAxisVisible
IsXAxisVisible As Boolean
Determines if the X axis will be drawn or not.
DesktopChart.LabelCount
LabelCount As Integer
The number of labels in the chart.
This property is read-only.
DesktopChart.LabelLastIndex
LabelLastIndex As Integer
The index of last label added to the chart.
This property is read-only.
DesktopChart.Left
Left As Integer
The position of the left side of the control in pixels, relative to the window.
DesktopChart.LegendColor
TextColor As ColorGroup
Gets or sets the color of the legend. The default value is black.
The following example sets the LegendColor.
Me.LegendColor = Color.Red
DesktopChart.LegendFontName
TitleFontName As String
Name of the font used to display the chart legend.
You can enter any font that is installed on the computer or the names of the two metafonts, "System" and "SmallSystem".
The System font is the font used by the system software as its default font. Different operating systems use different default fonts. If the system software supports both a large and small System font, you can also specify the "SmallSystem" font as your FontName.
On macOS, "SmallSystem" specifies the OS's smaller system font and may make the control smaller in size as well. On Windows and Linux, "SmallSystem" is the same as "System".
This code sets the FontName property.
Me.LegendFontName = "Helvetica"
DesktopChart.LegendFontSize
LegendFontSize As Double
Point size of the font used to display the legend.
If you enter zero as the FontSize, your app will use the font size that works best for the platform on which it is running.
This code sets the font size to 16 points.
Me.LegendFontSize = 16
DesktopChart.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 window.
This property is read-only.
DesktopChart.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 window.
This property is read-only.
DesktopChart.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 window.
This property is read-only.
DesktopChart.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 window.
This property is read-only.
DesktopChart.Mode
Mode As Modes
Indicates the type of chart the control is currently displaying.
Labels are required for a Bar chart to draw.
This example checks the mode of the chart:
If Chart1.Mode = DesktopChart.Modes.Bar then
Chart1.Title = "Sales Bar Chart"
End If
DesktopChart.MouseCursor
MouseCursor As MouseCursor
The cursor to be displayed while the mouse is within the control and both the DesktopApplication and DesktopWindow class's MouseCursor properties are Nil.
If the DesktopApplication class's MouseCursor property is not Nil or the DesktopWindow's MouseCursor property is not Nil, then any control's MouseCursor property is ignored. You can use a cursor stored in the Cursors module. On Macintosh, you can also obtain a MouseCursor from a resource file.
This line in the Opening event of the control sets the default cursor to the finger pointer.
Me.MouseCursor = System.Cursors.FingerPointer
DesktopChart.Name
Name As String
The name of the control.
This property is read-only.
DesktopChart.PanelIndex
PanelIndex As Integer
If the control has been placed on a DesktopTabPanel or DesktopPagePanel 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 DesktopTabPanel or DesktopPagePanel control, it returns the panel number. If the control is not on a DesktopPagePanel or DesktopTabPanel, 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 DesktopPagePanel.
This code displays the panel index of the control that is on the page.
MessageBox(Me.SelectedPanelIndex.ToString)
DesktopChart.Parent
Parent As Object
Used to get the control's parent control or page. If the parent control is a DesktopContainer, then it returns the DesktopContainer. If it is on a DesktopWindow, it returns the DesktopWindow.
This property is read-only.
DesktopChart.PopoverBackgroundColor
PopoverBackgroundColor As ColorGroup
The background color of the chart's popover.
DesktopChart.PopoverTextColor
PopoverTextColor As ColorGroup
The color of text in the chart's popover.
DesktopChart.ScaleFactor
ScaleFactor As Double
The scale factor used when converting user space coordinates to backing store coordinates for the DesktopChart.
DesktopChart.Scope
Scope As Integer
Used to determine whether access to the control is Public (0) or Private (2). The default is Public.
This property is read-only.
Note
This is a designtime-only property and thus can only be set in the Inspector and is not accessible via code.
If the Scope of a control is set to Private, it cannot be accessed from outside its parent window.
DesktopChart.TabIndex
TabIndex As Integer
The control's position in the Tab Order. The control with a TabIndex of 0 is the first control to get the focus when the window opens.
This example sets the control's TabIndex.
Me.TabIndex = 2
DesktopChart.TitleColor
TitleColor As ColorGroup
Gets or sets the color of the title. The default value is black.
The following example sets the TitleColor.
Me.TitleColor = Color.Red
DesktopChart.TextColor
TextColor As ColorGroup
Gets or sets the color of the text. The default value is black.
The following example sets the TextColor.
Me.TextColor = Color.Red
DesktopChart.Title
Title As String
The title of the chart.
DesktopChart.TitleFontName
TitleFontName As String
Name of the font used to display the chart title.
You can enter any font that is installed on the computer or the names of the two metafonts, "System" and "SmallSystem".
The System font is the font used by the system software as its default font. Different operating systems use different default fonts. If the system software supports both a large and small System font, you can also specify the "SmallSystem" font as your FontName.
On macOS, "SmallSystem" specifies the OS's smaller system font and may make the control smaller in size as well. On Windows and Linux, "SmallSystem" is the same as "System".
This code sets the FontName property.
Me.TitleFontName = "Helvetica"
DesktopChart.TitleFontSize
TitleFontSize As Double
Point size of the font used to display the title.
If you enter zero as the FontSize, your app will use the font size that works best for the platform on which it is running.
This code sets the font size to 16 points.
Me.TitleFontSize = 16
DesktopChart.Tooltip
Tooltip As String
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 Opening event of a Button sets the tooltip:
Me.Tooltip = "Save changes"
DesktopChart.Top
Top As Integer
The top of the control in local coordinates relative to the window.
DesktopChart.Transparent
Transparent As Boolean
Determines whether the control is transparent on Windows. The default is False. Has no effect on macOS or Linux.
Transparent controls draw more slowly and use more memory in order to cache the background. Unless you absolutely require transparency, leave this set to False.
For projects that were created prior to 2018r1, this property defaults to True to emulate previous behavior. Consider changing it to False to improve performance if you do not require transparency.
DesktopChart.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
DesktopChart.Width
Width As Integer
The width (in points) of the control.
This code in the Shown event handler increases the size of the control:
Me.Width = Me.Width + 50
DesktopChart.Window
Window As DesktopWindow
The control's parent window.
This property is read-only.
This code gets the parent window's Title property.
MessageBox(Me.Window.Title)
Method descriptions
DesktopChart.AcceptFileDrop
AcceptFileDrop(FileType As String)
Permits documents of type FileType to be dropped on the control. FileType must be a file type that you defined in via the FileType class or the File Type Sets Editor.
This code in the Opening event makes it possible for the user to drop either a picture or a file that is a jpeg image. The File Type Sets editor was used to define the “image/jpeg” file type. It is one of the “Common File Types” that is available in the editor.
Me.AcceptPictureDrop
Me.AcceptFileDrop("image/jpeg")
To restrict file drops to just folders (and not files), you can put this code in the DragEnter event:
If Not obj.FolderItem.IsFolder Then Return True
DesktopChart.AcceptPictureDrop
AcceptPictureDrop
Permits pictures to be dropped on the control.
If a control should accept pictures in a drag and drop, then AcceptPictureDrop needs to be called prior to the drop. Typically, it is in the Opening event of the control itself. For example, the line:
Me.AcceptPictureDrop
in the Opening event of the control that will receive the dragged pictures is needed. When the picture is dropped, the DropObject event is called and this is where you will put your code to handle the drop.
Opening Event:
Me.AcceptPictureDrop
DropObject Event:
If obj.PictureAvailable Then
Me.Backdrop = obj.Picture
End If
DesktopChart.AcceptRawDataDrop
AcceptRawDataDrop(Type As String)
Permits data (of the Type specified) to be dropped on the control.
The following specfies a generic file type defined in the File Type Sets editor.
Me.AcceptRawDataDrop("????")
DesktopChart.AcceptTextDrop
AcceptTextDrop
Permits text to be dropped on the control.
This line in the Opening event of a control that can accept dragged text.
Me.AcceptTextDrop
DesktopChart.AddDataset
AddDataset(dataset As ChartDataset)
Adds the dataset to the chart. Incompatible datasets are ignored.
DesktopChart.AddDatasetAt
AddDatasetAt(index As Integer, dataset As ChartDataset)
Adds the dataset to the chart at the index passed. Incompatible datasets are ignored.
DesktopChart.AddDatasets
AddDatasets(datasets() As ChartDataset)
Adds the array of datasets to the chart.
DesktopChart.AddLabel
AddLabel(name As String)
Adds the label to the chart.
DesktopChart.AddLabelAt
AddLabelAt(index As String, name As String)
Adds the label to the chart at the index passed.
DesktopChart.AddLabels
AddLabels(names() As String)
Adds the array of labels to the chart.
DesktopChart.Close
Close
Closes the control.
DesktopChart.DatasetAt
DatasetAt(index As Integer) As ChartDataset
Returns the ChartDataset at the index passed.
DesktopChart.DataSets
DataSets() As Iterable
Allows iterating through all data sets.
DesktopChart.DrawInto
DrawInto(g As Graphics, x As Integer, y As Integer)
Draws the contents of the control into the specified Graphics context. The parameters x and y are the coordinates of the top, left corner.
Note
DrawInto will only work if the control is on a window or container.
This example draws the current control into the Graphics of a Picture and then displays it as the Backdrop of the DesktopChart:
Var p As New Picture(Me.Width, Me.Height)
Me.DrawInto(p.Graphics, 0, 0)
Chart1.Backdrop = p
DesktopChart.LabelAt
LabelAt(index As Integer) As String
Returns the label at the index passed.
DesktopChart.Labels
Labels() As Iterable
Allows iterating through all labels.
DesktopChart.Refresh
Refresh(immediately As Boolean = False)
Redraws the portion specified of the contents of the control the next time the OS redraws the control or immediately if True is passed.
If you are calling this so frequently that you experience a slowdown in your code, pass True for the immediately parameter.
Calling this method causes the Render event to fire.
Refresh the entire area immediately:
Me.Refresh(True)
DesktopChart.Refresh
Refresh(x As Integer, y As Integer, width As Integer, height As Integer, immediately As Boolean = False)
Redraws the portion specified of the contents of the control the next time the OS redraws the control or immediately if True is passed.
Refresh a portion of the area the next time the OS redraws the control:
Me.Refresh(100, 150, 200, 300)
DesktopChart.RemoveAllDatasets
RemoveAllDatasets
Removes all datasets from the chart.
DesktopChart.RemoveAllLabels
RemoveAllLabels
Removes all labels from the chart.
DesktopChart.RemoveDatasetAt
RemoveDatasetAt(index As Integer)
Removes the ChartDataset at the index passed.
DesktopChart.RemoveLabelAt
RemoveLabelAt(index As Integer)
Removes the label at the index passed.
DesktopChart.Scroll
Scroll(dx As Integer, dy As Integer, x As Integer = 0, y As Integer = 0, width As Integer = -10000, height As Integer = -10000, moveControls As Boolean = True)
Scrolls the DesktopChart contents according to the passed parameters.
dx and dy are the number of points to scroll horizontally and vertically relative to the current position of the picture in the DesktopChart control. Positive values scroll right and down while negative values scroll left and up. The x, y, width, and height parameters specify the portion of the picture to be scrolled. If these are not passed, the entire picture will be scrolled. moveControls indicates whether controls positioned on top of the DesktopChart control should be scrolled as well. moveControls is True by default.
To use the Scroll method to scroll the contents of a DesktopChart control, you need to store the last scroll value for the axis you are scrolling so you can use this to calculate the amount to scroll. This can be done by adding properties to the window that contains the DesktopChart control or by creating a new class based on the DesktopChart control that contains properties to hold the last X scroll amount and last Y scroll amount.
If the moveControls parameter is True, any controls on top of the DesktopChart control will also be scrolled. This allows the implementation of a scrolling pane of controls.
The following example scrolls a picture that was added to the project. The properties XScroll and YScroll have been added to the window to hold the amounts the picture has been scrolled. The picture is scrolled 8 points at a time. In the Keydown event of the window, the following code calls the Scroll method whenever the Up, Down, Left, or Right arrow keys are pressed.
Const LeftArrow = 28
Const RightArrow = 29
Const UpArrow = 30
Const DownArrow = 31
Const ScrollUnit = 8 ' points
Select Case Key.Asc
Case LeftArrow
XScroll = XScroll + ScrollUnit
Chart1.Scroll(ScrollUnit, 0)
Case RightArrow
XScroll = XScroll - ScrollUnit
Chart1.Scroll(-ScrollUnit, 0)
Case UpArrow
YScroll = YScroll + ScrollUnit
Chart1.Scroll(0, ScrollUnit)
Case DownArrow
YScroll = YScroll - ScrollUnit
Chart1.Scroll(0, -ScrollUnit)
End Select
DesktopChart.SetFocus
SetFocus
Sets the focus to the DesktopChart control.
DesktopChart.ToPicture
ToPicture(width As Double = -1, height As Double = -1) As Picture
Returns the chart as a Picture at the size specified by the width and height parameters. If these parameters are not specified, the Picture is created using the dimensions of the chart.
Event descriptions
DesktopChart.Activated
Activated
The control is activated. In a single window interface, the Activate event fires when the parent window is activated. See the DesktopApplication and DesktopWindow Activate events.
This can be because the app is launched or a window belonging to another app is no longer frontmost (active). The Deactivate event fires when another window becomes active. In a single window interface, the Activate event fires when the window is activated, e.g., when the app first displays the window.
DesktopChart.Closing
Closing
The control is about to be removed from the window either because the window is closing or the control's Close method was called.
DesktopChart.ConstructContextualMenu
ConstructContextualMenu(base As DesktopMenuItem, x As Integer, y As Integer) As Boolean
This event is called when it is appropriate to display a contextual menu for the control.
This event handler is the recommended way to handle contextual menus because this event figures out whether the user has requested the contextual menu, regardless of how they did it. Depending on platform, it might be in the MouseUp or MouseDown event and it might be a right+click or by pressing the contextual menu key on the keyboard, for example.
Base is analogous to the menu bar for the contextual menu. Any items you add to Base will be shown as menu items. If you return False, the event is passed up the parent hierarchy.
If you return True, the contextual menu is displayed. The parameters x and y are the mouse locations. If the event was fired because of a non-mouse event, then x and y are both set to -1. See the example of a contextual menu in the following section.
The following ConstructContextualMenu event handler builds a menu with three menu items plus a submenu with three additional menu items.
' Add some items
base.AddMenu(New DesktopMenuItem("Test 1"))
base.AddMenu(New DesktopMenuItem("Test 2"))
base.AddMenu(New DesktopMenuItem("Test 3"))
' Add a Separator
base.AddMenu(New DesktopMenuItem(DesktopMenuItem.TextSeparator))
' Add a sub menu
Var submenu As New DesktopMenuItem("SubMenu")
submenu.AddMenu(New DesktopMenuItem("SubMenu Test 1"))
submenu.AddMenu(New DesktopMenuItem("SubMenu Test 2"))
submenu.AddMenu(New DesktopMenuItem("SubMenu Test 3"))
base.AddMenu(submenu)
' Add a Separator
base.AddMenu(New DesktopMenuItem(DesktopMenuItem.TextSeparator))
Return True
DesktopChart.ContextualMenuSelected
ContextualMenuSelected(selectedItem As DesktopMenuItem)
Called when selectedItem is chosen from a contextual menu.
This code populates a contextual menu in the Opening event of a Chart control:
Var menu As New DesktopMenuItem
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 selectedItem.Text
Case "One"
MessageBox("One")
Case "Two"
MessageBox("Two")
Case "Three"
MessageBox("Three")
End Select
DesktopChart.Deactivated
Deactivated
The DesktopChart is deactivated. See the DesktopApplication and DesktopWindow Deactivated events.
In a multiple window interface, the Deactivated event fires when the parent window is deactivated because another window has been brought to the front or a window belonging to another app becomes frontmost. In a single window app, the Deactivated event fires when a window belonging to another app becomes frontmost.
DesktopChart.DragEnter
DragEnter(obj As DragItem, Action As DragItem.Types) As Boolean
Fires when the passed DragItem enters the DesktopChart control.
Returns a Boolean. Return True from this event to prevent the drop from occurring.
The Action parameter specifies the type of drag action.
To restrict file drops to just folders (and not files), you can put this code in the DragEnter event:
If Not obj.FolderItem.IsFolder Then Return True
DesktopChart.DragExit
DragExit(obj As DragItem, Action As DragItem.Types)
Fires when the passed DragItem exits the DesktopChart control.
The Obj parameter is the item being dragged. The Action parameter specifies the type of drag action.
DesktopChart.DragOver
DragOver(x As Integer, y As Integer, obj As DragItem, Action As DragItem.Types) As Boolean
Fires when the DragItem is over the DesktopChart control.
The Obj parameter is the object being dragged. The coordinates x and y are relative to the DesktopChart. Returns a Boolean. Return True from this event to prevent the drop from occurring.
The Action parameter specifies the type of drag action, which is typically done by holding down a modifier key (Shift, Alt, Option, Command, etc.) while doing the drag.
DesktopChart.DropObject
DropObject(Obj As DragItem Action As DragItem.Types)
The item represented by Obj has been dropped on the control.
The Obj parameter is the object being dragged. The Action parameter specifies the type of drag action.
The following DropObject event handler can handle either a dropped picture or a dropped file. The type of file that it can handle needs to have been specified in a call to AcceptFileDrop prior to the drop, for example, in the Opening event.
If Obj.PictureAvailable Then
Me.Image = obj.Picture
ElseIf Obj.FolderItemAvailable Then
Me.Image = Picture.Open(obj.FolderItem)
End If
DesktopChart.Error
Error(DataSet As ChartDataSet)
The chart either has no room to display the data or is too small to draw the grid. The DataSet is the ChartDataSet assigned to the control.
DesktopChart.FocusLost
FocusLost
The control has lost the focus.
This property must be set to True for the control to be capable of getting then losing the focus.
Note
On macOS, controls other than text fields and lists will accept and lose focus only if the full keyboard access option is enabled in System Preferences/Keyboard.
DesktopChart.FocusReceived
FocusReceived
The control has received the focus and has a selection rectangle around it.
This property must be set to True for the control to be capable of getting the focus.
Note
On macOS, controls other than text fields and lists will accept focus only if the full keyboard access option is enabled in System Preferences/Keyboard.
DesktopChart.KeyDown
KeyDown(Key As String) As Boolean
The user has pressed the Key passed while the control has the focus.
How KeyDown works depends on the type of control.
Returning True means the key is intercepted, preventing the key from actually reaching the control at all. This would be useful if you want to override the behavior of the tab key for example. Returning False means the key reaches the control.
DesktopChart.KeyUp
KeyUp(Key As String)
Fires when the passed Key is released in the control that has the focus.
It is not guaranteed to be the same key that received the KeyDown event.
DesktopChart.MenuBarSelected
MenuBarSelected
Indicates that the control has the focus and a menu (not a menu item) has been selected by the user.
DesktopChart.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.
DesktopChart.Pressed
Pressed(dataset As ChartDataset, index As Integer)
The user pressed on a part of the chart that represents data from the dataset.
Compatibility
Desktop projects on all supported operating systems.
See also
DesktopCanvas parent class; ChartCircularDataset, ChartDataset, ChartLinearDataset and ChartScatterDatapoint classes.