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LightVisualElement

LightVisualElement is a lightweight element which is capable of displaying Text, Border and Image and can be easily customized. Here is a list of its properties allowing for fine tuning the element:

  • ShouldPaint: Indicates whether the element should be painted. Children visibility would not be affected.

  • CanFocus: Gets or sets value indicating whether an element can receive input focus.

  • DrawText, DrawFill, DrawBorder Gets or sets value indicating whether an element can receive input focus.

  • BorderBoxStyle: Defines the border rendering style – SingleBorder, FourBorders, OuterInnerBorders

  • BorderDrawMode: Defines drawing border corners – HorizontalOverVertical, LeftOverTop, RightOverTop, RightOverBotton, LeftOverBottom etc.

  • BorderWidth: Defines the width the border on each side

  • BorderLeftWidth, BorderLeftWidth, BorderRightWidth, BorderBottomWidth Defines the width of the border on each side independently

  • BorderGradientAngle: Defines the angle of the gradient the border uses as background.

  • BorderGradientStyle: Defines the gradient effects: Solid, Linear, Radial, Glass, OfficeGlass, Gel, and Vista.

  • BorderColor, BorderColor2, BorderColor3, BorderColor4 Defines the four colors used for making gradient border background

  • BorderInnerColor, BorderInnerColor2, BorderInnerColor3, BorderInnerColor4 Defines the four colors used for making the inner gradient border background

  • BackColor, BackColor2, BackColor3, BackColor4 Defines the four colors used the element’s gradient background

  • NumberOfColors: Defines how many colors will be used to make the background color. If the value is ‘1’ the other three colors are ignored

  • GradientStyle: Defines the gradient effects: Solid, Linear, Radial, Glass, OfficeGlass, Gel, and Vista.

  • GradientAngle: Gets or sets the angle of the background gradient

  • GradientPercentage: Defines how much of the available space the first gradient color will take

  • GradientPercentage2: Defines the space available for the the second gradient color

  • BackgroundImage: Gets or sets the BackgroundImage. This image fills up the entire element’s background

  • Image: Gets or sets the element’s image, the image can be resized inside the element.

  • ImageLayout: Specifies the position of the image on the control. None, Tile, Center, Stretch, Zoom

  • BackgroundImageLayout: Specifies the position of the BackgroundImage on the control. None, Tile, Center, Stretch, Zoom

  • ImageOpacity: Specifies the opacity of the set image

  • ImageAlignment, TextAlignment Specifies alignment of content on the drawing surface. TopLeft, TopCenter, TopRight, MiddleLeft, MiddleCenter, MiddleRight, BottomLeft, BottomCenter, BottomRight

  • TextImageRelation: Specifies the position of the text and image relative to each other on a control. Overlay, ImageBeforeText, TextBeforeImage, ImageAboveText, TextAboveImage

  • ShowHorizontalLine, ShowHorizontalLineColor, ShowHorizontalLineWidth These properties allow you to modify a horizontal line over the element

  • PaintTextFormat: An object which Encapsulates text layout information (such as alignment, orientation and tab stops) display manipulations (such as ellipsis insertion and national digit substitution) and OpenType features

  • DisableHTMLRendering: Gets or sets the value indicating whether html tags will be rendered.

  • TextBlock: An object which contains the text and its styling.

  • BorderLeftColor, BorderTopColor, BorderRightColor, BorderBottomColor, BorderLeftShadowColor, BorderTopShadowColor, BorderRightShadowColor, BorderBottomShadowColor Defines border colors and shadows

  • ClipText: Determines whether text will be clipped within the calculated text paint rectangle.

  • Layout: Gets the LayoutManagerPart which is responsible for the layout. Use this property to set the margins of left, right parts separately.

  • ImageTransparentColor: Transparent color to be used for the image.

  • BorderDashStyle: Specifies the style of dashed lines drawn with a border

  • EnableImageTransparency: Gets or sets a value indicating whether image transparency is supported.

  • Shadow: Gets or Sets the ShadowSettings

  • AutoEllipsis: Determines whether character trimming will be automatically applied to the element if text cannot be fitted within the available space.

  • UseMnemonic: Determines whether ampersand character will be treated as mnemonic or not.

  • TextWrap: Determines whether text wrap is enabled.

  • MeasureTrailingSpaces: Indicates whether the trailing white spaces will be calculated by the layout logic

  • TextParams: Gets the TextParams object which defines some text settings

The following example will show you how to make a simple image gallery with three LightVisualElements inside a DockLayoutPanel.

tpf-primitives-lightvisualelement 001

Creating a simple control with LightVisualElements

public class MyLightVisualElement : RadElement
{
    private DockLayoutPanel mainPanel;
    private LightVisualElement leftButtonElement;
    private LightVisualElement rightButtonElement;
    private LightVisualElement currentImageElement;
    private Image[] images;
    protected override void CreateChildElements()
    {
        this.mainPanel = new DockLayoutPanel();
        this.mainPanel.LastChildFill = true;
        this.Children.Add(this.mainPanel);
        this.leftButtonElement = new LightVisualElement();
        this.leftButtonElement.Text = "<--";
        this.leftButtonElement.DrawBorder = true;
        this.mainPanel.Children.Add(this.leftButtonElement);
        DockLayoutPanel.SetDock(this.leftButtonElement, Telerik.WinControls.Layouts.Dock.Left);
        this.leftButtonElement.Click += leftButtonElement_Click;
        this.rightButtonElement = new LightVisualElement();
        this.rightButtonElement.Text = "-->";
        this.rightButtonElement.DrawFill = true;
        this.rightButtonElement.BackColor = Color.Green;
        this.mainPanel.Children.Add(this.rightButtonElement);
        DockLayoutPanel.SetDock(this.rightButtonElement, Telerik.WinControls.Layouts.Dock.Right);
        this.rightButtonElement.Click += rightButtonElement_Click;
        this.currentImageElement = new LightVisualElement();
        this.mainPanel.Children.Add(this.currentImageElement);
        string imageFilesDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyPictures);
        string[] imageFiles = Directory.GetFiles(imageFilesDirectory, "*.jpg");
        this.images = new Image[imageFiles.Length];
        for (int i = 0; i < imageFiles.Length; i++)
        {
            this.images[i] = new Bitmap(Image.FromFile(imageFiles[i]), new Size(300, 100));
        }
        if (this.images.Length >= 0)
        {
            this.currentImageElement.Image = this.images[0];
        }
        base.CreateChildElements();
    }
    private void rightButtonElement_Click(object sender, EventArgs e)
    {
        int currentImageIndex = Array.IndexOf(this.images, this.currentImageElement.Image);
        if (++currentImageIndex <= this.images.Length - 1)
        {
            this.currentImageElement.Image = this.images[currentImageIndex];
        }
    }
    private void leftButtonElement_Click(object sender, EventArgs e)
    {
        int currentImageIndex = Array.IndexOf(this.images, this.currentImageElement.Image);
        if (--currentImageIndex >= 0)
        {
            this.currentImageElement.Image = this.images[currentImageIndex];
        }
    }
}

Public Class MyLightVisualElement
    Inherits RadElement
    Private mainPanel As DockLayoutPanel
    Private leftButtonElement As LightVisualElement
    Private rightButtonElement As LightVisualElement
    Private currentImageElement As LightVisualElement
    Private images() As System.Drawing.Image
    Protected Overrides Sub CreateChildElements()
        Me.mainPanel = New DockLayoutPanel()
        Me.mainPanel.LastChildFill = True
        Me.Children.Add(Me.mainPanel)
        Me.leftButtonElement = New LightVisualElement()
        Me.leftButtonElement.Text = "<--"
        Me.leftButtonElement.DrawBorder = True
        Me.mainPanel.Children.Add(Me.leftButtonElement)
        DockLayoutPanel.SetDock(Me.leftButtonElement, Telerik.WinControls.Layouts.Dock.Left)
        AddHandler Me.leftButtonElement.Click, AddressOf leftButtonElement_Click
        Me.rightButtonElement = New LightVisualElement()
        Me.rightButtonElement.Text = "-->"
        Me.rightButtonElement.DrawFill = True
        Me.rightButtonElement.BackColor = System.Drawing.Color.Green
        Me.mainPanel.Children.Add(Me.rightButtonElement)
        DockLayoutPanel.SetDock(Me.rightButtonElement, Telerik.WinControls.Layouts.Dock.Right)
        AddHandler Me.rightButtonElement.Click, AddressOf rightButtonElement_Click
        Me.currentImageElement = New LightVisualElement()
        Me.mainPanel.Children.Add(Me.currentImageElement)
        Dim imageFilesDirectory As String = Environment.GetFolderPath(Environment.SpecialFolder.MyPictures)
        Dim imageFiles As String() = Directory.GetFiles(imageFilesDirectory, "*.jpg")
        ReDim images(imageFiles.Length - 1)
        For i As Integer = 0 To imageFiles.Length - 1
            Me.images(i) = New System.Drawing.Bitmap(System.Drawing.Image.FromFile(imageFiles(i)), New System.Drawing.Size(300, 100))
        Next
        If Me.images.Length >= 0 Then
            Me.currentImageElement.Image = Me.images(0)
        End If
        MyBase.CreateChildElements()
    End Sub
    Private Sub rightButtonElement_Click(sender As Object, e As EventArgs)
        Dim currentImageIndex As Integer = Array.IndexOf(Me.images, Me.currentImageElement.Image)
        If System.Threading.Interlocked.Increment(currentImageIndex) <= Me.images.Length - 1 Then
            Me.currentImageElement.Image = Me.images(currentImageIndex)
        End If
    End Sub
    Private Sub leftButtonElement_Click(sender As Object, e As EventArgs)
        Dim currentImageIndex As Integer = Array.IndexOf(Me.images, Me.currentImageElement.Image)
        If System.Threading.Interlocked.Decrement(currentImageIndex) >= 0 Then
            Me.currentImageElement.Image = Me.images(currentImageIndex)
        End If
    End Sub
End Class

See Also