ZoomFactor Property (IEditingControl)

Gets or sets a value that indicates the current zoom ratio.

Syntax

Visual Basic (Declaration)
Visual Basic (Usage)
C#

Property ZoomFactor As Single

Dim instance As IEditingControl
Dim value As Single
 
instance.ZoomFactor = value
 
value = instance.ZoomFactor

float ZoomFactor {get; set;}

Property Value

A System.Single value that represents the current zoom ratio.

Remarks

This property is automatically set when a Cell enters edit mode within a GcMultiRow, or the GcMultiRow is zoomed while in edit mode.

Example

The following code example shows how to use this property in a custom editing control. This code example is part of a larger example provided for the IEditingControl class.

public class ListBoxEditingControl : ListBox, IEditingControl
    {
        public ListBoxEditingControl()
        {
            this.BorderStyle = BorderStyle.None;
        }

        private GcMultiRow _gcMultiRow;

        // MultiRow sets this property when beginning to edit. The Editing control uses this property.
        public GcMultiRow GcMultiRow
        {
            get
            {
                return _gcMultiRow;
            }
            set
            {
                _gcMultiRow = value;
            }
        }

        private int _rowIndex;

        // MultiRow sets this property when beginning to edit. The Editing control uses this property.
        public int RowIndex
        {
            get
            {
                return _rowIndex;
            }
            set
            {
                _rowIndex = value;
            }
        }

        // 1. When beginning to edit, MultiRow should initialize this property.
        // 2. When ending the edit, MultiRow uses this property value as the cell value.
        public object FormattedValue
        {
            get
            {
                return this.Text;
            }
            set
            {
                if (value == null)
                {
                    this.Text = string.Empty;
                }
                else
                {
                    this.Text = value.ToString();
                }
            }
        }
        
        // When the user presses Ctrl and wheel mouse wheel button, MultiRow is zoomed.
        // MultiRow changes this property value when zooming.
        // EditingControl should do something to fit the new zoom factor, for example, change the font.
        private float _zoomFactor;
        private Font _initializeFont = null;
        public float ZoomFactor
        {
            get
            {
                return _zoomFactor;
            }
            set
            {
                this._zoomFactor = value;

                if (_zoomFactor != 1 && _initializeFont != null)
                {
                    this.Font = new Font(_initializeFont.FontFamily, _initializeFont.Size * _zoomFactor);
                }
            }
        }

        public Cursor EditingPanelCursor
        {
            get 
            {
                return Cursors.Default;
            }
        }

        // The keys handled by the editing control.
        public bool WantsInputKey(Keys keyData)
        {
            // The editing control will handle up and down keys.
            if (keyData == Keys.Up || keyData == Keys.Down)
            {
                return true;
            }
            return false;
        }

        public void PrepareEditingControlForEdit(bool selectAll)
        {
            // Do some thing to prepare edit for editing control.
        }

        // Apply style.
        public void ApplyCellStyleToEditingControl(CellStyle cellStyle)
        {
            this.BackColor = Color.FromArgb(255, cellStyle.BackColor);
            this.ForeColor = Color.FromArgb(255, cellStyle.ForeColor);

            _initializeFont = cellStyle.Font;

            if (this._zoomFactor != 1)
            {
                this.Font = new Font(_initializeFont.FontFamily, _initializeFont.Size * _zoomFactor);
            }
        }

        // When the value has been edited, editing control should fire DirtyStateChanged event to notify MultiRow 
control.
        protected override void OnSelectedIndexChanged(EventArgs e)
        {
            base.OnSelectedIndexChanged(e);

            this.OnDirtyStateChanged(EventArgs.Empty);
        }

        protected virtual void OnDirtyStateChanged(EventArgs e)
        {
            if (this.DirtyStateChanged != null)
            {
                this.DirtyStateChanged(this, e);
            }
        }

        public event EventHandler DirtyStateChanged;
    }

VB.NET

Public Class ListBoxEditingControl
    Inherits ListBox
    Implements IEditingControl
    Public Sub New()
        Me.BorderStyle = BorderStyle.None
    End Sub

    Private _gcMultiRow As GcMultiRow

    ' MultiRow sets this property when beginning to edit. The Editing control uses this property.
    Public Property GcMultiRow() As GcMultiRow Implements IEditingControl.GcMultiRow
        Get
            Return _gcMultiRow
        End Get
        Set(ByVal value As GcMultiRow)
            _gcMultiRow = value
        End Set
    End Property

    Private _rowIndex As Integer

    ' MultiRow sets this property when beginning to edit. The Editing control uses this property.
    Public Property RowIndex() As Integer Implements IEditingControl.RowIndex
        Get
            Return _rowIndex
        End Get
        Set(ByVal value As Integer)
            _rowIndex = value
        End Set
    End Property

    ' 1. When beginning to edit, MultiRow should initialize this property.
    ' 2. When ending the edit, MultiRow uses this property value as the cell value.
    Public Property FormattedValue() As Object Implements IEditingControl.FormattedValue
        Get
            Return Me.Text
        End Get
        Set(ByVal value As Object)
            If value = Nothing Then
                Me.Text = String.Empty
            Else
                Me.Text = value.ToString()
            End If
        End Set
    End Property

    ' When the user presses Ctrl and wheel mouse wheel button, MultiRow is zoomed.
    ' MultiRow changes this property's value when zooming.
    ' EditingControl should do something to fit the new zoom factor, for example, change the font.
    Private _zoomFactor As Single
    Private _initializeFont As Font = Nothing
    Public Property ZoomFactor() As Single Implements IEditingControl.ZoomFactor
        Get
            Return _zoomFactor
        End Get
        Set(ByVal value As Single)
            Me._zoomFactor = value

            If _zoomFactor <> 1 AndAlso Not _initializeFont Is Nothing Then
                Me.Font = New Font(_initializeFont.FontFamily, _initializeFont.Size * _zoomFactor)
            End If
        End Set
    End Property

    Public ReadOnly Property EditingPanelCursor() As Cursor Implements IEditingControl.EditingPanelCursor
        Get
            Return Cursors.Default
        End Get
    End Property

    ' The keys handled by the editing control.
    Public Function WantsInputKey(ByVal keyData As Keys) As Boolean Implements 
IEditingControl.WantsInputKey
        ' The editing control will handle up and down keys.
        If keyData = Keys.Up OrElse keyData = Keys.Down Then
            Return True
        End If
        Return False
    End Function

    Public Sub PrepareEditingControlForEdit(ByVal selectAll As Boolean) Implements 
IEditingControl.PrepareEditingControlForEdit
        ' Do something to prepare for the editing control.
    End Sub

    ' Apply style.
    Public Sub ApplyCellStyleToEditingControl(ByVal cellStyle As CellStyle) Implements 
IEditingControl.ApplyCellStyleToEditingControl
        Me.BackColor = Color.FromArgb(255, cellStyle.BackColor)
        Me.ForeColor = Color.FromArgb(255, cellStyle.ForeColor)

        _initializeFont = cellStyle.Font

        If Me._zoomFactor <> 1 Then
            Me.Font = New Font(_initializeFont.FontFamily, _initializeFont.Size * _zoomFactor)
        End If
    End Sub

    ' When the value has been edited, editing control should fire DirtyStateChanged event to notify MultiRow 
control.
    Protected Overloads Overrides Sub OnSelectedIndexChanged(ByVal e As EventArgs)
        MyBase.OnSelectedIndexChanged(e)

        Me.OnDirtyStateChanged(EventArgs.Empty)
    End Sub

    Protected Overridable Sub OnDirtyStateChanged(ByVal e As EventArgs)
        RaiseEvent DirtyStateChanged(Me, e)
    End Sub

    Public Event DirtyStateChanged As EventHandler Implements IEditingControl.DirtyStateChanged
End Class

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

IEditingControl Interface
IEditingControl Members