Bearbeiten

Freigeben über


ITransformProvider.Move(Double, Double) Method

Definition

Moves the control.

public:
 void Move(double x, double y);
public void Move (double x, double y);
abstract member Move : double * double -> unit
Public Sub Move (x As Double, y As Double)

Parameters

x
Double

Absolute screen coordinates of the left side of the control.

y
Double

Absolute screen coordinates of the top of the control.

Exceptions

If the CanMove property is false.

Examples

The following example shows one possible implementation of this method for a custom control that can be moved.

/// <summary>
/// Moves the provider to the specified position.
/// </summary>
/// <param name="x">The specified X screen coordinate.</param>
/// <param name="y">The specified Y screen coordinate</param>
void ITransformProvider.Move(double x, double y)
{
    int leftInt = (int)x;
    int topInt = (int)y;

    if (!((ITransformProvider)this).CanMove)
        throw new InvalidOperationException(
            "Operation cannot be performed.");

    // Move should never be allowed to place a control outside the 
    // bounds of its container; the control should always be accessible 
    // using the keyboard or mouse.
    // Use the bounds of the parent window to limit the placement 
    // of the custom control.
    int maxLeft = 10;
    int maxTop = 10;
    int maxRight =
        this.customControl.formWidth - this.customControl.Width - 10;
    int maxBottom =
        this.customControl.formHeight - this.customControl.Height - 10;

    if (leftInt < maxLeft)
        leftInt = 0;
    if (topInt < maxTop)
        topInt = 0;
    if (leftInt > maxRight)
        leftInt = maxRight;
    if (topInt > maxBottom)
        topInt = maxBottom;

    // Invoke control method on separate thread to avoid clashing with UI.
    // Use anonymous method for simplicity.
    this.customControl.Invoke(new MethodInvoker(delegate ()
    {
        this.customControl.Left = leftInt;
        this.customControl.Top = topInt;
    }));
}
''' <summary>
''' Moves the provider to the specified position.
''' </summary>
''' <param name="x">The specified X screen coordinate.</param>
''' <param name="y">The specified Y screen coordinate</param>
Private Sub Move(ByVal x As Double, ByVal y As Double) Implements ITransformProvider.Move
    Dim leftInt As Integer = CInt(x)
    Dim topInt As Integer = CInt(y)

    If Not(CType(Me, ITransformProvider)).CanMove Then
        Throw New InvalidOperationException("Operation cannot be performed.")
    End If

    ' Move should never be allowed to place a control outside the 
    ' bounds of its container; the control should always be accessible 
    ' using the keyboard or mouse.
    ' Use the bounds of the parent window to limit the placement 
    ' of the custom control.
    Dim maxLeft As Integer = 10
    Dim maxTop As Integer = 10
    Dim maxRight As Integer = Me.customControl.formWidth - Me.customControl.Width - 10
    Dim maxBottom As Integer = Me.customControl.formHeight - Me.customControl.Height - 10

    If leftInt < maxLeft Then
        leftInt = 0
    End If
    If topInt < maxTop Then
        topInt = 0
    End If
    If leftInt > maxRight Then
        leftInt = maxRight
    End If
    If topInt > maxBottom Then
        topInt = maxBottom
    End If

    ' Invoke control method on separate thread to avoid clashing with UI.
    ' Use anonymous method for simplicity.
    Me.customControl.Invoke(New MethodInvoker(Sub()
        Me.customControl.Left = leftInt
        Me.customControl.Top = topInt
    End Sub))
End Sub

Remarks

An object cannot be moved, resized, or rotated such that its resulting screen location would be completely outside the coordinates of its container and inaccessible to keyboard or mouse. For example, when a top-level window is moved completely off-screen or a child object is moved outside the boundaries of the container's viewport. In these cases the object is placed as close to the requested screen coordinates as possible with the top or left coordinates overridden to be within the container boundaries.

Applies to

See also