ComboBoxRenderer.IsSupported Property
Definition
Important
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Gets a value indicating whether the ComboBoxRenderer class can be used to draw a combo box with visual styles.
public:
static property bool IsSupported { bool get(); };
public static bool IsSupported { get; }
static member IsSupported : bool
Public Shared ReadOnly Property IsSupported As Boolean
Property Value
true
if the user has enabled visual styles in the operating system and visual styles are applied to the client area of application windows; otherwise, false
.
Examples
The following code example uses the IsSupported property to determine whether to use the ComboBoxRenderer methods. This code example is part of a larger example provided for the ComboBoxRenderer class.
// Draw the combo box in the current state.
protected:
virtual void OnPaint(PaintEventArgs^ e) override
{
Control::OnPaint(e);
if (!ComboBoxRenderer::IsSupported)
{
this->Parent->Text = "Visual Styles Disabled";
return;
}
this->Parent->Text = "CustomComboBox Enabled";
// Always draw the main text box and drop down arrow in their
// current states
ComboBoxRenderer::DrawTextBox(e->Graphics, topTextBoxRectangle,
this->Text, this->Font, textBoxState);
ComboBoxRenderer::DrawDropDownButton(e->Graphics, arrowRectangle,
arrowState);
// Only draw the bottom text box if the arrow has been clicked
if (isActivated)
{
ComboBoxRenderer::DrawTextBox(e->Graphics,
bottomTextBoxRectangle, bottomText, this->Font,
textBoxState);
}
}
// Draw the combo box in the current state.
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
if (!ComboBoxRenderer.IsSupported)
{
this.Parent.Text = "Visual Styles Disabled";
return;
}
this.Parent.Text = "CustomComboBox Enabled";
// Always draw the main text box and drop down arrow in their
// current states
ComboBoxRenderer.DrawTextBox(e.Graphics, topTextBoxRectangle,
this.Text, this.Font, textBoxState);
ComboBoxRenderer.DrawDropDownButton(e.Graphics, arrowRectangle,
arrowState);
// Only draw the bottom text box if the arrow has been clicked
if (isActivated)
{
ComboBoxRenderer.DrawTextBox(e.Graphics,
bottomTextBoxRectangle, bottomText, this.Font,
textBoxState);
}
}
' Draw the combo box in the current state.
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
MyBase.OnPaint(e)
If Not ComboBoxRenderer.IsSupported Then
Me.Parent.Text = "Visual Styles Disabled"
Return
End If
Me.Parent.Text = "CustomComboBox Enabled"
' Always draw the main text box and drop down arrow in their
' current states.
ComboBoxRenderer.DrawTextBox(e.Graphics, topTextBoxRectangle, _
Me.Text, Me.Font, textBoxState)
ComboBoxRenderer.DrawDropDownButton(e.Graphics, arrowRectangle, _
arrowState)
' Only draw the bottom text box if the arrow has been clicked.
If isActivated Then
ComboBoxRenderer.DrawTextBox(e.Graphics, _
bottomTextBoxRectangle, bottomText, Me.Font, textBoxState)
End If
End Sub
Remarks
If this property is false
, the DrawTextBox or DrawDropDownButton methods will throw an InvalidOperationException.
Applies to
See also
Feedback
https://aka.ms/ContentUserFeedback.
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