命名空间 System.Windows.Forms.VisualStyles 公开 VisualStyleElement 表示视觉样式支持的 Windows 用户界面 (UI) 元素的对象。 本主题演示如何使用 VisualStyleRenderer 类来呈现 VisualStyleElement 表示“开始”菜单的 “注销 ”和“ 关闭 ”按钮。
呈现视觉样式元素
创建一个 VisualStyleRenderer 并将其设置为要绘制的元素。 请注意属性 Application.RenderWithVisualStyles 和 VisualStyleRenderer.IsElementDefined 方法的使用;如果禁用视觉样式或未定义元素,构造 VisualStyleRenderer 函数将引发异常。
private: VisualStyleRenderer^ renderer; VisualStyleElement^ element; public: CustomControl() { this->Location = Point(50, 50); this->Size = System::Drawing::Size(200, 200); this->BackColor = SystemColors::ActiveBorder; this->element = VisualStyleElement::StartPanel::LogOffButtons::Normal; if (Application::RenderWithVisualStyles && VisualStyleRenderer::IsElementDefined(element)) { renderer = gcnew VisualStyleRenderer(element); } }
private VisualStyleRenderer renderer = null; private readonly VisualStyleElement element = VisualStyleElement.StartPanel.LogOffButtons.Normal; public CustomControl() { this.Location = new Point(50, 50); this.Size = new Size(200, 200); this.BackColor = SystemColors.ActiveBorder; if (Application.RenderWithVisualStyles && VisualStyleRenderer.IsElementDefined(element)) { renderer = new VisualStyleRenderer(element); } }
Private renderer As VisualStyleRenderer = Nothing Private element As VisualStyleElement = _ VisualStyleElement.StartPanel.LogOffButtons.Normal Public Sub New() Me.Location = New Point(50, 50) Me.Size = New Size(200, 200) Me.BackColor = SystemColors.ActiveBorder If Application.RenderWithVisualStyles And _ VisualStyleRenderer.IsElementDefined(element) Then renderer = New VisualStyleRenderer(element) End If End Sub
DrawBackground调用该方法以呈现当前表示的VisualStyleRenderer元素。
protected: virtual void OnPaint(PaintEventArgs^ e) override { // Draw the element if the renderer has been set. if (renderer != nullptr) { renderer->DrawBackground(e->Graphics, this->ClientRectangle); } // Visual styles are disabled or the element is undefined, // so just draw a message. else { this->Text = "Visual styles are disabled."; TextRenderer::DrawText(e->Graphics, this->Text, this->Font, Point(0, 0), this->ForeColor); } }
protected override void OnPaint(PaintEventArgs e) { // Draw the element if the renderer has been set. if (renderer != null) { renderer.DrawBackground(e.Graphics, this.ClientRectangle); } // Visual styles are disabled or the element is undefined, // so just draw a message. else { this.Text = "Visual styles are disabled."; TextRenderer.DrawText(e.Graphics, this.Text, this.Font, new Point(0, 0), this.ForeColor); } }
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs) ' Draw the element if the renderer has been set. If (renderer IsNot Nothing) Then renderer.DrawBackground(e.Graphics, Me.ClientRectangle) ' Visual styles are disabled or the element is undefined, ' so just draw a message. Else Me.Text = "Visual styles are disabled." TextRenderer.DrawText(e.Graphics, Me.Text, Me.Font, _ New Point(0, 0), Me.ForeColor) End If End Sub
编译代码
此示例需要:
派生自类的 Control 自定义控件。
一个承载自定义控件的 Form。
对System、System.Drawing、System.Windows.Forms和System.Windows.Forms.VisualStyles命名空间的引用。