TrackBarRenderer.IsSupported Properti

Definisi

Ruang nama:

System.Windows.Forms

Rakitan:

System.Windows.Forms.dll

Sumber:

TrackBarRenderer.cs

Mendapatkan nilai yang menunjukkan apakah TrackBarRenderer kelas dapat digunakan untuk menggambar bilah trek dengan gaya visual.

public:
 static property bool IsSupported { bool get(); };

public static bool IsSupported { get; }

static member IsSupported : bool

Public Shared ReadOnly Property IsSupported As Boolean

Nilai Properti

Boolean

true jika pengguna telah mengaktifkan gaya visual dalam sistem operasi dan gaya visual diterapkan ke area klien jendela aplikasi; jika tidak, false.

Contoh

Contoh kode berikut menggunakan IsSupported properti untuk menentukan apakah akan menggunakan TrackBarRenderer metode . Contoh kode ini adalah bagian dari contoh yang lebih besar yang disediakan untuk TrackBarRenderer kelas .

    // Draw the track bar.
protected:
    virtual void OnPaint(PaintEventArgs^ e) override
    {
        if (!TrackBarRenderer::IsSupported)
        {
            this->Parent->Text = "CustomTrackBar Disabled";
            return;
        }

        this->Parent->Text = "CustomTrackBar Enabled";
        TrackBarRenderer::DrawHorizontalTrack(e->Graphics,
            trackRectangle);
        TrackBarRenderer::DrawTopPointingThumb(e->Graphics,
            thumbRectangle, thumbState);
        TrackBarRenderer::DrawHorizontalTicks(e->Graphics,
            ticksRectangle, numberTicks, EdgeStyle::Raised);
    }

    // Determine whether the user has clicked the track bar thumb.
protected:
    virtual void OnMouseDown(MouseEventArgs^ e) override
    {
        if (!TrackBarRenderer::IsSupported)
        {
            return;
        }
        if (this->thumbRectangle.Contains(e->Location))
        {
            thumbClicked = true;
            thumbState = TrackBarThumbState::Pressed;
        }

        this->Invalidate();
    }

// Draw the track bar.
protected override void OnPaint(PaintEventArgs e)
{
    if (!TrackBarRenderer.IsSupported)
    {
        this.Parent.Text = "CustomTrackBar Disabled";
        return;
    }

    this.Parent.Text = "CustomTrackBar Enabled";
    TrackBarRenderer.DrawHorizontalTrack(e.Graphics,
        trackRectangle);
    TrackBarRenderer.DrawTopPointingThumb(e.Graphics,
        thumbRectangle, thumbState);
    TrackBarRenderer.DrawHorizontalTicks(e.Graphics,
        ticksRectangle, numberTicks, EdgeStyle.Raised);
}

// Determine whether the user has clicked the track bar thumb.
protected override void OnMouseDown(MouseEventArgs e)
{
    if (!TrackBarRenderer.IsSupported)
        return;

    if (this.thumbRectangle.Contains(e.Location))
    {
        thumbClicked = true;
        thumbState = TrackBarThumbState.Pressed;
    }

    this.Invalidate();
}

' Draw the track bar.
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
    If Not TrackBarRenderer.IsSupported Then
        Me.Parent.Text = "CustomTrackBar Disabled"
        Return
    End If

    Me.Parent.Text = "CustomTrackBar Enabled"
    TrackBarRenderer.DrawHorizontalTrack(e.Graphics, _
        trackRectangle)
    TrackBarRenderer.DrawTopPointingThumb(e.Graphics, _
        thumbRectangle, thumbState)
    TrackBarRenderer.DrawHorizontalTicks(e.Graphics, _
        ticksRectangle, numberTicks, EdgeStyle.Raised)
End Sub

' Determine whether the user has clicked the track bar thumb.
Protected Overrides Sub OnMouseDown(ByVal e As MouseEventArgs)
    If Not TrackBarRenderer.IsSupported Then
        Return
    End If
    If Me.thumbRectangle.Contains(e.Location) Then
        thumbClicked = True
        thumbState = TrackBarThumbState.Pressed
    End If

    Me.Invalidate()
End Sub

Keterangan

Jika properti ini adalah false, metode kelas ini akan melempar .InvalidOperationException

Lihat juga

• VisualStyleState