TrackBarRenderer Klasa

Definicja

Przestrzeń nazw:

System.Windows.Forms

Zestaw:

System.Windows.Forms.dll

Udostępnia metody używane do renderowania kontrolki paska śledzenia za pomocą stylów wizualnych. Klasa ta nie może być dziedziczona.

public ref class TrackBarRenderer sealed

public ref class TrackBarRenderer abstract sealed

public sealed class TrackBarRenderer

public static class TrackBarRenderer

type TrackBarRenderer = class

Public NotInheritable Class TrackBarRenderer

Public Class TrackBarRenderer

Dziedziczenie

Object

TrackBarRenderer

Przykłady

W poniższym przykładzie kodu pokazano, jak utworzyć niestandardową kontrolkę, która używa TrackBarRenderer metod do rysowania poziomego paska śledzenia, który reaguje na kliknięcia myszy.

#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>
#using <System.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::VisualStyles;

namespace TrackBarRendererSample
{
    ref class CustomTrackBar : public Control
    {
    private:
        int numberTicks;
        Rectangle trackRectangle;
        Rectangle ticksRectangle;
        Rectangle thumbRectangle;
        int currentTickPosition;
        float tickSpace;
        bool thumbClicked;
        TrackBarThumbState thumbState;

    public:
        CustomTrackBar(int ticks, System::Drawing::Size trackBarSize)
        {
            this->Location = Point(10, 10);
            this->Size = trackBarSize;
            this->numberTicks = ticks;
            this->BackColor = Color::DarkCyan;
            this->DoubleBuffered = true;
            numberTicks = 10;
            thumbState = TrackBarThumbState::Normal;

            // Calculate the initial sizes of the bar,
            // thumb and ticks.
            SetupTrackBar();
        }

        // Calculate the sizes of the bar, thumb, and ticks rectangle.
    private:
        void SetupTrackBar()
        {
            if (!TrackBarRenderer::IsSupported)
            {
                return;
            }

            Graphics^ g = this->CreateGraphics();

            // Calculate the size of the track bar.
            trackRectangle.X = ClientRectangle.X + 2;
            trackRectangle.Y = ClientRectangle.Y + 28;
            trackRectangle.Width = ClientRectangle.Width - 4;
            trackRectangle.Height = 4;

            // Calculate the size of the rectangle in which to
            // draw the ticks.
            ticksRectangle.X = trackRectangle.X + 4;
            ticksRectangle.Y = trackRectangle.Y - 8;
            ticksRectangle.Width = trackRectangle.Width - 8;
            ticksRectangle.Height = 4;

            tickSpace = ((float)ticksRectangle.Width - 1) /
                ((float)numberTicks - 1);

            // Calculate the size of the thumb.
            thumbRectangle.Size =
                TrackBarRenderer::GetTopPointingThumbSize(g,
                TrackBarThumbState::Normal);

            thumbRectangle.X = CurrentTickXCoordinate();
            thumbRectangle.Y = trackRectangle.Y - 8;
        }

    private:
        int CurrentTickXCoordinate()
        {
            if (tickSpace == 0)
            {
                return 0;
            }
            else
            {
                return ((int)Math::Round(tickSpace) *
                    currentTickPosition);
            }
        }

        // 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();
        }

        // Redraw the track bar thumb if the user has moved it.
    protected:
        virtual void OnMouseUp(MouseEventArgs^ e) override
        {
            if (!TrackBarRenderer::IsSupported)
            {
                return;
            }
            if (thumbClicked == true)
            {
                if (e->Location.X > trackRectangle.X &&
                    e->Location.X < (trackRectangle.X +
                    trackRectangle.Width - thumbRectangle.Width))
                {
                    thumbClicked = false;
                    thumbState = TrackBarThumbState::Hot;
                    this->Invalidate();
                }

                thumbClicked = false;
            }
        }

        // Track cursor movements.
    protected:
        virtual void OnMouseMove(MouseEventArgs^ e) override
        {
            if (!TrackBarRenderer::IsSupported)
            {
                return;
            }
            // The user is moving the thumb.
            if (thumbClicked == true)
            {
                // Track movements to the next tick to the right, if
                // the cursor has moved halfway to the next tick.
                if (currentTickPosition < numberTicks - 1 &&
                    e->Location.X > CurrentTickXCoordinate() +
                    (int)(tickSpace))
                {
                    currentTickPosition++;
                }

                // Track movements to the next tick to the left, if
                // cursor has moved halfway to the next tick.
                else if (currentTickPosition > 0 &&
                    e->Location.X < CurrentTickXCoordinate() -
                    (int)(tickSpace / 2))
                {
                    currentTickPosition--;
                }

                thumbRectangle.X = CurrentTickXCoordinate();
            }

            // The cursor is passing over the track.
            else
            {
                if (thumbRectangle.Contains(e->Location))
                {
                    thumbState = TrackBarThumbState::Hot;
                }
                else
                {
                    thumbState = TrackBarThumbState::Normal;
                }
            }

            Invalidate();
        }
    };

    ref class Form1 : public Form
    {
    public:
        Form1()
        {
            CustomTrackBar^ TrackBar1 = gcnew CustomTrackBar(19,
                System::Drawing::Size(300, 50));
            this->Width = 500;
            this->Controls->Add(TrackBar1);
        }
    };
}

[STAThread]
int main()
{
    // Note that the call to EnableVisualStyles below does
    // not affect whether TrackBarRenderer.IsSupported is true;
    // as long as visual styles are enabled by the operating system,
    // IsSupported is true.
    Application::EnableVisualStyles();
    Application::Run(gcnew TrackBarRendererSample::Form1());
    return 0;
}

using System;
using System.Drawing;
using System.Windows.Forms;
using System.Windows.Forms.VisualStyles;

namespace TrackBarRendererSample
{
    class Form1 : Form
    {
        public Form1()
        {
            CustomTrackBar TrackBar1 = new CustomTrackBar(19,
                new Size(300, 50));
            this.Width = 500;
            this.Controls.Add(TrackBar1);
        }

        [STAThread]
        static void Main()
        {
            // Note that the call to EnableVisualStyles below does
            // not affect whether TrackBarRenderer.IsSupported is true; 
            // as long as visual styles are enabled by the operating system, 
            // IsSupported is true.
            Application.EnableVisualStyles();
            Application.Run(new Form1());
        }
    }

    class CustomTrackBar : Control
    {
        private int numberTicks = 10;
        private Rectangle trackRectangle = new Rectangle();
        private Rectangle ticksRectangle = new Rectangle();
        private Rectangle thumbRectangle = new Rectangle();
        private int currentTickPosition = 0;
        private float tickSpace = 0;
        private bool thumbClicked = false;
        private TrackBarThumbState thumbState =
            TrackBarThumbState.Normal;

        public CustomTrackBar(int ticks, Size trackBarSize)
        {
            this.Location = new Point(10, 10);
            this.Size = trackBarSize;
            this.numberTicks = ticks;
            this.BackColor = Color.DarkCyan;
            this.DoubleBuffered = true;

            // Calculate the initial sizes of the bar, 
            // thumb and ticks.
            SetupTrackBar();
        }

        // Calculate the sizes of the bar, thumb, and ticks rectangle.
        private void SetupTrackBar()
        {
            if (!TrackBarRenderer.IsSupported)
                return;

            using (Graphics g = this.CreateGraphics())
            {
                // Calculate the size of the track bar.
                trackRectangle.X = ClientRectangle.X + 2;
                trackRectangle.Y = ClientRectangle.Y + 28;
                trackRectangle.Width = ClientRectangle.Width - 4;
                trackRectangle.Height = 4;

                // Calculate the size of the rectangle in which to 
                // draw the ticks.
                ticksRectangle.X = trackRectangle.X + 4;
                ticksRectangle.Y = trackRectangle.Y - 8;
                ticksRectangle.Width = trackRectangle.Width - 8;
                ticksRectangle.Height = 4;

                tickSpace = ((float)ticksRectangle.Width - 1) /
                    ((float)numberTicks - 1);

                // Calculate the size of the thumb.
                thumbRectangle.Size =
                    TrackBarRenderer.GetTopPointingThumbSize(g,
                    TrackBarThumbState.Normal);

                thumbRectangle.X = CurrentTickXCoordinate();
                thumbRectangle.Y = trackRectangle.Y - 8;
            }
        }

        private int CurrentTickXCoordinate()
        {
            if (tickSpace == 0)
            {
                return 0;
            }
            else
            {
                return ((int)Math.Round(tickSpace) *
                    currentTickPosition);
            }
        }

        // 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();
        }

        // Redraw the track bar thumb if the user has moved it.
        protected override void OnMouseUp(MouseEventArgs e)
        {
            if (!TrackBarRenderer.IsSupported)
                return;

            if (thumbClicked == true)
            {
                if (e.Location.X > trackRectangle.X &&
                    e.Location.X < (trackRectangle.X +
                    trackRectangle.Width - thumbRectangle.Width))
                {
                    thumbClicked = false;
                    thumbState = TrackBarThumbState.Hot;
                    this.Invalidate();
                }

                thumbClicked = false;
            }
        }

        // Track cursor movements.
        protected override void OnMouseMove(MouseEventArgs e)
        {
            if (!TrackBarRenderer.IsSupported)
                return;

            // The user is moving the thumb.
            if (thumbClicked == true)
            {
                // Track movements to the next tick to the right, if 
                // the cursor has moved halfway to the next tick.
                if (currentTickPosition < numberTicks - 1 &&
                    e.Location.X > CurrentTickXCoordinate() +
                    (int)(tickSpace))
                {
                    currentTickPosition++;
                }

                // Track movements to the next tick to the left, if 
                // cursor has moved halfway to the next tick.
                else if (currentTickPosition > 0 &&
                    e.Location.X < CurrentTickXCoordinate() -
                    (int)(tickSpace / 2))
                {
                    currentTickPosition--;
                }

                thumbRectangle.X = CurrentTickXCoordinate();
            }

            // The cursor is passing over the track.
            else
            {
                thumbState = thumbRectangle.Contains(e.Location) ?
                    TrackBarThumbState.Hot : TrackBarThumbState.Normal;
            }

            Invalidate();
        }
    }
}

Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.VisualStyles


Namespace TrackBarRendererSample

    Class Form1
        Inherits Form

        Public Sub New()
            Dim TrackBar1 As New CustomTrackBar(19, New Size(300, 50))
            Me.Width = 500
            Me.Controls.Add(TrackBar1)
        End Sub

        <STAThread()> _
        Shared Sub Main()
            ' Note that the call to EnableVisualStyles below does
            ' not affect whether TrackBarRenderer.IsSupported is true; 
            ' as long as visual styles are enabled by the operating system, 
            ' IsSupported is true.
            Application.EnableVisualStyles()
            Application.Run(New Form1())
        End Sub
    End Class

    Class CustomTrackBar
        Inherits Control
        Private numberTicks As Integer = 10
        Private trackRectangle As New Rectangle()
        Private ticksRectangle As New Rectangle()
        Private thumbRectangle As New Rectangle()
        Private currentTickPosition As Integer = 0
        Private tickSpace As Single = 0
        Private thumbClicked As Boolean = False
        Private thumbState As TrackBarThumbState = TrackBarThumbState.Normal

        Public Sub New(ByVal ticks As Integer, ByVal trackBarSize As Size)

            With Me
                .Location = New Point(10, 10)
                .Size = trackBarSize
                .numberTicks = ticks
                .BackColor = Color.DarkCyan
                .DoubleBuffered = True
            End With

            ' Calculate the initial sizes of the bar, 
            ' thumb and ticks.
            SetupTrackBar()
        End Sub

        ' Calculate the sizes of the bar, thumb, and ticks rectangle.
        Private Sub SetupTrackBar()
            If Not TrackBarRenderer.IsSupported Then
                Return
            End If
            Using g As Graphics = Me.CreateGraphics()
                ' Calculate the size of the track bar.
                trackRectangle.X = ClientRectangle.X + 2
                trackRectangle.Y = ClientRectangle.Y + 28
                trackRectangle.Width = ClientRectangle.Width - 4
                trackRectangle.Height = 4

                ' Calculate the size of the rectangle in which to 
                ' draw the ticks.
                ticksRectangle.X = trackRectangle.X + 4
                ticksRectangle.Y = trackRectangle.Y - 8
                ticksRectangle.Width = trackRectangle.Width - 8
                ticksRectangle.Height = 4

                tickSpace = (CSng(ticksRectangle.Width) - 1) / _
                    (CSng(numberTicks) - 1)

                ' Calculate the size of the thumb.
                thumbRectangle.Size = _
                    TrackBarRenderer.GetTopPointingThumbSize( _
                    g, TrackBarThumbState.Normal)

                thumbRectangle.X = CurrentTickXCoordinate()
                thumbRectangle.Y = trackRectangle.Y - 8
            End Using
        End Sub

        Private Function CurrentTickXCoordinate() As Integer
            If tickSpace = 0 Then
                Return 0
            Else
                Return CInt(Math.Round(tickSpace)) * currentTickPosition
            End If
        End Function

        ' 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

        ' Redraw the track bar thumb if the user has moved it.
        Protected Overrides Sub OnMouseUp(ByVal e As MouseEventArgs)
            If Not TrackBarRenderer.IsSupported Then
                Return
            End If
            If thumbClicked = True Then
                If e.Location.X > trackRectangle.X And _
                    e.Location.X < trackRectangle.X + _
                    trackRectangle.Width - thumbRectangle.Width Then

                    thumbClicked = False
                    thumbState = TrackBarThumbState.Hot
                    Me.Invalidate()
                End If
                thumbClicked = False
            End If
        End Sub

        ' Track cursor movements.
        Protected Overrides Sub OnMouseMove(ByVal e As MouseEventArgs)
            If Not TrackBarRenderer.IsSupported Then
                Return
            End If
            ' The user is moving the thumb.
            If thumbClicked = True Then

                ' Track movements to the next tick to the right, if the
                ' cursor has moved halfway to the next tick.
                If currentTickPosition < numberTicks - 1 And _
                    e.Location.X > CurrentTickXCoordinate() + _
                    CInt(tickSpace) Then
                    currentTickPosition += 1

                ' Track movements to the next tick to the left, if 
                ' the cursor has moved halfway to the next tick.
                Else
                    If currentTickPosition > 0 And _
                        e.Location.X < CurrentTickXCoordinate() - _
                        CInt(tickSpace / 2) Then
                        currentTickPosition -= 1
                    End If
                End If
                thumbRectangle.X = CurrentTickXCoordinate()

            ' The cursor is passing over the track.
            Else
                If thumbRectangle.Contains(e.Location) Then
                    thumbState = TrackBarThumbState.Hot
                Else
                    thumbState = TrackBarThumbState.Normal
                End If
            End If

            Invalidate()
        End Sub

    End Class
End Namespace

Uwagi

Klasa TrackBarRenderer udostępnia zestaw static metod, których można użyć do renderowania każdej części kontrolki paska śledzenia przy użyciu bieżącego stylu wizualnego systemu operacyjnego. Renderowanie kontrolki odwołuje się do rysowania interfejsu użytkownika kontrolki. Jest to przydatne, jeśli rysujesz niestandardową kontrolkę, która powinna mieć wygląd bieżącego stylu wizualizacji.

Jeśli style wizualne są włączone w systemie operacyjnym, a style wizualne są stosowane do obszaru klienta okien aplikacji, metody w tej klasie będą rysować pasek śledzenia z bieżącym stylem wizualizacji. W przeciwnym razie metody w tej klasie będą zgłaszać wartość InvalidOperationException. Aby określić, czy można użyć składowych IsSupported tej klasy, możesz sprawdzić wartość właściwości.

Ta klasa opakowuje funkcjonalność System.Windows.Forms.VisualStyles.VisualStyleRenderer elementu, który jest ustawiony na jeden z elementów uwidocznionych przez klasę System.Windows.Forms.VisualStyles.VisualStyleElement.TrackBar . Aby uzyskać więcej informacji, zobacz Renderowanie kontrolek za pomocą stylów wizualnych.

Właściwości

IsSupported

Pobiera wartość wskazującą, czy TrackBarRenderer klasa może służyć do rysowania paska śledzenia ze stylami wizualnymi.

Metody

DrawBottomPointingThumb(Graphics, Rectangle, TrackBarThumbState)	Rysuje suwak paska ścieżki w dół (znany również jako kciuk) ze stylami wizualnymi.
DrawHorizontalThumb(Graphics, Rectangle, TrackBarThumbState)	Rysuje suwak paska ścieżki poziomej (znany również jako kciuk) ze stylami wizualnymi.
DrawHorizontalTicks(Graphics, Rectangle, Int32, EdgeStyle)	Rysuje określoną liczbę poziomych pasków śledzenia ze stylami wizualnymi.
DrawHorizontalTrack(Graphics, Rectangle)	Rysuje ścieżkę dla poziomego paska śledzenia ze stylami wizualnymi.
DrawLeftPointingThumb(Graphics, Rectangle, TrackBarThumbState)	Rysuje lewy suwak paska śledzenia (znany również jako kciuk) ze stylami wizualnymi.
DrawRightPointingThumb(Graphics, Rectangle, TrackBarThumbState)	Rysuje suwak paska śledzenia wskazujący prawo (znany również jako kciuk) ze stylami wizualnymi.
DrawTopPointingThumb(Graphics, Rectangle, TrackBarThumbState)	Rysuje suwak paska ścieżki w górę (znany również jako kciuk) ze stylami wizualnymi.
DrawVerticalThumb(Graphics, Rectangle, TrackBarThumbState)	Rysuje pionowy suwak paska śledzenia (znany również jako kciuk) ze stylami wizualnymi.
DrawVerticalTicks(Graphics, Rectangle, Int32, EdgeStyle)	Rysuje określoną liczbę pionowych pasków pasków ścieżki ze stylami wizualnymi.
DrawVerticalTrack(Graphics, Rectangle)	Rysuje ścieżkę dla pionowego paska śledzenia ze stylami wizualnymi.
GetBottomPointingThumbSize(Graphics, TrackBarThumbState)	Zwraca rozmiar suwaka paska śledzenia (znanego również jako kciuk) w pikselach, który wskazuje w dół.
GetLeftPointingThumbSize(Graphics, TrackBarThumbState)	Zwraca rozmiar suwaka paska śledzenia (znanego również jako kciuk) w pikselach wskazujący lewą stronę.
GetRightPointingThumbSize(Graphics, TrackBarThumbState)	Zwraca rozmiar suwaka paska śledzenia (znanego również jako kciuk) w pikselach, który wskazuje na prawo.
GetTopPointingThumbSize(Graphics, TrackBarThumbState)	Zwraca rozmiar suwaka paska śledzenia (znanego również jako kciuk) w pikselach, który wskazuje w górę.

Zobacz też

• VisualStyleRenderer
• VisualStyleElement