ProgressBarRenderer Klas

Definitie

public ref class ProgressBarRenderer sealed

public sealed class ProgressBarRenderer

type ProgressBarRenderer = class

Public NotInheritable Class ProgressBarRenderer

Overname

Object

ProgressBarRenderer

Voorbeelden

In het volgende codevoorbeeld ziet u hoe u een aangepast besturingselement maakt dat gebruikmaakt van de DrawVerticalBar en DrawVerticalChunks methoden om een verticale voortgangsbalk te tekenen. Het besturingselement gebruikt een Timer om de voortgangsbalk opnieuw te tekenen met elke seconde een toegevoegd stuk. De SetupProgressBar methode gebruikt de ChunkThickness en ChunkSpaceThickness eigenschappen om de hoogte te berekenen van elke progressief grotere rechthoek die wordt getekend.

#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 ProgressBarRendererSample
{
    public ref class VerticalProgressBar : public Control
    {
    private:
        int numberChunksValue;
        int ticks;
        Timer^ progressTimer;
        array<Rectangle>^ progressBarRectangles;

    public:
        VerticalProgressBar() : Control()
        {
            this->Location = Point(10, 10);
            this->Width = 50;
            progressTimer = gcnew Timer();

            // The progress bar will update every second.
            progressTimer->Interval = 1000;
            progressTimer->Tick += gcnew EventHandler(this,
                &VerticalProgressBar::progressTimer_Tick);

            // This property also calls SetupProgressBar to initialize
            // the progress bar rectangles if styles are enabled.
            NumberChunks = 20;

            // Set the default height if visual styles are not enabled.
            if (!ProgressBarRenderer::IsSupported)
            {
                this->Height = 100;
            }
        }

        // Specify the number of progress bar chunks to base the height on.
    public:
        property int NumberChunks
        {
            int get()
            {
                return numberChunksValue;
            }

            void set(int value)
            {
                if (value <= 50 && value > 0)
                {
                    numberChunksValue = value;
                }
                else
                {
                    MessageBox::Show("Number of chunks must be between " +
                        "0 and 50; defaulting to 10");
                    numberChunksValue = 10;
                }

                // Recalculate the progress bar size, if visual styles
                // are active.
                if (ProgressBarRenderer::IsSupported)
                {
                    SetupProgressBar();
                }
            }
        }

        // Draw the progress bar in its normal state.
    protected:
        virtual void OnPaint(PaintEventArgs^ e) override
        {
            __super::OnPaint(e);

            if (ProgressBarRenderer::IsSupported)
            {
                ProgressBarRenderer::DrawVerticalBar(e->Graphics, 
                    ClientRectangle);
                this->Parent->Text = "VerticalProgressBar Enabled";
            }
            else
            {
                this->Parent->Text = "VerticalProgressBar Disabled";
            }
        }

        // Initialize the rectangles used to paint the states of the
        // progress bar.
    private:
        void SetupProgressBar()
        {
            if (!ProgressBarRenderer::IsSupported)
            {
                return;
            }

            // Determine the size of the progress bar frame.
            this->Size = System::Drawing::Size(ClientRectangle.Width,
                (NumberChunks * (ProgressBarRenderer::ChunkThickness + 
                (2 * ProgressBarRenderer::ChunkSpaceThickness))) + 6);

            // Initialize the rectangles to draw each step of the
            // progress bar.
            progressBarRectangles = gcnew array<Rectangle>(NumberChunks);

            for (int i = 0; i < NumberChunks; i++)
            {
                // Use the thickness defined by the current visual style
                // to calculate the height of each rectangle. The size
                // adjustments ensure that the chunks do not paint over
                // the frame.

                int filledRectangleHeight = 
                    ((i + 1) * (ProgressBarRenderer::ChunkThickness +
                    (2 * ProgressBarRenderer::ChunkSpaceThickness)));

                progressBarRectangles[i] = Rectangle(
                    ClientRectangle.X + 3,
                    ClientRectangle.Y + ClientRectangle.Height - 3
                    - filledRectangleHeight,
                    ClientRectangle.Width - 6,
                    filledRectangleHeight);
            }
        }

        // Handle the timer tick; draw each progressively larger rectangle.
    private:
        void progressTimer_Tick(Object^ myObject, EventArgs^ e)
        {
            if (ticks < NumberChunks)
            {
                Graphics^ g = this->CreateGraphics();
                ProgressBarRenderer::DrawVerticalChunks(g,
                    progressBarRectangles[ticks]);
                ticks++;
            }
            else
            {
                progressTimer->Enabled = false;
            }
        }

        // Start the progress bar.
    public:
        void Start()
        {
            if (ProgressBarRenderer::IsSupported)
            {
                progressTimer->Start();
            }
            else
            {
                MessageBox::Show("VerticalScrollBar requires visual styles");
            }
        }
    };

    public ref class Form1 : public Form
    {
    private:
        VerticalProgressBar^ bar1;
        Button^ button1;

    public:
        Form1() : Form()
        {
            this->Size = System::Drawing::Size(500, 500);
            bar1 = gcnew VerticalProgressBar();
            bar1->NumberChunks = 30;
            button1 = gcnew Button();
            button1->Location = Point(150, 10);
            button1->Size = System::Drawing::Size(150, 30);
            button1->Text = "Start VerticalProgressBar";
            button1->Click += gcnew EventHandler(this, &Form1::button1_Click);
            Controls->AddRange(gcnew array<Control^> { button1, bar1 });
        }

        // Start the VerticalProgressBar.
    private:
        void button1_Click(Object^ sender, EventArgs^ e)
        {
            bar1->Start();
        }
    };
}


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

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

namespace ProgressBarRendererSample
{
    public class Form1 : Form
    {
        private VerticalProgressBar bar1 = new VerticalProgressBar();
        private Button button1 = new Button();

        public Form1()
            : base()
        {
            this.Size = new Size(500, 500);
            bar1.NumberChunks = 30;
            button1.Location = new Point(150, 10);
            button1.Size = new Size(150, 30);
            button1.Text = "Start VerticalProgressBar";
            button1.Click += new EventHandler(button1_Click);
            Controls.AddRange(new Control[] { button1, bar1 });
        }

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

        // Start the VerticalProgressBar.
        private void button1_Click(object sender, EventArgs e)
        {
            bar1.Start();
        }
    }

    public class VerticalProgressBar : Control
    {
        private int numberChunksValue;
        private int ticks;
        private Timer progressTimer = new Timer();
        private Rectangle[] progressBarRectangles;

        public VerticalProgressBar()
            : base()
        {
            this.Location = new Point(10, 10);
            this.Width = 50;

            // The progress bar will update every second.
            progressTimer.Interval = 1000;
            progressTimer.Tick += new EventHandler(progressTimer_Tick);

            // This property also calls SetupProgressBar to initialize 
            // the progress bar rectangles if styles are enabled.
            NumberChunks = 20;

            // Set the default height if visual styles are not enabled.
            if (!ProgressBarRenderer.IsSupported)
            {
                this.Height = 100;
            }
        }

        // Specify the number of progress bar chunks to base the height on.
        public int NumberChunks
        {
            get
            {
                return numberChunksValue;
            }

            set
            {
                if (value <= 50 && value > 0)
                {
                    numberChunksValue = value;
                }
                else
                {
                    MessageBox.Show("Number of chunks must be between " +
                        "0 and 50; defaulting to 10");
                    numberChunksValue = 10;
                }

                // Recalculate the progress bar size, if visual styles 
                // are active.
                if (ProgressBarRenderer.IsSupported)
                {
                    SetupProgressBar();
                }
            }
        }

        // Draw the progress bar in its normal state.
        protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaint(e);

            if (ProgressBarRenderer.IsSupported)
            {
                ProgressBarRenderer.DrawVerticalBar(e.Graphics,
                    ClientRectangle);
                this.Parent.Text = "VerticalProgressBar Enabled";
            }
            else
            {
                this.Parent.Text = "VerticalProgressBar Disabled";
            }
        }

        // Initialize the rectangles used to paint the states of the 
        // progress bar.
        private void SetupProgressBar()
        {
            if (!ProgressBarRenderer.IsSupported)
            {
                return;
            }

            // Determine the size of the progress bar frame.
            this.Size = new Size(ClientRectangle.Width,
                (NumberChunks) * (ProgressBarRenderer.ChunkThickness +
                (2 * ProgressBarRenderer.ChunkSpaceThickness)) + 6);

            // Initialize the rectangles to draw each step of the 
            // progress bar.
            progressBarRectangles = new Rectangle[NumberChunks];

            for (int i = 0; i < NumberChunks; i++)
            {
                // Use the thickness defined by the current visual style 
                // to calculate the height of each rectangle. The size 
                // adjustments ensure that the chunks do not paint over 
                // the frame.

                int filledRectangleHeight =
                    ((i + 1) * (ProgressBarRenderer.ChunkThickness +
                    (2 * ProgressBarRenderer.ChunkSpaceThickness)));

                progressBarRectangles[i] = new Rectangle(
                    ClientRectangle.X + 3,
                    ClientRectangle.Y + ClientRectangle.Height - 3
                    - filledRectangleHeight,
                    ClientRectangle.Width - 6,
                    filledRectangleHeight);
            }
        }

        // Handle the timer tick; draw each progressively larger rectangle.
        private void progressTimer_Tick(Object myObject, EventArgs e)
        {
            if (ticks < NumberChunks)
            {
                using (Graphics g = this.CreateGraphics())
                {
                    ProgressBarRenderer.DrawVerticalChunks(g,
                        progressBarRectangles[ticks]);
                    ticks++;
                }
            }
            else
            {
                progressTimer.Enabled = false;
            }
        }

        // Start the progress bar.
        public void Start()
        {
            if (ProgressBarRenderer.IsSupported)
            {
                progressTimer.Start();
            }
            else
            {
                MessageBox.Show("VerticalScrollBar requires visual styles");
            }
        }
    }
}

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



Public Class Form1
    Inherits Form
    Private bar1 As New VerticalProgressBar()
    Private button1 As New Button()
    
    
    Public Sub New() 
        Me.Size = New Size(500, 500)
        bar1.NumberChunks = 30
        button1.Location = New Point(150, 10)
        button1.Size = New Size(150, 30)
        button1.Text = "Start VerticalProgressBar"
        AddHandler button1.Click, AddressOf button1_Click
        Controls.AddRange(New Control() {button1, bar1})
    
    End Sub
    
    
    <STAThread()>  _
    Public Shared Sub Main() 
        ' The call to EnableVisualStyles below does not affect
        ' whether ProgressBarRenderer.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
    
    
    ' Start the VerticalProgressBar.
    Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) 
        bar1.Start()
    
    End Sub
End Class


Public Class VerticalProgressBar
    Inherits Control
    Private numberChunksValue As Integer
    Private ticks As Integer
    Private progressTimer As New Timer()
    Private progressBarRectangles() As Rectangle
    
    
    Public Sub New() 
        Me.Location = New Point(10, 10)
        Me.Width = 50
        
        ' The progress bar will update every second.
        progressTimer.Interval = 1000
        AddHandler progressTimer.Tick, AddressOf progressTimer_Tick
        
        ' This property also calls SetupProgressBar to initialize 
        ' the progress bar rectangles if styles are enabled.
        NumberChunks = 20
        
        ' Set the default height if visual styles are not enabled.
        If Not ProgressBarRenderer.IsSupported Then
            Me.Height = 100
        End If
    
    End Sub
    
    ' Specify the number of progress bar chunks to base the height on.
    
    Public Property NumberChunks() As Integer 
        Get
            Return numberChunksValue
        End Get
        
        Set
            If value <= 50 AndAlso value > 0 Then
                numberChunksValue = value
            Else
                MessageBox.Show("Number of chunks must be between " + "0 and 50; defaulting to 10")
                numberChunksValue = 10
            End If
            
            ' Recalculate the progress bar size, if visual styles 
            ' are active.
            If ProgressBarRenderer.IsSupported Then
                SetupProgressBar()
            End If
        End Set
    End Property
    
    
    ' Draw the progress bar in its normal state.
    Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs) 
        MyBase.OnPaint(e)
        
        If ProgressBarRenderer.IsSupported Then
            ProgressBarRenderer.DrawVerticalBar(e.Graphics, ClientRectangle)
            Me.Parent.Text = "VerticalProgressBar Enabled"
        Else
            Me.Parent.Text = "VerticalProgressBar Disabled"
        End If
    
    End Sub
    
    ' Initialize the rectangles used to paint the states of the 
    ' progress bar.
    Private Sub SetupProgressBar() 
        If Not ProgressBarRenderer.IsSupported Then
            Return
        End If
        
        ' Determine the size of the progress bar frame.
        Me.Size = New Size(ClientRectangle.Width, NumberChunks *(ProgressBarRenderer.ChunkThickness + 2 * ProgressBarRenderer.ChunkSpaceThickness) + 6)
        
        ' Initialize the rectangles to draw each step of the 
        ' progress bar.
        progressBarRectangles = New Rectangle(NumberChunks) {}
        
        Dim i As Integer
        For i = 0 To NumberChunks
            ' Use the thickness defined by the current visual style 
            ' to calculate the height of each rectangle. The size 
            ' adjustments ensure that the chunks do not paint over 
            ' the frame.
            Dim filledRectangleHeight As Integer = (i + 1)  _
        *(ProgressBarRenderer.ChunkThickness + 2 * ProgressBarRenderer.ChunkSpaceThickness)
            
            progressBarRectangles(i) = New Rectangle(ClientRectangle.X + 3, _
                ClientRectangle.Y + ClientRectangle.Height - 3 - filledRectangleHeight, _
                ClientRectangle.Width - 6, filledRectangleHeight)
        Next i
    
    End Sub
    
    ' Handle the timer tick; draw each progressively larger rectangle.
    Private Sub progressTimer_Tick(ByVal myObject As [Object], ByVal e As EventArgs) 
        If ticks < NumberChunks Then
            Dim g As Graphics = Me.CreateGraphics()
            Try
                ProgressBarRenderer.DrawVerticalChunks(g, progressBarRectangles(ticks))
                ticks += 1
            Finally
                g.Dispose()
            End Try
        Else
            progressTimer.Enabled = False
        End If
    
    End Sub
    
    ' Start the progress bar.
    Public Sub Start() 
        If ProgressBarRenderer.IsSupported Then
            progressTimer.Start()
        Else
            MessageBox.Show("VerticalScrollBar requires visual styles")
        End If
    
    End Sub
End Class

Opmerkingen

De ProgressBarRenderer klasse biedt een set static methoden die kunnen worden gebruikt om een voortgangsbalkbesturingselement weer te geven met de huidige visuele stijl van het besturingssysteem. Het weergeven van een besturingselement verwijst naar het tekenen van de gebruikersinterface van een besturingselement. Dit is handig als u een aangepast besturingselement tekent dat het uiterlijk van de huidige visuele stijl moet hebben. Als u een voortgangsbalk wilt tekenen, gebruikt u de DrawHorizontalBar of DrawVerticalBar methoden om de lege balk te tekenen en gebruikt u vervolgens de DrawHorizontalChunks of DrawVerticalChunks methoden om de elementen te tekenen die de balk invullen.

Als visuele stijlen zijn ingeschakeld in het besturingssysteem en visuele stijlen worden toegepast op het clientgebied van toepassingsvensters, worden met de methoden van deze klasse de voortgangsbalk getekend met de huidige visuele stijl. Anders werpen de methoden en eigenschappen van deze klasse een InvalidOperationException. Als u wilt bepalen of de leden van deze klasse kunnen worden gebruikt, kunt u de waarde van de IsSupported eigenschap controleren.

Deze klasse verpakt de functionaliteit van een System.Windows.Forms.VisualStyles.VisualStyleRenderer die is ingesteld op een van de elementen die worden weergegeven door de System.Windows.Forms.VisualStyles.VisualStyleElement.ProgressBar.Bar, System.Windows.Forms.VisualStyles.VisualStyleElement.ProgressBar.BarVertical, System.Windows.Forms.VisualStyles.VisualStyleElement.ProgressBar.Chunk en System.Windows.Forms.VisualStyles.VisualStyleElement.ProgressBar.ChunkVertical klassen. Zie Weergavebesturingselementen met visuele stijlen voor meer informatie.

Zie ook

• VisualStyleRenderer
• VisualStyleElement