Question

我需要一种避免在面板上闪烁的方法，我在这里提出了很多类似的问题，并且在世界各地试图向专家询问，我尝试过很多技巧，扩展面板，创建框架，控制方式，浪费了很多时间，浪费时间学习那些不起作用的东西......我在这一点上陷入困境。

...没有什么能像预期的那样真正起作用，我找到的最好的“闪烁减速器”是“Createparams”覆盖子，但是这种方法使任何Form / App的任何操作速度都慢了x20倍，I如果这意味着应用程序性能下降，则不要松散闪烁（至少如果与CreateParams的性能相同，则不会这样。）

在这个视频中你可以看到我的测试表格有一个50％透明的面板，其中里面有图片框，背景图像设置为“缩放”分层，当我向上或向下滚动时，我得到了很多闪烁。

http://www.youtube.com/watch?v=zIBDTMjrDd4&feature=youtu.be

我使用“CreateParams”方法，如果我不使用“CreateParams”，你真的不会看到我的面板闪烁会发生什么，真的很可怕。

这是没有闪烁时的面板：

enter image description here

这是小组片刻，它闪烁着：

enter image description here

这是完整的课程：

It is a Windows Form proyect
VS2012
Framework 3.5
On Windows 7 x64
Application Visual Styles is ON
Double Buffer is ON
Panel and pictureboxes are default controls

（我认为没必要说我已经尝试了所有可能的视觉和环境配置，人们说我永远忘记了闪烁。）

Public Class Form1

    Dim Scroll_Position As Int32 = 0
    Dim Button_Down_Is_Pressed As Boolean = False
    Dim Button_Up_Is_Pressed As Boolean = False
    Dim WithEvents Progressive_Scroll_Timer As New Timer
    Dim SmallChange As Int32 = 5
    Dim Largechange As Int32 = 10

    ' Sub which reduces the Flickering, but this sub makes x20 times slower any operation of any Form/Application.
    Protected Overrides ReadOnly Property CreateParams() As CreateParams
        Get
            Dim cp As CreateParams = MyBase.CreateParams
            cp.ExStyle = cp.ExStyle Or &H2000000
            Return cp
        End Get
    End Property 'CreateParams

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        ' Me.BackColor = Color.FromArgb(255, 0, 0, 0)
        ' Me.TransparencyKey = Color.FromArgb(255, 0, 0, 0)
        Panel1.VerticalScroll.Maximum = 999999999
        Progressive_Scroll_Timer.Interval = 50
        Panel1.BackColor = Color.FromArgb(150, 0, 0, 0)
    End Sub

    Private Sub Panel_MouseHover(sender As Object, e As EventArgs) Handles Panel1.MouseHover
        sender.focus()
    End Sub

    Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Progressive_Scroll_Timer.Tick
        If Button_Down_Is_Pressed Then
            Scroll_Down(SmallChange)
        ElseIf Button_Up_Is_Pressed Then
            Scroll_Up(SmallChange)
        Else
            sender.stop()
        End If
    End Sub

    Private Sub Scroll_Up(ByVal Change As Int32)
        Scroll_Position -= Change
        Panel1.SuspendLayout()
        Try : Panel1.VerticalScroll.Value = Scroll_Position : Catch : Scroll_Position += Change : End Try
        Panel1.ResumeLayout()
    End Sub

    Private Sub Scroll_Down(ByVal Change As Int32)
        Scroll_Position += Change
        Try : Panel1.VerticalScroll.Value = Scroll_Position : Catch : Scroll_Position -= Change : End Try
    End Sub

    Private Sub Button_Down_MouseDown(sender As Object, e As MouseEventArgs) Handles Button2.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left Then
            Button_Down_Is_Pressed = True
            Progressive_Scroll_Timer.Start()
        End If
    End Sub

    Private Sub Button_Up_MouseDown(sender As Object, e As MouseEventArgs) Handles Button1.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left Then
            Button_Up_Is_Pressed = True
            Progressive_Scroll_Timer.Start()
        End If
    End Sub

    Private Sub Button_Down_MouseUp(sender As Object, e As MouseEventArgs) Handles Button2.MouseUp
        Button_Down_Is_Pressed = False
    End Sub

    Private Sub Button_Up_MouseUp(sender As Object, e As MouseEventArgs) Handles Button1.MouseUp
        Button_Up_Is_Pressed = False
    End Sub

    Private Sub Form_MouseWheel(ByVal sender As Object, ByVal e As MouseEventArgs) Handles Panel1.MouseWheel
        If Panel1.Focused Then
            Select Case Math.Sign(e.Delta)
                Case Is > 0 : Scroll_Up(Largechange)
                Case Is < 0 : Scroll_Down(Largechange)
            End Select
        End If
    End Sub

End Class

Answer 1

将Panel＆＃39; AutoScroll属性设置为true。如果没有这个，滚动似乎不起作用。添加从DoubleBufferedPanel类继承的Panel类，并将.DoubleBuffered属性设置为true：

Public Class DoubleBufferedPanel
    Inherits Panel

    Public Sub New()
        DoubleBuffered = True
    End Sub
End Class

现在转到隐藏的InitializeComponent子（右键单击Panel1变量，然后点击Go To Definition）。在需要的地方（两个地方）将Panel类型替换为DoubleBufferedPanel：

Me.Panel1 = New WindowsApplication4.DoubleBufferedPanel()
....
Friend WithEvents Panel1 As WindowsApplication4.DoubleBufferedPanel

闪烁应该停止（尽管还有一些其他效果）。删除CreateParams以提高速度。

P.S。总的来说，这不是一个好主意（移动复杂的半透明图像）。为什么不使用像ListView这样的东西？为什么不在不使用Panel的情况下自行移动图像？如果您想获得最佳速度，只需使用.BackgroundImage和Bitmap类在表单（Graphics）上绘制图片。

P.P.S。使用Panel以编程方式滚动.AutoScroll = true似乎存在一些严重错误。我不得不重新分配滚动值以防止严重的抖动。我已将案件隔离，并将向Microsoft提交错误报告。

Answer 2

使用代表class及其内容的复杂panel，然后绘制（GDI+）到Picturebox上的内容可以很好地渲染。我做过几个这样的项目。

Answer 3

您可以将表单的DoubleBuffered属性设置为True

修改：

我认为你不需要Timer。所以，你修改过的代码有点像这样：

Public Class Form1

    Dim Scroll_Position As Int32 = 0
    Dim SmallChange As Int32 = 5
    Dim Largechange As Int32 = 10

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        ' Me.BackColor = Color.FromArgb(255, 0, 0, 0)
        ' Me.TransparencyKey = Color.FromArgb(255, 0, 0, 0)
        Panel1.VerticalScroll.Maximum = 999999999
        Panel1.BackColor = Color.FromArgb(150, 0, 0, 0)
    End Sub

    Private Sub Panel_MouseHover(sender As Object, e As EventArgs) Handles Panel1.MouseHover
        sender.focus()
    End Sub

    Private Sub Scroll_Up(ByVal Change As Int32)
        Try
            Scroll_Position -= Change
            Panel1.VerticalScroll.Value = Scroll_Position 
        End Try
    End Sub

    Private Sub Scroll_Down(ByVal Change As Int32)
        Try
            Scroll_Position += Change
            Panel1.VerticalScroll.Value = Scroll_Position 
        End Try
    End Sub

    Private Sub Button_Down_MouseDown(sender As Object, e As MouseEventArgs) Handles Button2.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left Then
            scrollDown(smallChange)
        End If
    End Sub

    Private Sub Button_Up_MouseDown(sender As Object, e As MouseEventArgs) Handles Button1.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left Then
            scrollUp(SmallChange)
        End If
    End Sub

    Private Sub Form_MouseWheel(ByVal sender As Object, ByVal e As MouseEventArgs) Handles Panel1.MouseWheel
        If Panel1.Focused Then
            Select Case Math.Sign(e.Delta)
                Case Is > 0 : Scroll_Up(Largechange)
                Case Is < 0 : Scroll_Down(Largechange)
            End Select
        End If
    End Sub

End Class

这可能不是解决方案，但这是我方的努力。

Answer 4

将其放入表单加载

' to remove flick
Dim aProp As PropertyInfo = GetType(Panel).GetProperty("DoubleBuffered", BindingFlags.NonPublic Or BindingFlags.Instance)
        aProp.SetValue(Panel7, True, Nothing)

将Panel7替换为带有背景图像的控件名称。

面板与Pictureboxes闪烁

4 个答案: