介绍 我想创建一个控件来为从列表中选择项提供不同于通常的用户体验。 背景 通过直接继承控件类，并在其中插入位图(用于显示当前项)和弹出框(用于显示可滚动的元素列表)，我创建了一个新控件。 所选项目的上面和下面是一个区域，可以直接选择上一个或下一个项目。项目选择由两个区域完成，执行动画显示变化执行: 选择项的第二种方法是从控件上的任何点开始向上或向下拖动鼠标。元素将是可转换为字符串的任何类型的对象的列表: 代码描述 我将代码分为三个部分:第一部分用于定义自定义属性和事件，第二部分用于用户交互，第三部分用于数据的表示。代码被完全注释并且(希望)容易理解。 一些笔记 隐藏,收缩,复制Code
''' <summary>Permits Private Components (Picture)</summary> Private components As System.ComponentModel.IContainer ''' <summary>PictureBox Showing the current item</summary> Private WithEvents PctCurrentItem As System.Windows.Forms.PictureBox ''' <summary>PictureBox Showing the List during the drag</summary> Private WithEvents PctItemList As System.Windows.Forms.PictureBox ''' <summary>Popup Window showing the list</summary> Private WithEvents PopUpD As ToolStripDropDown ''' <summary>ControlHost of PopUp Containing the PctItemList</summary> Private PopUpHost As ToolStripControlHost ''' <summary>Timer: If the DragDrop is open: Permit the list refresh checking ''' for the mouse position. If the DragDrop is closed, ''' it performs the Current shifting</summary> Private WithEvents Tmr As New Timer With {.Interval = 10} ''' <summary>Initializing</summary> Public Sub New() PopUpD = New ToolStripDropDown PctCurrentItem = New PictureBox PctItemList = New PictureBox PopUpHost = New ToolStripControlHost(PctItemList) Me.Controls.Add(PctCurrentItem) PopUpD.Items.Add(PopUpHost) Me_FontChanged(Nothing, Nothing) End Sub ''' <summary>Change of the font: resize the picture of current item, ''' Constraint the minimum size</summary> Private Sub Me_FontChanged(sender As Object, e As EventArgs) Handles Me.FontChanged Dim TextSize As SizeF = PctCurrentItem.CreateGraphics().MeasureString_ ("0", PctCurrentItem.Font) PctCurrentItem.Height = CInt(TextSize.Height + 2) Me.MinimumSize = New System.Drawing.Size(CInt(TextSize.Width * 1.5), _ PctCurrentItem.Height + 10) Me_Resize(Nothing, Nothing) End Sub ''' <summary>Permits the focus repainting</summary> Private Sub Me_GotFocus(sender As Object, e As EventArgs) _ Handles Me.GotFocus, Me.LostFocus Me.Invalidate() End Sub
我使控件的高度比渲染元素的字体高度至少高出50%，以便为上一个/下一个选择区域留出空间。我不知道这是不是一个错误的或有问题的模式，但它似乎是最简单的方式，迫使用户保留空间，但仍然允许创造一个伟大的喜爱。 更改控件的字体将执行内部元素的缩放和最小大小的设置，还将执行内部控件的重新定位和下一次刷新(通过Me_Resize)。 GotFocus和LostFocus事件将使该区域无效，因为焦点正在显示。 关于属性和事件 隐藏,收缩,复制Code
''' <summary>CurrentIndexChanged</summary> Public Event CurrentIndexChanged(sender As Object, e As EventArgs) ''' <summary>Width of arrows</summary> Private _ArrowWidth As Single = 1 ''' <summary>Width of arrows</summary> <System.ComponentModel.Browsable(True)> <System.ComponentModel.DefaultValue(1.0!)> Public Property ArrowWidth As Single Get Return _ArrowWidth End Get Set(value As Single) If _ArrowWidth <> value Then _ArrowWidth = value Me.Invalidate() End If End Set End Property ''' <summary>Color of arrows</summary> Private _ArrowColor As Color = Color.DarkGray ''' <summary>Color of arrows</summary> <System.ComponentModel.Browsable(True)> <System.ComponentModel.DefaultValue(GetType(Color), "DarkGray")> Public Property ArrowColor As Color Get Return _ArrowColor End Get Set(value As Color) If _ArrowColor <> value Then _ArrowColor = value Me.Invalidate() End If End Set End Property ''' <summary>Item List</summary> Private Property _Items As Array = New Object() {} ''' <summary>Item List</summary> ''' <remarks>DefaultValueAttribute is not settable ''' (An empty Array is always different from another empty array)</remarks> <System.ComponentModel.Browsable(True)> Public Property Items As Array Get Return _Items End Get Set(value As Array) If value.GetUpperBound(0) <> _Items.GetUpperBound(0) _ OrElse (value.GetUpperBound(0) >= 0 AndAlso Enumerable.Range(0, _ _Items.GetUpperBound(0)).Any(Function(x As Integer) value.GetValue(x) _ IsNot _Items.GetValue(x))) Then _Items = value If _CurrentIndex > _Items.GetUpperBound(0) _ Then _CurrentIndex = _Items.GetUpperBound(0) PctCurrentItem.Invalidate() End If End Set End Property ''' <summary>Index of Current Item</summary> Private _CurrentIndex As Integer = 0 ''' <summary>Index of Current Item</summary> <System.ComponentModel.Browsable(True)> <System.ComponentModel.DefaultValue(0)> Public Property CurrentIndex As Integer Get Return _CurrentIndex End Get Set(value As Integer) If value < 0 Then value = 0 If value > _Items.GetUpperBound(0) Then value = _Items.GetUpperBound(0) If value <> _CurrentIndex Then _CurrentIndex = value PctCurrentItem.Invalidate() RaiseEvent CurrentIndexChanged(Me, New EventArgs) End If End Set End Property ''' <summary>Text of Current Item</summary> Public ReadOnly Property CurrentItem As Object Get If _CurrentIndex >= 0 AndAlso _CurrentIndex <= Items.GetUpperBound(0) _ Then Return Items.GetValue(_CurrentIndex) Else Return Nothing End Get End Property
我尝试让属性添加了Browsable属性和一个默认值，以允许通过属性面板进行编辑。我不能把一个默认值的项目属性。我第一次将项目作为字符串数组放入，但我意识到，如果项目可以是任何类型对象(例如statepattern)的数组，并显示字符串表示，那么它可能更有用。这使得默认值不存在，并且属性面板中的元素更难(或不可能)可编辑性，但我认为这样更好。如果项目属性是不可浏览的，可能会更好。 CurrentIndex的变化引发了currentindexchangeevent。我做了所有引用当前指数代码通过_CurrentIndex字段,但是当它将,我使用属性使代码快(我工作的方法:如果是如此棘手,我使用内部代码的得到我想要的是管理,我使用了字段时)和智能(当我想要,我想要提出的事件)。 对用户交互 隐藏,收缩,复制Code
''' <summary>Store the Y coordinate of Mouse Down ''' (to recognize if it's a drag or a click)</summary> Private LastMouseDownY As Integer ''' <summary>The control is performing a drag selection</summary> Private IsDragging As Boolean ''' <summary>Store the Y coordinate of Start of the Drag Action ''' (it different from LastMouseDownY: there is a threshold)</summary> Private StartDragYLocation As Integer ''' <summary>Multiplier minimum of the Drag Action: ''' it's value is for the 25% of the screen height, its maximum value is 3, ''' it's minimum value is 1</summary> Private MinDragMultiplier As Single ''' <summary>Multiplier maximum of the Drag Action: ''' its value makes the drag of the all screen height is ''' over the all list scrolling</summary> Private MaxDragMultiplier As Single ''' <summary>Shift amount of the Drag</summary> Private CurrentDragYAmount As Integer ''' <summary>Current Picture Top: I don't know if the action is ''' started from the picture, from the entire control. ''' I store the location of the control into the screen</summary> Private PictureContentCurrentTop As Integer ''' <summary>List Picture Top: I don't know if the action is started from the picture, ''' from the entire control. I store the location of the control into the screen ''' </summary> Private PictureListCurrentTop As Integer ''' <summary>Number of elements into the drag panel</summary> Private MaxItemCountHeightInPanel As Integer = 7 ''' <summary>Mouse down: Store the current Y</summary> Private Sub PctCurrentItem_MouseDown(sender As Object, e As MouseEventArgs) _ Handles Me.MouseDown, PctCurrentItem.MouseDown If Not IsDragging AndAlso e.Button = Windows.Forms.MouseButtons.Left Then Me_Resize(Nothing, Nothing) LastMouseDownY = Me.PointToClient(Control.MousePosition).Y End If 'in any case: switch off the popup IsDragging = False If PopUpD.Visible Then PopUpD.Close() End Sub ''' <summary>MouseUp: If I'm not dragging, select the previous or next element</summary> Private Sub PctCurrentItem_MouseUp(sender As Object, e As MouseEventArgs) _ Handles Me.MouseUp, PctCurrentItem.MouseUp If Not IsDragging AndAlso e.Button = _ Windows.Forms.MouseButtons.Left AndAlso _Items.GetUpperBound(0) >= 0 Then If LastMouseDownY <= PctCurrentItem.Top + PctCurrentItem.Height * 0.2F Then CurrentIndex = If(_CurrentIndex = 0, Items.GetUpperBound(0), _CurrentIndex - 1) AnimationDirectionIsUp = True ElseIf LastMouseDownY >= PctCurrentItem.Top + PctCurrentItem.Height * 0.8F Then CurrentIndex = If(_CurrentIndex = Items.GetUpperBound(0), 0, _CurrentIndex + 1) AnimationDirectionIsUp = False Else Exit Sub End If ' Start the animation AnimationStartTime = Now Tmr_Tick(Nothing, Nothing) End If End Sub ''' <summary>If I'm out of the threshold, performs dragging start ''' (show the popup)</summary> Private Sub PctCurrentItem_MouseMove(sender As Object, e As MouseEventArgs) _ Handles Me.MouseMove, PctCurrentItem.MouseMove If e.Button = Windows.Forms.MouseButtons.Left _ AndAlso Not IsDragging _ AndAlso (Me.PointToClient(Control.MousePosition).Y - LastMouseDownY > 5 _ OrElse Me.PointToClient(Control.MousePosition).Y - LastMouseDownY < -5) _ AndAlso _Items.GetUpperBound(0) >= 0 Then ' Drag start: Shows the panel, with a maximum height as the 80% of the ' screen height, with 7 elements (if the item has seven elements) IsDragging = True Dim PanelHeight As Integer = PctCurrentItem.Height * _ If(Items.GetUpperBound(0) < MaxItemCountHeightInPanel, _ Items.GetUpperBound(0) + 1, MaxItemCountHeightInPanel) If PanelHeight > My.Computer.Screen.WorkingArea.Height * 0.8F _ Then PanelHeight = CInt(My.Computer.Screen.WorkingArea.Height * 0.8F) PictureListCurrentTop = CInt(Me.PointToScreen(New Point(0, 0)).Y + _ Me.Height / 2.0F - PanelHeight / 2.0F) PictureContentCurrentTop = PctCurrentItem.PointToScreen(New Point(0, 0)).Y If PictureListCurrentTop < 0 Then PictureListCurrentTop = 0 If PictureListCurrentTop + PanelHeight > _ My.Computer.Screen.WorkingArea.Height - 5 _ Then PictureListCurrentTop = My.Computer.Screen.WorkingArea.Height - _ PanelHeight - 5 ' Set the multiplier if the screen is too short If My.Computer.Screen.WorkingArea.Height * 0.8! > PctCurrentItem.Height * _ (Items.GetUpperBound(0) + 1) Then MinDragMultiplier = 1 Else MinDragMultiplier = (PctCurrentItem.Height * _ (Items.GetUpperBound(0) + 1)) / 0.8! / My.Computer.Screen.WorkingArea.Height End If If MinDragMultiplier > 3 Then MaxDragMultiplier = ((Items.GetUpperBound(0) + 1) / 2.0! - _ My.Computer.Screen.WorkingArea.Height * 0.8! / 6 / _ PctCurrentItem.Height) / (My.Computer.Screen.WorkingArea.Height / _ 4.0! / PctCurrentItem.Height) MinDragMultiplier = 3 Else MaxDragMultiplier = MinDragMultiplier End If ' set the popup StartDragYLocation = Control.MousePosition.Y CurrentDragYAmount = 0 Dim Sz As New Size(Me.Width, CInt(PanelHeight) + 2) PopUpD.MinimumSize = Sz PopUpD.MaximumSize = Sz PopUpD.Size = Sz PopUpHost.Size = Sz PctItemList.Size = New Size(Sz.Width - 2, Sz.Height - 2) ' Show the popup PopUpD.Show(Me.PointToScreen(New Point(0, 0)).X - 1, CInt(PictureListCurrentTop)) Tmr.Start() End If End Sub ''' <summary>Set the location after the show ''' (elsewhere, the PctItemList is a pixel downer)</summary> Private Sub PopUpD_Opened(sender As Object, e As EventArgs) Handles PopUpD.Opened PctItemList.Location = New Point(1, 1) End Sub
鼠标向下只存储鼠标单击的当前Y位置。它还重置了拖动事件。 如果没有拖动，则鼠标向上执行更改选择。如果指针指向上区域或下区域，它将被选择上一个/下一个元素。它会通过定时器制作的动画来显示。 在MouseMove中，我设置了一个阈值，看看用户是否在执行拖拽到PctCurrentItem_MouseMove: 隐藏,复制Code
Me.PointToClient(Control.MousePosition).Y - LastMouseDownY > 5 _ OrElse Me.PointToClient(Control.MousePosition).Y - LastMouseDownY < -5
如果通过了阈值，它将计算项目列表面板的位置和高度、拖动倍率(见下面)以及弹出面板的大小。然后它显示弹出面板，并让计时器开始执行操作。当弹出窗口显示时，带有项目列表的图片被放置在其中。 我使用了一个倍增器，以确保拖动不会直接增加鼠标移动量，但这是直接成比例的。如果元素的总高度小于屏幕高度的80%(在一个手势中滚动整个列表)，则拖动和滚动的量是相同的。如果元素的总高度大于屏幕高度的80%，则拖拽倍增器将把所有列表滚动到屏幕高度的80%。第二次，我意识到如果元素真的很多，直接乘法器不是很容易使用。所以我创建了一个MinDragMultiplier和一个MaxDragMultiplier，它们分别是: 如果整个列表的大小高度的3倍少80%屏幕高度,他们有价值,在其他地方,MinDragMultiplier值为3,另一个执行整个滚动列表的值为40%的屏幕高度,让DragMultiplier像图: 隐藏,复制Code
''' <summary>Permits to use Up and Down keys to select the previous/next element</summary> ''' <paramname="KeyData">Up and Down keys</param> ''' <returns>True</returns> Protected Overrides Function IsInputKey(KeyData As Keys) As Boolean Return KeyData = Keys.Escape OrElse KeyData = Keys.Up OrElse KeyData = Keys.Down End Function ''' <summary>Esc: Disable the dragging popup - Up/Down arrows: ''' Select the Previous/Next element</summary> Private Sub Me_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown If IsDragging AndAlso e.KeyCode = Keys.Escape Then PopUpD.Close() IsDragging = False Tmr.Stop() e.Handled = True ElseIf Not IsDragging AndAlso e.KeyCode = Keys.Up Then LastMouseDownY = 0 PctCurrentItem_MouseUp(Me, New MouseEventArgs_ (Windows.Forms.MouseButtons.Left, 1, 0, 0, 0)) e.Handled = True ElseIf Not IsDragging AndAlso e.KeyCode = Keys.Down Then LastMouseDownY = Me.Height PctCurrentItem_MouseUp(Me, New MouseEventArgs_ (Windows.Forms.MouseButtons.Left, 1, 0, Me.Height, 0)) e.Handled = True End If End Sub
我还可以用向上和向下键箭头来选择上一个/下一个元素(它们被设置为输入键，在其他地方窗口窗体执行焦点以转到上一个/下一个控件) 此外，Esc键执行关闭弹出窗口，而不执行鼠标选择在绘图期间。当鼠标左键仍在按下时，它将被检查。 关于渲染区域 隐藏,收缩,复制Code
''' <summary>DateTime of the start of the animation</summary> Private AnimationStartTime As Date ''' <summary>Animation Direction (True: Up - False: Down)</summary> Private AnimationDirectionIsUp As Boolean ''' <summary>Actual Step of the animation (0-1)</summary> Private AnimationStep As Single ''' <summary>Timer: If the DragDrop is open: ''' Performs the list refresh checking for the mouse position. ''' If the DragDrop is closed, it performs the Current shifting</summary> Private Sub Tmr_Tick(sender As Object, e As EventArgs) Handles Tmr.Tick If IsDragging Then If Control.MouseButtons = Windows.Forms.MouseButtons.Left Then ' It's still dragging Dim DragMultiplier As Single = MaxDragMultiplier If DragMultiplier > MinDragMultiplier Then If (StartDragYLocation - Control.MousePosition.Y) / _ My.Computer.Screen.WorkingArea.Height < 0.25 _ AndAlso (Control.MousePosition.Y - StartDragYLocation) / _ My.Computer.Screen.WorkingArea.Height < 0.25 Then DragMultiplier = MinDragMultiplier ElseIf (StartDragYLocation - Control.MousePosition.Y) / _ My.Computer.Screen.WorkingArea.Height > 0.5 _ OrElse (Control.MousePosition.Y - StartDragYLocation) / _ My.Computer.Screen.WorkingArea.Height > 0.5 Then DragMultiplier = MaxDragMultiplier Else DragMultiplier = MinDragMultiplier + _ (MaxDragMultiplier - MinDragMultiplier) * _ (CSng(Math.Abs(StartDragYLocation - Control.MousePosition.Y)) / _ My.Computer.Screen.WorkingArea.Height - 0.25!) * 4 End If End If Dim TmpCurrenty As Integer = _ CInt((StartDragYLocation - Control.MousePosition.Y) * DragMultiplier) If CurrentDragYAmount <> TmpCurrenty _ Then CurrentDragYAmount = TmpCurrenty : PctItemList.Invalidate() Else ' Stop to drag. Calculates the new Current Index and close the popup Dim NewItem As Double = _CurrentIndex + _ CurrentDragYAmount / PctCurrentItem.Height While NewItem < -0.5 : NewItem += _Items.GetUpperBound(0) + 1 : End While While NewItem > _Items.GetUpperBound(0) + 0.5 : _ NewItem -= _Items.GetUpperBound(0) + 1 : End While CurrentIndex = CInt(NewItem) PopUpD.Close() IsDragging = False Tmr.Stop() End If Else ' It's animating Dim TmpAnimationStep As Single = CSng((Now - AnimationStartTime).TotalSeconds * 4) If TmpAnimationStep >= 1 Then ' End of animation AnimationStep = 0 PctCurrentItem.Invalidate() Tmr.Stop() Else AnimationStep = (1 - TmpAnimationStep) * If(AnimationDirectionIsUp, -1, 1) Tmr.Start() End If PctCurrentItem.Invalidate() End If End Sub
咯定时器有两个不同的功能:如果用户选择前一个/下一个元素(通过点击进入上/下区域或通过按上下键箭头,IsDragging字段是假的),它执行一个动画显示选择改变(设置一个AnimationStep和失效的图片,然后油漆事件执行动画)或控件交互列表:如果鼠标左键仍压,计算实际的列表位置通过DragMultiplier如上所示,CurrentDragYAmount是当前项之间的距离位置PctCurrentItem和当前项位置显示PctItemList,如果鼠标不是仍然按下,执行新项目选择。 隐藏,收缩,复制Code
''' <summary>If there is an animation: paint the current element and the previous ''' (if the animation is to the next) or the next (if the animation is to the previous) ''' </summary> Private Sub PnlCurrentItem_Paint(sender As Object, e As PaintEventArgs) _ Handles PctCurrentItem.Paint If _CurrentIndex >= 0 AndAlso _CurrentIndex <= Items.GetUpperBound(0) Then Dim Str As String = Items.GetValue(_CurrentIndex).ToString(), _ SizeStr As SizeF = e.Graphics.MeasureString(Str, PctCurrentItem.Font) If AnimationStep = 0 Then ' No animations: draw the current element e.Graphics.DrawString(Str, PctCurrentItem.Font, _ New SolidBrush(Me.ForeColor), _ CInt(PctCurrentItem.Width / 2 - SizeStr.Width / 2), 1) Else ' Animations: Draw two elements e.Graphics.DrawString(Str, PctCurrentItem.Font, _ New SolidBrush(Me.ForeColor), _ CInt(PctCurrentItem.Width / 2 - SizeStr.Width / 2), _ 1 + AnimationStep * SizeStr.Height) Dim Indx As Integer = _CurrentIndex + If(AnimationDirectionIsUp, 1, -1) If Indx < 0 Then Indx = Items.GetUpperBound(0) ElseIf Indx > Items.GetUpperBound(0) Then Indx = 0 End If Str = Items.GetValue(Indx).ToString() SizeStr = e.Graphics.MeasureString(Str, PctCurrentItem.Font) e.Graphics.DrawString(Str, PctCurrentItem.Font, _ New SolidBrush(Me.ForeColor), _ CInt(PctCurrentItem.Width / 2 - SizeStr.Width / 2), _ 1 + AnimationStep * SizeStr.Height + PctCurrentItem.Height * _ If(AnimationDirectionIsUp, 1, -1)) End If End If If Not Me.Enabled Then e.Graphics.FillRectangle(New SolidBrush_ (Color.FromArgb(128, 255, 255, 255)), 0, 0, PctCurrentItem.Width, _ PctCurrentItem.Height) End Sub
CurrentItem的绘制执行动画帧(如果动画正在运行)，或者显示当前项。如果控件被禁用，最后一行将执行衰落。 隐藏,收缩,复制Code
''' <summary>Draw the list of all items. It's made two times ''' (if the list is to draw from one of latest) according to the animation</summary> Private Sub PctItemList_Paint(sender As Object, e As PaintEventArgs) _ Handles PctItemList.Paint If IsDragging Then Dim CurrentY As Integer = PictureContentCurrentTop - _ PictureListCurrentTop - _CurrentIndex * PctCurrentItem.Height - _ CurrentDragYAmount, Str As String, SizeStr As SizeF While CurrentY > 0 : CurrentY -= PctCurrentItem.Height * _ (_Items.GetUpperBound(0) + 1) : End While While CurrentY < -PctCurrentItem.Height * _ (_Items.GetUpperBound(0) + 1) : CurrentY += PctCurrentItem.Height * _ (_Items.GetUpperBound(0) + 1) : End While For I As Integer = 0 To 1 For J As Integer = 0 To Items.GetUpperBound(0) If CurrentY > -PctCurrentItem.Height AndAlso CurrentY < _ PctItemList.Height Then Str = Items.GetValue(J).ToString() SizeStr = e.Graphics.MeasureString(Str, Me.Font) e.Graphics.DrawString(Str, Me.Font, _ New SolidBrush(Me.ForeColor), _ CInt(Me.Width / 2 - SizeStr.Width / 2), CurrentY) End If CurrentY += PctCurrentItem.Height Next J Next I e.Graphics.DrawRectangle(New Pen(Color.FromArgb(64, 0, 0, 0)), 0, _ PictureContentCurrentTop - PictureListCurrentTop, _ PctItemList.Width - 1, PctCurrentItem.Height) End If End Sub
在拖动过程中，计时器会使ItemList失效，看起来像是滚动的动画。实际上，只绘制那些在可见区域可见的元素。 如果它计算上面的项来显示和当前位置会更有效率，但是今天我很懒。: -) 最后:箭画: 隐藏,复制Code
''' <summary>Draw arrow buttons</summary> Private Sub Me_Paint(sender As Object, e As PaintEventArgs) Handles Me.Paint Dim SizeArrow As Single = PctCurrentItem.Top - 1 Dim ArrowWidth As Single = SizeArrow / 4 e.Graphics.DrawLines(New Pen(ArrowColor, ArrowWidth * _ArrowWidth), _ {New PointF(Me.Width / 2.0F - SizeArrow * 2, SizeArrow), _ New PointF(Me.Width / 2.0F, 0), New PointF(Me.Width / 2.0F + _ SizeArrow * 2, SizeArrow)}) e.Graphics.DrawLines(New Pen(ArrowColor, ArrowWidth * _ArrowWidth), _ {New PointF(Me.Width / 2.0F - SizeArrow * 2, Me.Height - SizeArrow), _ New PointF(Me.Width / 2.0F, Me.Height - 0), New PointF(Me.Width / 2.0F + _ SizeArrow * 2, Me.Height - SizeArrow)}) If Me.Focused Then e.Graphics.DrawRectangle(New Pen(SystemColors.Highlight) _ With {.DashStyle = Drawing2D.DashStyle.Dash}, 0, 0, Me.Width - 1, Me.Height - 1) If Not Me.Enabled Then e.Graphics.FillRectangle(New SolidBrush_ (Color.FromArgb(128, 255, 255, 255)), 0, 0, Me.Width, Me.Height) End Sub
和控制定位时，会有一个大小调整: 隐藏,复制Code
''' <summary>Resize the picture of the current item</summary> Private Sub Me_Resize(sender As Object, e As EventArgs) Handles Me.Resize PctCurrentItem.Left = 1 PctCurrentItem.Width = Me.Width - 2 PctCurrentItem.Top = (Me.Height - PctCurrentItem.Height) \ 2 Me.Invalidate() End Sub
使用控制 ItemList可以通过一个简单的赋值设置。设置闹钟的时间，你可以做两种序列: 隐藏,复制Code
DlcHour.Items = New String() {"00 am", "01 am", "02 am", [...] "11 am", "12 pm", "01 pm", .. }
或者: 隐藏,复制Code
DlcHour.Items = Enumerable.Range(0, 24).Select(Function(x As Integer) x.ToString("00")).ToArray()
设置StatePattern数组: 隐藏,复制Code
DlcSetUp.Items = New Object () {StatePattern1, StatePattern2, StatePattern3}
要拦截用户选择，可以使用currentindexchangeevent。 在附加的示例中，我指出了使用该控件的一些不同方法。我用它从字符串数组中选择一个元素: 隐藏,复制Code
DLCString.Items = {"First Element", "Second Element", "Third Element", "Fourth Element"}
一个整数数组: 隐藏,复制Code
DLCAThousand.Items = Enumerable.Range(0, 1000).ToArray()
格式化数字数组: 隐藏,复制Code
DLCMinutes.Items = Enumerable.Range(0, 60).Select(Function(x) x.ToString("00")).ToArray()
枚举值数组: 隐藏,复制Code
DLCObjects1.Items = [Enum].GetValues(GetType(FormBorderStyle))
和一个对象数组: 隐藏,复制Code
Private Class AClass Public Property Descr As String Public Property Value As Color Public Overrides Function ToString() As String Return Descr End Function End Class Dim MyArray As AClass() = {New AClass With {.Descr = "Red", .Value = Color.Red}, New AClass With {.Descr = "Green", .Value = Color.Green}, New AClass With {.Descr = "Blue", .Value = Color.Blue}, New AClass With {.Descr = "Yellow", .Value = Color.Yellow}} [...] DLCObjects2.Items = MyArray
有数千个元素的控制，你可以看到加速度斜坡的效果。如果您想选择一个near元素，选择起来很容易。如果你想选择一个远的元素，你必须在这个近的范围内。 选择的效果会显示在事件拦截器中: 隐藏,复制Code
Private Sub DLCString_CurrentIndexChanged(sender As Object, e As EventArgs) _ Handles DLCString.CurrentIndexChanged Me.Text = DLCString.CurrentItem.ToString() End Sub Private Sub DLCObjects1_CurrentIndexChanged(sender As Object, e As EventArgs) _ Handles DLCObjects1.CurrentIndexChanged Me.FormBorderStyle = CType(DLCObjects1.CurrentItem, FormBorderStyle) End Sub Private Sub DLCObjects2_CurrentIndexChanged(sender As Object, e As EventArgs) _ Handles DLCObjects2.CurrentIndexChanged Me.BackColor = CType(DLCObjects2.CurrentItem, AClass).Value End Sub
的兴趣点 可能需要将列表上方和下方的元素创建为真正的按钮。他们的表现就不那么可爱了。我并没有过多地关注它们。 我想在WPF中创建这个控件，但我没有做到。我想看看能够做到的人是如何做到的。 我想在一个DateTimePicker控件替换年和月像这样的控件: → 我不知道这是否可能(我认为如果我想把年度控制分成两个不同的部分，一年和一天，那就不简单了)。 本文转载于：http://www.diyabc.com/frontweb/news360.html