【发布时间】：2015-10-21 18:51:02
【问题描述】：
我遇到了一个问题，即在我的应用程序中TListBox 中的项目选择不正确，表单中有HorzScrollBox。表单上有两个（或更多）TListBox。它们彼此远离放置，因此它们的绝对左坐标差大于当前设备屏幕宽度的宽度。错误出现在以下用户操作序列中。
- 从左边选择了一个项目
TListBox - HorzScrollBox 向右滚动，第二个
TListBox对用户可见，而左边的则不可见。 - HorzScrollBox 向左滚动。
- 从左侧
TListBox中选择了一个新项目。
我们得到以下图片： 新项目被选中，但即使我们上下滚动框，选择仍然绘制在先前选择的项目的位置上。
可以通过非常简单的方式重现该错误。
- 创建一个新的 Grid MetropolisUI 应用程序。
- 将左侧标准
TListBox替换为新的（会更快）。 - 将表单的宽度设置为大于屏幕宽度
- 将第二个新的
TListBox放置在HorzScrollBox中，这样就不会同时看到左右TListboxes，并且只有在滚动HorzScrollBox之后才能选择项目。 - 从任何来源（例如两个
TPrototypeBindSource）填充它们并将创建的LinkFieldControlToField的ListItemStyle属性设置为MetropolisUI。
完成。当您运行应用程序时，您会遇到问题。仅当您滚动HorzScrollBox 时才会出现该错误，因此当您选择第一个项目时看不到第二个ListBox。否则项目被正确选择（即使你滚动HorzScrollBox）。
这是表单的资源（除了样式的二进制文件，它需要存在才能重现错误）。
object GridViewForm: TGridViewForm
Left = 0
Top = 0
Caption = 'Grid Form'
ClientHeight = 946
ClientWidth = 2600
StyleBook = StyleBook2
FormFactor.Width = 1280
FormFactor.Height = 1024
FormFactor.Devices = [dkDesktop]
FormFamily = 'Main'
FullScreen = True
OnMouseUp = FormMouseUp
Touch.InteractiveGestures = [igPan]
OnGesture = FormGesture
DesignerMobile = False
DesignerWidth = 0
DesignerHeight = 0
DesignerDeviceName = ''
DesignerOrientation = 0
DesignerOSVersion = ''
object MainLayout: TLayout
Align = alContents
Height = 921.000000000000000000
Margins.Top = 25.000000000000000000
Width = 2600.000000000000000000
object HorzScrollBox1: THorzScrollBox
Align = alClient
Height = 921.000000000000000000
TabOrder = 0
Width = 2600.000000000000000000
object GroupLayout1: TLayout
Align = alLeft
Anchors = [akLeft, akTop]
Height = 905.000000000000000000
Margins.Left = 110.000000000000000000
Position.X = 110.000000000000000000
Width = 540.000000000000000000
object ListBox4: TListBox
Align = alClient
Height = 905.000000000000000000
StyleLookup = 'collectionlistbox'
TabOrder = 0
Width = 540.000000000000000000
DefaultItemStyles.ItemStyle = ''
DefaultItemStyles.GroupHeaderStyle = ''
DefaultItemStyles.GroupFooterStyle = ''
end
end
object GroupLayout2: TLayout
Align = alLeft
Anchors = [akLeft, akTop]
Height = 905.000000000000000000
Margins.Left = 40.000000000000000000
Position.X = 690.000000000000000000
Width = 1225.000000000000000000
end
object Layout1: TLayout
Align = alLeft
Anchors = [akLeft, akTop]
Height = 905.000000000000000000
Margins.Left = 40.000000000000000000
Margins.Right = 100.000000000000000000
Position.X = 1955.000000000000000000
Width = 660.000000000000000000
object Label1: TLabel
Align = alTop
AutoSize = True
Height = 40.000000000000000000
Margins.Left = 10.000000000000000000
Margins.Bottom = 5.000000000000000000
Position.X = 10.000000000000000000
StyleLookup = 'pagesubheaderlabel'
Text = 'Group Title: 4'
Width = 165.000000000000000000
WordWrap = False
end
object ListBox1: TListBox
Align = alClient
Height = 855.000000000000000000
StyleLookup = 'collectionlistbox'
TabOrder = 1
Width = 660.000000000000000000
DefaultItemStyles.ItemStyle = ''
DefaultItemStyles.GroupHeaderStyle = ''
DefaultItemStyles.GroupFooterStyle = ''
end
end
end
end
object StyleBook2: TStyleBook
Left = 632
Top = 544
ResourcesBin = {...}
end
object PrototypeBindSource1: TPrototypeBindSource
AutoActivate = True
AutoPost = False
FieldDefs = <
item
Name = 'ContactBitmapL1'
FieldType = ftBitmap
Generator = 'ContactBitmapsL'
ReadOnly = False
end
item
Name = 'ContactName1'
Generator = 'ContactNames'
ReadOnly = False
end
item
Name = 'IntField1'
FieldType = ftInteger
Generator = 'Integers'
ReadOnly = False
end>
ScopeMappings = <>
Left = 1288
Top = 456
end
object BindingsList1: TBindingsList
Methods = <>
OutputConverters = <>
Left = 20
Top = 5
object LinkFillControlToField1: TLinkFillControlToField
Category = 'Quick Bindings'
Control = ListBox4
Track = True
FillDataSource = PrototypeBindSource1
FillDisplayFieldName = 'ContactName1'
AutoFill = True
BufferCount = -1
AutoBufferCount = False
ListItemStyle = 'MetropolisUI'
FillExpressions = <
item
SourceMemberName = 'ContactBitmapL1'
ControlMemberName = 'Icon'
end
item
SourceMemberName = 'IntField1'
ControlMemberName = 'SubTitle'
end>
FillHeaderExpressions = <>
FillBreakGroups = <>
end
object LinkFillControlToField2: TLinkFillControlToField
Category = 'Quick Bindings'
Control = ListBox1
Track = True
FillDataSource = PrototypeBindSource2
FillDisplayFieldName = 'ContactName1'
AutoFill = True
BufferCount = -1
AutoBufferCount = False
ListItemStyle = 'MetropolisUI'
FillExpressions = <
item
SourceMemberName = 'FloatField1'
ControlMemberName = 'SubTitle'
end
item
SourceMemberName = 'ContactBitmap1'
ControlMemberName = 'Icon'
end>
FillHeaderExpressions = <>
FillBreakGroups = <>
end
end
object PrototypeBindSource2: TPrototypeBindSource
AutoActivate = True
AutoPost = False
FieldDefs = <
item
Name = 'ContactBitmap1'
FieldType = ftBitmap
Generator = 'ContactBitmaps'
ReadOnly = False
end
item
Name = 'ContactName1'
Generator = 'ContactNames'
ReadOnly = False
end
item
Name = 'FloatField1'
FieldType = ftSingle
Generator = 'Floats'
ReadOnly = False
end>
ScopeMappings = <>
Left = 1232
Top = 448
end
end
有人对如何应对有任何建议吗？
【问题讨论】：
标签： delphi listbox microsoft-metro firemonkey selecteditem