Scrollbox的滚动条事件scrollbar事件的处理（Lazarus）

没办法，改源代码：

找到：Forms单元中scrollbox的父类：

TScrollingWinControl = class(TCustomControl)

改：

{ TScrollingWinControl }

//begin

TOnAfterScroll=procedure(ScrollKind: TScrollBarKind; OldPosition: Integer) of object;

//end

TScrollingWinControl = class(TCustomControl)

private

FHorzScrollBar: TControlScrollBar;

FVertScrollBar: TControlScrollBar;

FAutoScroll: Boolean;

FIsUpdating: Boolean;

FonAfterScroll:TOnAfterScroll;//*********add by aliyagoo.com

procedure SetHorzScrollBar(Value: TControlScrollBar);

procedure SetVertScrollBar(Value: TControlScrollBar);

function StoreScrollBars: Boolean;

protected

class procedure WSRegisterClass; override;

procedure AlignControls(AControl: TControl; var ARect: TRect); override;

procedure CreateWnd; override;

function GetClientScrollOffset: TPoint; override;

function GetLogicalClientRect: TRect; override;// logical size of client area

procedure DoOnResize; override;

procedure WMHScroll(var Message : TLMHScroll); message LM_HScroll;

procedure WMVScroll(var Message : TLMVScroll); message LM_VScroll;

function ComputeScrollbars: Boolean; virtual;

procedure ScrollbarHandler(ScrollKind: TScrollBarKind;

OldPosition: Integer); virtual;

procedure SetAutoScroll(Value: Boolean); virtual;

procedure Loaded; override;

property AutoScroll: Boolean read FAutoScroll write SetAutoScroll default False;

public

constructor Create(TheOwner : TComponent); override;

destructor Destroy; override;

procedure UpdateScrollbars;

function HasVisibleScrollbars: boolean; virtual;

class function GetControlClassDefaultSize: TPoint; override;

procedure ScrollBy(DeltaX, DeltaY: Integer);

property OnAfterScroll:TOnAfterScroll read FonAfterScroll write FonAfterScroll;//***********add by aliyagoo.com

published

property HorzScrollBar: TControlScrollBar

read FHorzScrollBar write SetHorzScrollBar stored StoreScrollBars;

property VertScrollBar: TControlScrollBar

read FVertScrollBar write SetVertScrollBar stored StoreScrollBars;

end;

然后在Scrollbox里公开属性【公开，不是发布】。

插入事件：ScrollingWinControl.inc 文件

procedure TScrollingWinControl.ScrollbarHandler(ScrollKind: TScrollBarKind;

OldPosition: Integer);

begin

if ScrollKind = sbVertical then

ScrollBy(0, FVertScrollBar.Position - OldPosition)

else

ScrollBy(FHorzScrollBar.Position - OldPosition, 0);

//***********add by aliyagoo

if Assigned(OnAfterScroll) then FOnAfterScroll(ScrollKind,OldPosition);

//***********end add

end;

http://blog.sina.com.cn/s/blog_56294d0a0100w4lx.html

巴特西

Scrollbox的滚动条事件scrollbar事件的处理（Lazarus）

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