下面是TDragClass的源代码,比如多，可以拷去机上试试，再慢慢看：
//------TDragClass------------------------
unit uDrag;
interface
uses Windows, Messages,Classes,SysUtils,Controls,Graphics,
uDragPoint,StdCtrls;
type
//控件的八个点，用于拉动大小
TPointRec=record
LeftTop:TDragPoint;
LeftBottom:TDragPoint;
RightTop:TDragPoint;
RightButton:TDragPoint;
LeftMid:TDragPoint;
TopMid:TDragPoint;
RightMid:TDragPoint;
ButtonMid:TDragPoint;
end;
TDragClass=class
private
FConList:TList; //保存控件的列表
FCurActiveCon:Integer; //当前活动控件
FPointRec:TPointRec; //当前控件的边缘的八个小点
//跳跃式移动的成员
FisMoveStep:Boolean;
FMoveStep:integer;
MoveX,MoveY:integer;
//控件事件相关的成员
FConMouseDown:TMouseEvent;
FConMouseMove:TMouseMoveEvent;
FConMouseup:TMouseEvent;
isDown:Boolean;
prevP,nextP:TPoint;
protected
//-------对移动点的操作--
procedure CreateDragPoint(PointParent:TWinControl);
procedure SetPointPos(posRect:TRect);
procedure SetPointParent(PointParent:TWinControl);
procedure SetPointEvent;
procedure SetCurActiveCon(curCon:Pointer);
//----------------------
procedure MoveLeftTopPoint;
procedure AlignLeftTop;
procedure MoveLeftBottomPoint;
procedure AlignLeftBottom;
procedure MoveRightTopPoint;
procedure AlignRightTop;
procedure MoveRightBottomPoint;
procedure AlignRightBottom;
procedure MoveLeftMidPoint;
procedure AlignLeftMid;
procedure MoveTopMidPoint;
procedure AlignTopMid;
procedure MoveRightMidPoint;
procedure AlignRightMid;
procedure MoveBottomMidPoint;
procedure AlignBottomMid;
procedure reSizeCon;
//当前控件事件和移动点事件处理------------
procedure ConMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure ConMouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
procedure ConMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure PointMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure PointMouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
procedure PointMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure SetisMoveStep(value:Boolean);
procedure SetMoveStep(value:integer);
public
constructor create(PointParent:TWinControl);
destructor destroy; override;
function addControl(AddCon:Pointer):Boolean; //important
procedure SetPointVisible(Visibled:Boolean);
property isMoveStep:Boolean read FisMoveStep write SetisMoveStep;
property MoveStep:Integer read FMoveStep write SetMoveStep;
end;
implementation
{ TDragClass }
constructor TDragClass.create(PointParent:TWinControl);
begin
inherited Create;
FConList:=TList.Create;
FCurActiveCon:=-1;
isDown:=False;
FisMoveStep:=False;
FMoveStep:=5;
FConMouseDown:=ConMouseDown;
FConMouseMove:=ConMouseMove;
FConMouseup:=ConMouseUp;
CreateDragPoint(PointParent);
SetPointVisible(false);
SetPointEvent;
end;
destructor TDragClass.destroy;
begin
FreeAndNil(FConList);
FPointRec.LeftTop.Free;
FPointRec.LeftBottom.Free;
FPointRec.RightTop.Free;
FPointRec.RightButton.Free;
FPointRec.LeftMid.Free;
FPointRec.TopMid.Free;
FPointRec.RightMid.Free;
FPointRec.ButtonMid.Free;
inherited;
end;
//加一个控件进入拖拉类
function TDragClass.addControl(AddCon: Pointer): Boolean;
var TempCon:TControl; R:TRect;
i:integer;
begin
result:=True;
if TControl(AddCon).Parent=nil then
begin
result:=false;
exit;
end;
//如果该控件已经在列表中了，则加入失败
for i:=0 to FConList.Count-1 do
if Integer(AddCon)=Integer(FConList.Items[i]) then
begin
result:=false;
exit;
end;
//将控件加入列表中，并指定当前的控件的索引
FConList.Add(AddCon);
FCurActiveCon:=FConList.Count-1;
TempCon:=TControl(AddCon);
TempCon.Cursor:=crSizeAll;
TempCon.Parent.DoubleBuffered:=True; //使用双缓冲技术
//折中方案，指定控件鼠标事件
TButton(TempCon).OnMouseDown:=FconMouseDown;
TButton(TempCon).OnMouseMove:=FconMouseMove;
TButton(TempCon).OnMouseUp:=FconMouseUp;
//画控件周围的八个小点
R.Left:=TempCon.Left;
R.Top:=TempCon.Top;
R.Right:=TempCon.Left+TempCon.Width;
R.Bottom:=TempCon.Top+TempCon.Height;
SetPointParent(TempCon.Parent);
SetPointPos(R);
SetPointVisible(true);
end;
//设置八小点的可见性
procedure TDragClass.SetPointVisible(Visibled: Boolean);
begin
FPointRec.LeftTop.Visible:=Visibled;
FPointRec.LeftBottom.Visible:=Visibled;
FPointRec.RightTop.Visible:=Visibled;
FPointRec.RightButton.Visible:=Visibled;
FPointRec.LeftMid.Visible:=Visibled;
FPointRec.TopMid.Visible:=Visibled;
FPointRec.RightMid.Visible:=Visibled;
FPointRec.ButtonMid.Visible:=Visibled;
end;
//设置小点事件
procedure TDragClass.SetPointEvent;
begin
FPointRec.LeftTop.OnMouseDown:=PointMouseDown;
FPointRec.LeftTop.OnMouseMove:=PointMouseMove;
FPointRec.LeftTop.onMouseUp:=PointMouseUp;
FPointRec.LeftBottom.OnMouseDown:=PointMouseDown;
FPointRec.LeftBottom.OnMouseMove:=PointMouseMove;
FPointRec.LeftBottom.onMouseUp:=PointMouseUp;
FPointRec.RightTop.OnMouseDown:=PointMouseDown;
FPointRec.RightTop.OnMouseMove:=PointMouseMove;
FPointRec.RightTop.onMouseUp:=PointMouseUp;
FPointRec.RightButton.OnMouseDown:=PointMouseDown;
FPointRec.RightButton.OnMouseMove:=PointMouseMove;
FPointRec.RightButton.onMouseUp:=PointMouseUp;
FPointRec.LeftMid.OnMouseDown:=PointMouseDown;
FPointRec.LeftMid.OnMouseMove:=PointMouseMove;
FPointRec.LeftMid.onMouseUp:=PointMouseUp;
FPointRec.TopMid.OnMouseDown:=PointMouseDown;
FPointRec.TopMid.OnMouseMove:=PointMouseMove;
FPointRec.TopMid.onMouseUp:=PointMouseUp;
FPointRec.RightMid.OnMouseDown:=PointMouseDown;
FPointRec.RightMid.OnMouseMove:=PointMouseMove;
FPointRec.RightMid.onMouseUp:=PointMouseUp;
FPointRec.ButtonMid.OnMouseDown:=PointMouseDown;
FPointRec.ButtonMid.OnMouseMove:=PointMouseMove;
FPointRec.ButtonMid.onMouseUp:=PointMouseUp;
end;
//确定控件边缘八个小点的位置
procedure TDragClass.SetPointPos(posRect: TRect);
begin
FPointRec.LeftTop.Left:=posRect.Left-6;
FPointRec.LeftTop.Top:=posRect.Top-6;
FPointRec.LeftBottom.Left:=PosRect.Left-6;
FPointRec.LeftBottom.Top:=PosRect.Bottom;
FPointRec.RightTop.Left:=posRect.Right;
FPointRec.RightTop.Top:=posRect.Top-6;
FPointRec.RightButton.Left:=PosRect.Right;
FPointRec.RightButton.Top:=PosRect.Bottom;
FPointRec.LeftMid.Left:=posRect.Left-6;
FPointRec.LeftMid.Top:=(posRect.Top+posRect.Bottom) div 2 - 3;
FPointRec.TopMid.Left:=(posRect.Left+posRect.Right) div 2 -3;
FPointRec.TopMid.Top:=PosRect.Top-6;
FPointRec.RightMid.Left:=posRect.Right;
FPointRec.RightMid.Top:=(posRect.Top+posRect.Bottom) div 2 - 3;
FPointRec.ButtonMid.Left:=(posRect.Left+posRect.Right) div 2 -3;
FPointRec.ButtonMid.Top:=PosRect.Bottom;
end;
//创建八个小点
procedure TDragClass.CreateDragPoint(PointParent:TWinControl);
begin
FPointRec.LeftTop:=TDragPoint.Create(nil);
FPointRec.LeftTop.Cursor:=crSizeNWSE;
FPointRec.LeftBottom:=TDragPoint.Create(nil);
FPointRec.LeftBottom.Cursor:=crSizeNESW;
FPointRec.RightTop:=TDragPoint.Create(nil);
FPointRec.RightTop.Cursor:=crSizeNESW;
FPointRec.RightButton:=TDragPoint.Create(nil);
FPointRec.RightButton.Cursor:=crSizeNWSE;
FPointRec.LeftMid:=TDragPoint.Create(nil);
FPointRec.LeftMid.Cursor:=crSizeWE;
FPointRec.TopMid:=TDragPoint.Create(nil);
FPointRec.TopMid.Cursor:=crSizeNS;
FPointRec.RightMid:=TDragPoint.Create(nil);
FPointRec.RightMid.Cursor:=crSizeWE;
FPointRec.ButtonMid:=TDragPoint.Create(nil);
FPointRec.ButtonMid.Cursor:=crSizeNS;
SetPointParent(PointParent);
end;
//------当前控件事件处理-------------------------
//处理点下的事件
procedure TDragClass.ConMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
var TempCon:TControl; R:TRect;
begin
if Button=mbLeft then
begin
isDown:=True;
GetCursorPos(PrevP);
end;
TempCon:=TControl(Sender);
SetPointParent(TempCon.Parent);
R.Left:=TempCon.Left;
R.Top:=TempCon.Top;
R.Right:=TempCon.Left+TempCon.Width;
R.Bottom:=TempCon.Top+TempCon.Height;
MoveX:=0; MoveY:=0;
SetPointPos(R);
SetPointvisible(true);
SetCurActiveCon(TempCon);
end;
//处理当前控件移动的消息
procedure TDragClass.ConMouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
var offsetX,offsetY:integer; con:TControl;
r:TRect;
begin
if isDown and (Shift=[ssLeft])then
begin
GetCursorPos(nextP);
offsetX:=NextP.X-PrevP.X;
offSetY:=NextP.Y-PrevP.Y;
Con:=TControl(Sender);
if not FisMoveStep then
begin
Con.Left:=Con.Left+offSetX;
Con.Top:=Con.Top+offSetY;
end
else begin
MoveX:=MoveX+offsetX;
MoveY:=MoveY+offsetY;
if Abs(MoveX)>=FMoveStep then
begin
Con.Left:=Con.Left+MoveX;
MoveX:=0;
end;
if Abs(MoveY)>FMoveStep then
begin
Con.Top:=Con.Top+MoveY;
MoveY:=0;
end;
end;
R.Left:=Con.Left;
R.Top:=Con.Top;
R.Right:=Con.Left+Con.Width;
R.Bottom:=Con.Top+Con.Height;
SetPointPos(R);
prevP:=nextP;
end;
end;
//处理当前控件鼠标弹起的消息
procedure TDragClass.ConMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
isDown:=False;
end;
//－－－－－－－－－－－－－－－－－－－－－－－－
//设置八个点的父子关系
procedure TDragClass.SetPointParent(PointParent: TWinControl);
begin
FPointRec.LeftTop.Parent:=PointParent;
FPointRec.LeftBottom.Parent:=PointParent;
FPointRec.RightTop.Parent:=PointParent;
FPointRec.RightButton.Parent:=PointParent;
FPointRec.LeftMid.Parent:=PointParent;
FPointRec.TopMid.Parent:=PointParent;
FPointRec.RightMid.Parent:=PointParent;
FPointRec.ButtonMid.Parent:=PointParent;
end;
//得到当前活动窗口
procedure TDragClass.SetCurActiveCon(curCon: Pointer);
var i:integer;
begin
for i:=0 to FConList.Count-1 do
if Integer(curCon)=Integer(FConList.Items[i]) then
begin
FCurActiveCon:=i;
break;
end;
end;
//----------------------------------
//八个小点的处理消息
procedure TDragClass.PointMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
if Button= mbLeft then
begin
moveX:=0; moveY:=0;
if Sender=FPointRec.LeftTop then
begin
FpointRec.LeftTop.isDown:=True;
GetCursorPos(FPointRec.LeftTop.PrevP);
end
else if Sender=FPointRec.RightTop then
begin
FpointRec.RightTop.isDown:=True;
GetCursorPos(FPointRec.RightTop.PrevP);
end
else if Sender=FPointRec.LeftBottom then
begin
FpointRec.LeftBottom.isDown:=True;
GetCursorPos(FPointRec.LeftBottom.PrevP);
end
else if Sender=FPointRec.RightButton then
begin
FpointRec.RightButton.isDown:=True;
GetCursorPos(FPointRec.RightButton.PrevP);
end
else if Sender=FPointRec.LeftMid then
begin
FpointRec.LeftMid.isDown:=True;
GetCursorPos(FPointRec.LeftMid.PrevP);
end
else if Sender=FPointRec.TopMid then
begin
FpointRec.TopMid.isDown:=True;
GetCursorPos(FPointRec.TopMid.PrevP);
end
else if Sender=FPointRec.RightMid then
begin
FpointRec.RightMid.isDown:=True;
GetCursorPos(FPointRec.RightMid.PrevP);
end
else if Sender=FPointRec.ButtonMid then
begin
FpointRec.ButtonMid.isDown:=True;
GetCursorPos(FPointRec.ButtonMid.PrevP);
end;
end;
end;
procedure TDragClass.PointMouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
begin
if Shift=[ssLeft] then
begin
if FPointRec.LeftTop.isDown then
begin
MoveLeftTopPoint;
reSizeCon
end
else if FPointRec.LeftBottom.isDown then
begin
MoveLeftBottomPoint;
reSizeCon
end
else if FPointRec.RightTop.isDown then
begin
MoveRightTopPoint;
reSizeCon
end
else if FPointRec.RightButton.isDown then
begin
MoveRightBottomPoint;
reSizeCon
end
else if FPointRec.LeftMid.isDown then
begin
MoveLeftMidPoint;
reSizeCon
end
else if FPointRec.TopMid.isDown then
begin
MoveTopMidPoint;
reSizeCon
end
else if FPointRec.RightMid.isDown then
begin
MoveRightMidPoint;
reSizeCon
end
else if FPointRec.ButtonMid.isDown then
begin
MoveBottomMidPoint;
reSizeCon
end
end;
end;
procedure TDragClass.PointMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
if Button= mbLeft then
begin
if (FpointRec.LeftTop.isDown) and
(Sender=FpointRec.LeftTop) then
FpointRec.LeftTop.isDown:=False
else if (FpointRec.LeftBottom.isDown) and
(Sender=FpointRec.LeftBottom) then
FpointRec.LeftBottom.isDown:=False
else if (FpointRec.RightTop.isDown) and
(Sender=FpointRec.RightTop) then
FpointRec.RightTop.isDown:=False
else if (FpointRec.RightButton.isDown) and
(Sender=FpointRec.RightButton) then
FpointRec.RightButton.isDown:=False
else if (FpointRec.LeftMid.isDown) and
(Sender=FpointRec.LeftMid) then
FpointRec.LeftMid.isDown:=False
else if (FpointRec.TopMid.isDown) and
(Sender=FpointRec.TopMid) then
FpointRec.TopMid.isDown:=False
else if (FpointRec.RightMid.isDown) and
(Sender=FpointRec.RightMid) then
FpointRec.RightMid.isDown:=False
else if (FpointRec.ButtonMid.isDown) and
(Sender=FpointRec.ButtonMid) then
FpointRec.ButtonMid.isDown:=False;
end;
end;
//左顶点的移动
procedure TDragClass.MoveLeftTopPoint;
var offsetX,offsetY:Integer;
begin
GetCursorPos(FPointRec.LeftTop.NextP);
offsetX:=FPointRec.LeftTop.NextP.X-FPointRec.LeftTop.PrevP.X;
offSetY:=FPointRec.LeftTop.NextP.Y-FPointRec.LeftTop.PrevP.Y;
if not FisMoveStep then
begin
FPointRec.LeftTop.Left:=FPointRec.LeftTop.Left+offsetX;
FPointRec.LeftTop.Top:=FPointRec.LeftTop.Top+offsetY;
end
else begin
MoveX:=MoveX+offsetX;
MoveY:=MoveY+offsetY;
if Abs(moveX)>=FMoveStep then
begin
FPointRec.LeftTop.Left:=FPointRec.LeftTop.Left+moveX;
moveX:=0;
end;
if Abs(moveY)>=FMoveStep then
begin
FPointRec.LeftTop.Top:=FPointRec.LeftTop.Top+moveY;
moveY:=0;
end;
end;
FPointRec.LeftTop.PrevP:=FPointRec.LeftTop.NextP;
AlignLeftTop;
end;
//其他点对齐左右点
procedure TDragClass.AlignLeftTop;
begin
FPointRec.LeftBottom.Left:=FPointRec.LeftTop.Left;
FPointRec.RightTop.Top:=FPointRec.LeftTop.Top;
FPointRec.LeftMid.Left:=FPointRec.LeftTop.Left;
FPointRec.LeftMid.Top:=
(FPointRec.LeftBottom.Top+FPointRec.LeftTop.Top) div 2;
FPointRec.TopMid.Top:=FPointRec.LeftTop.Top;
FPointRec.TopMid.Left:=
(FPointRec.RightTop.Left+FPointRec.LeftTop.Left) div 2;
FPointRec.RightMid.Top:=
(FPointRec.RightTop.Top+FPointRec.RightButton.Top) div 2;
FPointRec.ButtonMid.Left:=
(FPointRec.LeftBottom.Left+FPointRec.RightButton.Left) div 2;
end;
//对齐点
procedure TDragClass.AlignLeftBottom;
begin
FPointRec.LeftTop.Left:=FPointRec.LeftBottom.Left;
FPointRec.RightButton.Top:=FPointRec.LeftBottom.Top;
FPointRec.LeftMid.Left:=FPointRec.LeftTop.Left;
FPointRec.LeftMid.Top:=
(FPointRec.LeftBottom.Top+FPointRec.LeftTop.Top) div 2;
FPointRec.TopMid.Top:=FPointRec.LeftTop.Top;
FPointRec.TopMid.Left:=
(FPointRec.RightTop.Left+FPointRec.LeftTop.Left) div 2;
FPointRec.RightMid.Top:=
(FPointRec.RightTop.Top+FPointRec.RightButton.Top) div 2;
FPointRec.ButtonMid.Top:=FPointrec.LeftBottom.Top;
FPointRec.ButtonMid.Left:=
(FPointRec.LeftBottom.Left+FPointRec.RightButton.Left) div 2;
end;
//移动左底点
procedure TDragClass.MoveLeftBottomPoint;
var offsetX,offsetY:Integer;
begin
GetCursorPos(FPointRec.LeftBottom.NextP);
offsetX:=FPointRec.LeftBottom.NextP.X-FPointRec.LeftBottom.PrevP.X;
offSetY:=FPointRec.LeftBottom.NextP.Y-FPointRec.LeftBottom.PrevP.Y;
if not FisMoveStep then
begin
FPointRec.LeftBottom.Left:=FPointRec.LeftBottom.Left+offsetX;
FPointRec.LeftBottom.Top:=FPointRec.LeftBottom.Top+offsetY;
end
else begin
MoveX:=MoveX+offsetX;
MoveY:=MoveY+offsetY;
if Abs(moveX)>=FMoveStep then
begin
FPointRec.LeftBottom.Left:=FPointRec.LeftBottom.Left+moveX;
moveX:=0;
end;
if Abs(moveY)>=FMoveStep then
begin
FPointRec.LeftBottom.Top:=FPointRec.LeftBottom.Top+moveY;
movey:=0;
end;
end;
FPointRec.LeftBottom.PrevP:=FPointRec.LeftBottom.NextP;
AlignLeftBottom;
end;
//对齐点
procedure TDragClass.AlignRightTop;
begin
FPointRec.LeftTop.Top:=FPointRec.RightTop.top;
FPointRec.RightButton.Left:=FPointRec.RightTop.Left;
FPointRec.LeftMid.Left:=FPointRec.LeftTop.Left;
FPointRec.LeftMid.Top:=
(FPointRec.LeftBottom.Top+FPointRec.LeftTop.Top) div 2;
FPointRec.TopMid.Top:=FPointRec.LeftTop.Top;
FPointRec.TopMid.Left:=
(FPointRec.RightTop.Left+FPointRec.LeftTop.Left) div 2;
FPointRec.RightMid.Left:=FPointRec.RightTop.Left;
FPointRec.RightMid.Top:=
(FPointRec.RightTop.Top+FPointRec.RightButton.Top) div 2;
FPointRec.ButtonMid.Top:=FPointrec.LeftBottom.Top;
FPointRec.ButtonMid.Left:=
(FPointRec.LeftBottom.Left+FPointRec.RightButton.Left) div 2;
end;
//移动右上点
procedure TDragClass.MoveRightTopPoint;
var offsetX,offsetY:Integer;
begin
GetCursorPos(FPointRec.RightTop.NextP);
offsetX:=FPointRec.RightTop.NextP.X-FPointRec.RightTop.PrevP.X;
offSetY:=FPointRec.RightTop.NextP.Y-FPointRec.RightTop.PrevP.Y;
if not FisMoveStep then
begin
FPointRec.RightTop.Left:=FPointRec.RightTop.Left+offsetX;
FPointRec.RightTop.Top:=FPointRec.RightTop.Top+offsetY;
end
else begin
MoveX:=MoveX+offsetX;
MoveY:=MoveY+offsetY;
if Abs(moveX)>=FMoveStep then
begin
FPointRec.RightTop.Left:=FPointRec.RightTop.Left+moveX;
moveX:=0;
end;
if Abs(moveY)>=FMoveStep then
begin
FPointRec.RightTop.Top:=FPointRec.RightTop.Top+moveY;
moveY:=0;
end;
end;
FPointRec.RightTop.PrevP:=FPointRec.RightTop.NextP;
AlignRightTop;
end;
//对齐点
procedure TDragClass.AlignRightBottom;
begin
FPointRec.LeftBottom.Top:=FPointRec.RightButton.top;
FPointRec.RightTop.Left:=FPointRec.RightButton.Left;
FPointRec.LeftMid.Left:=FPointRec.LeftTop.Left;
FPointRec.LeftMid.Top:=
(FPointRec.LeftBottom.Top+FPointRec.LeftTop.Top) div 2;
FPointRec.TopMid.Top:=FPointRec.LeftTop.Top;
FPointRec.TopMid.Left:=
(FPointRec.RightTop.Left+FPointRec.LeftTop.Left) div 2;
FPointRec.RightMid.Left:=FPointRec.RightTop.Left;
FPointRec.RightMid.Top:=
(FPointRec.RightTop.Top+FPointRec.RightButton.Top) div 2;
FPointRec.ButtonMid.Top:=FPointrec.LeftBottom.Top;
FPointRec.ButtonMid.Left:=
(FPointRec.LeftBottom.Left+FPointRec.RightButton.Left) div 2;
end;
//移动右底点
procedure TDragClass.MoveRightBottomPoint;
var offsetX,offsetY:Integer;
begin
GetCursorPos(FPointRec.RightButton.NextP);
offsetX:=FPointRec.RightButton.NextP.X-FPointRec.RightButton.PrevP.X;
offSetY:=FPointRec.RightButton.NextP.Y-FPointRec.RightButton.PrevP.Y;
if not FisMoveStep then
begin
FPointRec.RightButton.Left:=FPointRec.RightButton.Left+offsetX;
FPointRec.RightButton.Top:=FPointRec.RightButton.Top+offsetY;
end
else begin
MoveX:=MoveX+offsetX;
MoveY:=MoveY+offsetY;
if Abs(moveX)>=FMoveStep then
begin
FPointRec.RightButton.Left:=FPointRec.RightButton.Left+moveX;
moveX:=0;
end;
if Abs(moveY)>=FMoveStep then
begin
FPointRec.RightButton.Top:=FPointRec.RightButton.Top+moveY;
moveY:=0;
end;
end;
FPointRec.RightButton.PrevP:=FPointRec.RightButton.NextP;
AlignRightBottom;
end;
//对齐点
procedure TDragClass.AlignLeftMid;
begin
FPointRec.LeftTop.Left:=FPointRec.LeftMid.Left;
FPointRec.LeftBottom.Left:=FPointRec.LeftMid.Left;
FPointRec.TopMid.Top:=FPointRec.LeftTop.Top;
FPointRec.TopMid.Left:=
(FPointRec.RightTop.Left+FPointRec.LeftTop.Left) div 2;
FPointRec.ButtonMid.Top:=FPointrec.LeftBottom.Top;
FPointRec.ButtonMid.Left:=
(FPointRec.LeftBottom.Left+FPointRec.RightButton.Left) div 2;
end;
//左中点
procedure TDragClass.MoveLeftMidPoint;
var offsetX:Integer;
begin
GetCursorPos(FPointRec.LeftMid.NextP);
offsetX:=FPointRec.LeftMid.NextP.X-FPointRec.LeftMid.PrevP.X;
if not FisMoveStep then
begin
FPointRec.LeftMid.Left:=FPointRec.LeftMid.Left+offsetX;
end
else begin
MoveX:=MoveX+offsetX;
if Abs(moveX)>=FMoveStep then
begin
FPointRec.LeftMid.Left:=FPointRec.LeftMid.Left+moveX;
moveX:=0;
end;
end;
FPointRec.LeftMid.PrevP:=FPointRec.LeftMid.NextP;
AlignLeftMid;
end;
//对齐点
procedure TDragClass.AlignTopMid;
begin
FPointRec.LeftTop.Top:=FPointRec.TopMid.Top;
FPointRec.RightTop.Top:=FPointRec.TopMid.Top;
FPointRec.TopMid.Top:=FPointRec.LeftTop.Top;
FPointRec.LeftMid.Left:=FPointRec.LeftTop.Left;
FPointRec.LeftMid.Top:=
(FPointRec.LeftBottom.Top+FPointRec.LeftTop.Top) div 2;
FPointRec.RightMid.Left:=FPointRec.RightTop.Left;
FPointRec.RightMid.Top:=
(FPointRec.RightTop.Top+FPointRec.RightButton.Top) div 2;
end;
//顶中点
procedure TDragClass.MoveTopMidPoint;
var offsetY:Integer;
begin
GetCursorPos(FPointRec.TopMid.NextP);
offSetY:=FPointRec.TopMid.NextP.Y-FPointRec.TopMid.PrevP.Y;
if not FisMoveStep then
begin
FPointRec.TopMid.Top:=FPointRec.TopMid.Top+offsetY;
end
else begin
MoveY:=MoveY+offsetY;
if Abs(moveY)>=FMoveStep then
begin
FPointRec.TopMid.Top:=FPointRec.TopMid.Top+moveY;
moveY:=0;
end;
end;
FPointRec.TopMid.PrevP:=FPointRec.TopMid.NextP;
AlignTopMid;
end;
//对齐点
procedure TDragClass.AlignRightMid;
begin
FPointRec.RightTop.Left:=FPointRec.RightMid.Left;
FPointRec.RightButton.Left:=FPointRec.RightMid.Left;
FPointRec.TopMid.Top:=FPointRec.LeftTop.Top;
FPointRec.TopMid.Left:=
(FPointRec.RightTop.Left+FPointRec.LeftTop.Left) div 2;
FPointRec.ButtonMid.Top:=FPointrec.LeftBottom.Top;
FPointRec.ButtonMid.Left:=
(FPointRec.LeftBottom.Left+FPointRec.RightButton.Left) div 2;
end;
//右中点
procedure TDragClass.MoveRightMidPoint;
var offsetX:Integer;
begin
GetCursorPos(FPointRec.RightMid.NextP);
offsetX:=FPointRec.RightMid.NextP.X-FPointRec.RightMid.PrevP.X;
if not FisMoveStep then
begin
FPointRec.RightMid.Left:=FPointRec.RightMid.Left+offsetX;
end
else begin
MoveX:=MoveX+offsetX;
if Abs(moveX)>=FMoveStep then
begin
FPointRec.RightMid.Left:=FPointRec.RightMid.Left+moveX;
moveX:=0;
end;
end;
FPointRec.RightMid.PrevP:=FPointRec.RightMid.NextP;
AlignRightMid;
end;
//对齐点
procedure TDragClass.AlignBottomMid;
begin
FPointRec.LeftBottom.Top:=FPointRec.ButtonMid.Top;
FPointRec.RightButton.Top:=FPointrec.ButtonMid.Top;
FPointRec.LeftMid.Left:=FPointRec.LeftTop.Left;
FPointRec.LeftMid.Top:=
(FPointRec.LeftBottom.Top+FPointRec.LeftTop.Top) div 2;
FPointRec.RightMid.Left:=FPointRec.RightTop.Left;
FPointRec.RightMid.Top:=
(FPointRec.RightTop.Top+FPointRec.RightButton.Top) div 2;
end;
//底中点
procedure TDragClass.MoveBottomMidPoint;
var offsetY:Integer;
begin
GetCursorPos(FPointRec.ButtonMid.NextP);
offSetY:=FPointRec.ButtonMid.NextP.Y-FPointRec.ButtonMid.PrevP.Y;
if not FisMoveStep then
begin
FPointRec.ButtonMid.Top:=FPointRec.ButtonMid.Top+offsetY;
end
else begin
MoveY:=MoveY+offsetY;
if Abs(moveY)>=FMoveStep then
begin
FPointRec.ButtonMid.Top:=FPointRec.ButtonMid.Top+moveY;
moveY:=0;
end;
end;
FPointRec.ButtonMid.PrevP:=FPointRec.ButtonMid.NextP;
AlignBottomMid;
end;
//重定位控件的尽寸
procedure TDragClass.reSizeCon;
var Con:TControl;
begin
Con:=TControl(FConList.Items[FCurActiveCon]);
Con.Left:=FPointRec.LeftTop.Left+FPointRec.LeftTop.Width;
Con.Top:=FPointRec.LeftTop.Top+FPointRec.LeftTop.Height;
Con.Width:=FPointRec.RightTop.Left-Con.Left;
Con.Height:=FPointRec.LeftBottom.Top-Con.Top;
end;
//-----------------------------------------------
//设置控件移动时是否用跳跃式的移动
procedure TDragClass.SetisMoveStep(value: Boolean);
begin
if FisMoveStep<>value then
FisMoveStep:=Value;
end;
//设置控件移动跳跃的距离
procedure TDragClass.SetMoveStep(value: integer);
begin
if Value<5 then
FMoveStep:=5
else if Value>20 then
FMoveStep:=20
else
FMoveStep:=Value;
end;
end.
到第三部分，用一个例子来说明这个类的用法
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