如何实现将图片周围可以调整大小的控件？

Question

如何实现将图片周围可以调整大小的控件？
就是在图象周围可以调整大小，需要动态的创建。

Answer 1

PHOTOSHOP不是有个功能吗？当你选取一个图片的某一部分的时候在选取的图片周围出现可以调节大小，表现为选择图片周围出现小箭头调整。

Answer 2

试试这个，程序中可能还有一些问题，欢迎交流：[email protected]
/////代码////////////
unit Graphic;interfaceuses
  Windows, Messages, SysUtils, Classes, Controls,Graphics;type
  TGraphic = class(TGraphicControl)
  private
    { Private declarations }
    FPicFile:string;
    X1,Y1,X2,Y2:integer;
    FDragKind:TDragKind;
    FDragMode:TDragMode;
    Selected:Boolean;
    DragState:Integer;
    DragX,DragY:integer;
    H,W:integer;
//    S1,s2:String;
    procedure SetPicFile(Value:String);
    procedure SetDragKind(Value:TDragKind);
//    procedure SetDragMode(Value:TDragMode);
  protected
    { Protected declarations }
    procedure Paint; override;
    procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Integer); override;
    procedure MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);override;
    procedure MouseMove(Shift: TShiftState; X, Y: Integer);override;
  public
    { Public declarations }
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
  published
    { Published declarations }
    property PicFile:string read FPicFile write SetPicFile;
    property DragKind:TDragKind read FDragKind write SetDragKind;
    property DragMode:TDragMode read FDragMode write SetDragMode;    property OnMouseDown;
    property OnMouseUp;
    property OnMouseMove;  end;      procedure Register;implementationprocedure TGraphic.SetDragKind(Value:TDragKind);
begin
 FDragKind:=value;
 Invalidate;
end;

Answer 3

function Between(x,x1,x2:integer):boolean;
begin
 if (x>=x1) and (x<=x2)  then
    Between:=true
  else
    Between:=false;
end;procedure TGraphic.MouseMove(Shift: TShiftState; X, Y: Integer);
 var p:TPoint;
begin
    GetCurSorPos(p);
    p:=ScreenToClient(p);
 //   S2:='X:' +inttostr(P.x)+'   Y:'+Inttostr(p.y);
    if selected then
    begin
     cursor:= crArrow;
  //   DragState:=0;
  if between(x,0,6) then
   begin
    if between(y,0,6) then  //左上角
     begin
      cursor:= crSizeNWSE;
      DragState:=1;
     end;
    if between(y,round(height/2)-3,round(height/2)+3) then //中左
     begin
      cursor:= crSizeWE;
      DragState:=2;
     end;
    if between(y,height-6,height) then   //左下角
     begin
      cursor:= crSizeNESW;
      DragState:=3;
     end;
   end;
   if between(x,round(width/2)-3,round(width/2)+3) then
    begin
     if between(y,0,6) then //中上
      begin
       cursor:= crSizeNS;
       DragState:=4;
      end;
     if between(y,height-6,height) then   //中下
      begin
       cursor:= crSizeNS;
       DragState:=5;
      end;
    end;
   if between(x,width-6,width) then
    begin
     if between(y,0,2) then    //右上角
      begin
       cursor:= crSizeNESW;
       DragState:=6;
      end;
     if between(y,round(height/2)-3,round(height/2)+3) then //中右
      begin
       cursor:= crSizeWE;
       DragState:=7;
      end;
     if between (y,height-6,height) then  //右下角
      begin
       cursor:= crSizeNWSE;
       DragState:=8;
      end;
   end;
    end;
//    Invalidate;
end;procedure TGraphic.SetPicFile(Value:string) ;
begin
   FPicFile:=value;
   Invalidate;
end;procedure TGraphic.MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
 var P:TPoint;
begin
 GetCurSorPos(p);
 p:=ScreenToClient(p);
 case  DragState of
   0:    //拖动
    begin
     top:=Y1+(p.Y-DragY);
     Left:=X1+(p.X-DragX);
    end;
   1:    //左上角
    begin
     if p.y>h then
      top:=y1+p.y+H-p.y
     else
      top:=y1+p.y;
     if p.x>W then
      left:=x1+p.x+W-p.X
     else
      left:=x1+p.x;
     height:=abs(H-p.y);
     width:=abs(w-p.X);
    end;
   2:   //中左
    begin
     top:=y1;
     if p.x<w then
        left:=x1+p.X
      else
        left:=x2;  
     height:=h;
     width:=abs(p.X-w);
    end;
   3:   //左下角
    begin
     if p.x>W then
      left:=x2//-w//x1-p.x-W     //here have problem=
     else
      left:=x1+p.x;
     if p.y<0 then
      top:=y1+p.Y
     else
      top:=y1;//x1+p.x;
     if p.y<0 then
      height:=abs(p.Y)
     else
      height:=abs(p.Y);
     width:=abs(w-p.X);
    end;
   4:  //中上
    begin
     left:=x1;
     if p.y<H then
        top:=y1+p.y
      else
        top:=y2;
     height:=abs(p.Y-h);
     width:=w;
    end;
   5:  //中下
    begin
     left:=x1;
     if p.y<0 then
        top:=y1+p.y
      else
        top:=y1;
     if p.y<0 then
        height:= abs(p.y)
      else
        height:=p.Y ; 
     width:=w;
    end;
   6: //右上角
    begin
     if p.x>0 then
      left:=x1
     else
      left:=(x1+p.X);
     if p.y>H then
      top:=y2
     else
      top:=y1+p.Y;
     height:=abs(h-p.Y);
     width:=abs(p.X);
     
    end;
   7: //中右
    begin
     if p.x>0 then
      left:=x1
     else
      left:=abs(x1+p.X);
     top:=y1;
     height:=h;
     if p.x>0 then
      width:=p.X
     else
      width:= abs(p.X);
    end;
   8: //右下角
    begin
     top:=y1;
     if p.x>0 then
      left:=x1
     else
      left:=abs(x1+p.x);
      
     width:=abs(p.X);
     height:=abs(p.y);
    end;
 end;
end;procedure TGraphic.MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
 var P:TPoint;
begin
  Selected:=true;
  DragState:=0;
  if between(x,0,6) then
   begin
    if between(y,0,6) then  //左上角
     begin
      cursor:= crSizeNWSE;
      DragState:=1;
     end;
    if between(y,round(height/2)-3,round(height/2)+3) then //中左
     begin
      cursor:= crSizeWE;
      DragState:=2;
     end;
    if between(y,height-6,height) then   //左下角
     begin
      cursor:= crSizeNESW;
      DragState:=3;
     end;
   end;
   if between(x,round(width/2)-3,round(width/2)+3) then
    begin
     if between(y,0,6) then //中上
      begin
       cursor:= crSizeNS;
       DragState:=4;
      end;
     if between(y,height-6,height) then   //中下
      begin
       cursor:= crSizeNS;
       DragState:=5;
      end;
    end;
   if between(x,width-6,width) then
    begin
     if between(y,0,2) then    //右上角
      begin
       cursor:= crSizeNESW;
       DragState:=6;
      end;
     if between(y,round(height/2)-3,round(height/2)+3) then //中右
      begin
       cursor:= crSizeWE;
       DragState:=7;
      end;
     if between (y,height-6,height) then  //右下角
      begin
       cursor:= crSizeNWSE;
       DragState:=8;
      end;
   end;//   Top1:=top;
//   left1:=left;
//  height1:=height;
//   width1:=width;
   GetCurSorPos(p);
   p:=ScreenToClient(p);
   DragX:=p.X;
   DragY:=p.Y;
   X1:=left;//p.x;
   Y1:=top;//p.y;
   X2:=X1+Width;
   Y2:=Y1+Height;
   H:=Height;
   W:=Width;
end;procedure TGraphic.Paint ;
  var Bitmap : TBitMap;
  //    BitRect:TRect;
      ARect: TRect;
begin
  with inherited Canvas do
    begin
     Brush.Style := bsSolid;
     brush.Color :=clWhite;
   //  brush.
     //Rectangle(0,0,width,height);
     Rectangle(2,2,width-2,height-2);
   //  textout(100,100,s1);
   //  textout(100,120,S2);
     if fileexists(PicFile) then
      begin
//       Bitmap := TBitmap.Create;
//       bitmap.LoadFromFile(PicFile);
       ARect := Rect(0,0,width,height);
       ARect.Left := 0;
       ARect.Top := 0;
       Bitmap := TBitmap.Create;
       bitmap.LoadFromFile(PicFile);
       Canvas.Brush.Bitmap := Bitmap;
       Canvas.FillRect(ARect);
       Canvas.StretchDraw(ARect,Bitmap);   //    bitrect.Left :=0;
   //    bitrect.Top :=0;
   //    bitrect.Right:=width;
   //    bitrect.Bottom :=height;
     //  bitmap.Canvas.StretchDraw(Rect(0,0,width-1,height-1),picfile);
      canvas.StretchDraw(rect(0,0,Width,Height),bitmap );
  //    CopyRect(rect(0,0,Width,Height),bitmap.Canvas,rect(0,0,bitmap.Width,bitmap.Height) );
//         with Image.Canvas do
 // begin
 //   CopyMode := cmWhiteness;
 //   ARect := Rect(0, 0, Image.Width, Image.Height);
  //  CopyRect(ARect, Image.Canvas, ARect);
  //  CopyMode := cmSrcCopy; { restore the copy mode }
   //    bitmap.Transparent:= True;
    //   bitmap.TransParentColor := BitMap.Canvas.Brush.Color;
    //   bitmap.TransparentMode := tmAuto;
//       bitmap.
     //  Draw(0,0,BitMap);
      end;   if selected then
    begin
     Brush.Style := bsSolid;
     brush.Color :=clBlack;
     canvas.FillRect(rect(0,0,6,6));     //左上角
     canvas.FillRect(rect(width-6,0,width,6));      //右上角
     canvas.FillRect(rect(0,height-6,6,height));       //左下角
     canvas.FillRect(rect(width-6,height-6,width,height));     //右下角
     canvas.FillRect(rect(Round(width/2)-3,0,Round(width/2)+3,6));  //中上
     canvas.FillRect(rect(Round(width/2)-3,height-6,Round(width/2)+3,height)); //中下
     canvas.FillRect(rect(0,Round(height/2)-3,6,Round(height/2)+3));     //中左
     canvas.FillRect(rect(width-6,Round(height/2)-3,width+3,Round(height/2)+3)) //中右
    end;
  end;
end;constructor TGraphic.Create(AOwner: TComponent);
begin
  inherited Create (AOwner);
 // ZoomMode:=0;
  DragState:=0;
  Selected:=false;
end;destructor TGraphic.Destroy;
begin
  inherited Destroy;
end;procedure Register;
begin
  RegisterComponents('Samples', [TGraphic]);
end;end.

Answer 4

to: zytao
这段代码工作得很好,但是为什么移动速度比较慢
另外，如果希望移动和改变大小的时候有一个虚线框该如何实现呢？