• Controls 属性与继承 TShape 类的小练习(使用TShape可以解决很多图形问题)


    本例效果图:



    代码文件:


    unit Unit1;
    
    interface
    
    uses
      Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
      Dialogs, StdCtrls, ExtCtrls;
    
    type
      TMyShape = class(TShape)
      protected
        procedure CMMouseenter(var Message: TMessage); message CM_MOUSEENTER;
        procedure CMMouseleave(var Message: TMessage); message CM_MOUSELEAVE;
      end;
    
      TForm1 = class(TForm)
        Panel1: TPanel;
        Button1: TButton;
        Button2: TButton;
        procedure Button1Click(Sender: TObject);
        procedure Button2Click(Sender: TObject);
      end;
    
    var
      Form1: TForm1;
    
    implementation
    
    {$R *.dfm}
    
    procedure TForm1.Button1Click(Sender: TObject);
    const
      W = 50;
      H = 50;
    var
      shape: TMyShape;
    begin
      shape := TMyShape.Create(Self);
      shape.Parent := Panel1;
      shape.Width := W;
      shape.Height := H;
      Randomize;
      shape.Left := Random(Panel1.ClientWidth - W);
      shape.Top := Random(Panel1.ClientHeight - H);
      shape.Brush.Color := Random($FFFFFF);
    end;
    
    procedure TForm1.Button2Click(Sender: TObject);
    var
      i: Integer;
    begin
      if Panel1.ControlCount = 0 then Exit;
      Randomize;
      i := Random(Panel1.ControlCount - 1);
      Panel1.Controls[i].Free;
    end;
    
    
    { TMyShape }
    
    procedure TMyShape.CMMouseenter(var Message: TMessage);
    const
      s = '当前 %s 的颜色值是: %.6x';
    var
      WCtrl: TWinControl;
    begin
      WCtrl := Parent;
      while WCtrl.HasParent do WCtrl := WCtrl.Parent;
      if WCtrl is TForm then TForm(WCtrl).Caption := Format(s, [ClassName,Brush.Color]);
      inherited;
    end;
    
    procedure TMyShape.CMMouseleave(var Message: TMessage);
    const
      s = 'Form1';
    var
      WCtrl: TWinControl;
    begin
      WCtrl := Parent;
      while WCtrl.HasParent do WCtrl := WCtrl.Parent;
      if WCtrl is TForm then TForm(WCtrl).Caption := s;
      inherited;
    end;
    
    end.

    http://www.cnblogs.com/del/archive/2008/10/23/1317926.html

  • 相关阅读:
    16-高级指针
    15-C语言结构体
    14-C语言宏
    13-C语言字符串函数库
    12-C语言字符串
    11-C语言指针
    10-C语言函数
    POJ 1001 高精度乘法
    POJ 1060 多项式乘法和除法取余
    POJ 1318 字典排序
  • 原文地址:https://www.cnblogs.com/findumars/p/6027554.html
Copyright © 2020-2023  润新知