Author: Marc Hoffmann
I would like to add some Windows' Taskbar-Buttons for dynamic created forms w/o
loosing the ability to 're-focus' the MainForm by clicking it's own button.
Answer:
The following example uses a Button (Button1)to dynamic create forms at runtime.
Each form will be accessable via a corresponding Button placed on the Taskbar. You
had to include the WMSysCommand method to enable the real "look&feel" of minimizing
the MainForm. Otherwise, the MainForm will be minimized to the lower left side of
the Screen or will be hidden in the background, so it's not possible to restore it
correctly.
If you want to minimize (or hide) all subforms when minimizing the MainForm, you
had to iterate through all registered subforms and hide them manualy. I don't know
a better way right now, but if you've found any solution...:-)
MainForm Unit
1 unit MainForm;
2
3 interface
4
5 uses
6 Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
7 StdCtrls;
8
9 type
10 TMainForm = class(TForm)
11 Button1: TButton;
12 procedure FormCreate(Sender: TObject);
13 procedure Button1Click(Sender: TObject);
14 private
15 { Private declarations }
16 procedure WMSysCommand(var Msg: TMessage); message WM_SYSCOMMAND;
17 public
18 { Public declarations }
19 procedure CreateParams(var Params:
20 TCreateParams); override;
21 end;
22
23 var
24 MainForm: TMainForm;
25
26 implementation
27
28 {$R *.DFM}
29
30 uses
31 SubForm;
32
33 var
34 SubForm: TSubForm;
35
36 procedure TMainForm.FormCreate(Sender: TObject);
37 begin
38 SetWindowLong(Application.Handle, GWL_EXSTYLE,
39 GetWindowLong(Application.Handle, GWL_EXSTYLE) or
40 WS_EX_TOOLWINDOW and not WS_EX_APPWINDOW);
41 end;
42
43 procedure TMainForm.CreateParams(var Params: TCreateParams);
44 begin
45 inherited CreateParams(Params);
46 Params.ExStyle := Params.ExStyle or WS_EX_APPWINDOW and not WS_EX_TOOLWINDOW;
47 end;
48
49 procedure TMainForm.WMSysCommand(var Msg: TMessage);
50 begin
51 DefaultHandler(Msg);
52 end;
53
54 procedure TMainForm.Button1Click(Sender: TObject);
55 begin
56 SubForm := TSubForm.Create(Application);
57 SubForm.Show;
58 end;
59
60 end.
61
62 //SubForm Unit
63
64 unit SubForm;
65
66 interface
67
68 uses
69 Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;
70
71 type
72 TSubForm = class(TForm)
73 procedure FormClose(Sender: TObject; var Action: TCloseAction);
74 private
75 { Private declarations }
76 public
77 { Public declarations }
78 procedure CreateParams(var Params: TCreateParams); override;
79 end;
80
81 implementation
82
83 {$R *.DFM}
84
85 procedure TSubForm.CreateParams(var Params: TCreateParams);
86 begin
87 inherited CreateParams(Params);
88 Params.ExStyle := Params.ExStyle or WS_EX_APPWINDOW;
89 end;
90
91 procedure TSubForm.FormClose(Sender: TObject; var Action: TCloseAction);
92 begin
93 Action := caFree;
94 end;
95
96 end.
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