blob: 10f0e5a67baaced84d4e03044e99667ff8d5d5f3 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
{
fpGUI - Free Pascal Graphical User Interface
Copyright (C) 2000 - 2001 by
Areca Systems GmbH / Sebastian Guenther
Copyright (C) 2006 by Graeme Geldenhuys
member of the fpGUI development team.
fgGUI database support
See the file COPYING.fpGUI, included in this distribution,
for details about the copyright.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
**********************************************************************}
unit fpGUI_DB;
{$IFDEF Debug}
{$ASSERTIONS On}
{$ENDIF}
interface
uses Classes, fpGUI, DB;
type
TFieldDataLink = class(TDataLink)
private
FWidget: TWidget;
FField: TField;
FFieldName: String;
FOnDataChange: TNotifyEvent;
procedure SetFieldName(const AFieldName: String);
procedure UpdateField;
protected
procedure ActiveChanged; override;
procedure RecordChanged(AField: TField); override;
public
constructor Create(AWidget: TWidget);
property Field: TField read FField;
property FieldName: String read FFieldName write SetFieldName;
property OnDataChange: TNotifyEvent read FOnDataChange write FOnDataChange;
end;
TDBText = class(TCustomLabel)
private
FDataLink: TFieldDataLink;
function GetDataField: String;
procedure SetDataField(const ADataField: String);
function GetDataSource: TDataSource;
procedure SetDataSource(ADataSource: TDataSource);
procedure DataChange(Sender: TObject);
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
published
property Text;
property DataField: String read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
end;
// ===================================================================
// ===================================================================
implementation
constructor TFieldDataLink.Create(AWidget: TWidget);
begin
inherited Create;
FWidget := AWidget;
end;
procedure TFieldDataLink.ActiveChanged;
begin
UpdateField;
end;
procedure TFieldDataLink.RecordChanged(AField: TField);
begin
if Assigned(OnDataChange) then
OnDataChange(Self);
end;
procedure TFieldDataLink.SetFieldName(const AFieldName: String);
begin
if AFieldName <> FieldName then
begin
FFieldName := AFieldName;
UpdateField;
end;
end;
procedure TFieldDataLink.UpdateField;
begin
WriteLn('##############UpdateField. DataSet: ', DataSource.DataSet.ClassName);
FField := DataSource.DataSet.FindField(FieldName);
if Assigned(OnDataChange) then
OnDataChange(Self);
end;
constructor TDBText.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
FDataLink := TFieldDataLink.Create(Self);
FDataLink.OnDataChange := @DataChange;
end;
destructor TDBText.Destroy;
begin
FDataLink.Free;
inherited Destroy;
end;
function TDBText.GetDataField: String;
begin
Result := FDataLink.FieldName;
end;
procedure TDBText.SetDataField(const ADataField: String);
begin
FDataLink.FieldName := ADataField;
end;
function TDBText.GetDataSource: TDataSource;
begin
Result := FDataLink.DataSource;
end;
procedure TDBText.SetDataSource(ADataSource: TDataSource);
begin
FDataLink.DataSource := ADataSource;
end;
procedure TDBText.DataChange(Sender: TObject);
begin
Write('TDBText.DataChange');
if Assigned(FDataLink.Field) then
begin
Text := FDataLink.Field.DisplayText;
WriteLn(' new text: "', Text, '"');
end else
begin
Text := '';
WriteLn('DataLink has no data');
end;
end;
end.
{
$Log: fpgui_db.pp,v $
Revision 1.2 2001/01/17 21:36:26 sg
* Updating fixes
Revision 1.1 2000/12/23 23:20:16 sg
* First public CVS version...
}
|