Class TDBBitwiseCheckBox (unit Bitwise) |
Inherits from
TLiteCheckBox
Bitwise components manipulate a single bit within a data field.
TDBBitwiseCheckBox works just like TDBCheckBox except that you also
specify a value; typically a power of 2 (1,2,4,8,16,32,.. 16384) If the
box is checked, that value is OR'd with the field's value. If the
box is unchecked, that value is NOT AND'd with the field's value.
This is set with CheckValue.
Caveat: the underlying data field MUST be an integer.
TDBBitwiseRadioButton works the same way except it looks like a radio
button. Here, since the "other" radio buttons in the group presumably
correspond to other enumerated values, the field is set to CheckValue
when the button is pressed. For example, you might have four radio
buttons with checkValues 1,2,3,4 to indicate one of four choices. For
the CheckBoxes, you would have one of four values 1,2,4,8 for the
sixteen possible permutations.
Caveat: the underlying data field MUST be an integer.
constructor Create( owner: TComponent );
- A change to the underlying data is reflected in the state of the checkbox.
destructor Destroy;
procedure KeyPress( var Key: Char );
procedure Notification( AComponent: TComponent; Operation: TOperation );
procedure Toggle;
procedure CMExit( var Message: TCMExit );
procedure DataChange( sender: TObject );
function GetDataField: String;
TDBBitwiseCheckBox
function GetDataSource: TDataSource;
procedure SetDataField( const value: String );
procedure SetDataSource( value: TDataSource );
procedure UpdateData( Sender: TObject );
property CheckValue : Integer
property DataField : String
property DataSource : TDataSource
property State :
FDataLink : TFieldDataLink;
myCheckValue : Integer;
constructor Create( owner: TComponent );
A change to the underlying data is reflected in the state of the checkbox.
destructor Destroy;
procedure KeyPress( var Key: Char );
procedure Notification( AComponent: TComponent; Operation: TOperation );
procedure Toggle;
procedure CMExit( var Message: TCMExit );
procedure DataChange( sender: TObject );
function GetDataField: String;
TDBBitwiseCheckBox
function GetDataSource: TDataSource;
procedure SetDataField( const value: String );
procedure SetDataSource( value: TDataSource );
procedure UpdateData( Sender: TObject );
property CheckValue : Integer
property DataField : String
property DataSource : TDataSource
property State :
FDataLink : TFieldDataLink;
myCheckValue : Integer;