[Overview][Constants][Types][Classes][Procedures and functions][Index] |
[Properties (by Name)] [Methods (by Name)] [Events (by Name)]
TDBImage - a data-aware Image box to display a single image from a dataset
Source position: dbctrls.pp line 1042
type TDBImage = class(TCustomImage) end; |
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protected |
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procedure Notification(); override; |
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procedure DataChange(); |
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DataChange - if data changed, load new picture |
procedure UpdateData(); virtual; |
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UpdateData - if data changed, save new picture |
procedure PictureChanged(); override; |
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PictureChanged - software emulaton of the OnPictureChanged event |
procedure LoadPicture; virtual; |
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LoadPicture - loads picture into the appropriate field for the graphic class of the caller |
class procedure WSRegisterClass; override; |
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public |
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constructor Create(); override; |
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Create - constructor for TDBImage: cals inherited Create then sets style and display methods, forms datalinks and actions |
destructor Destroy; override; |
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Destroy - destructor for TDBImage: frees datalinks and calls inherited Destroy |
function ExecuteAction(); override; |
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function UpdateAction(); override; |
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property Field: TField; [r] |
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The Field in which picture data are stored |
procedure Change; virtual; |
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Change - if picture is changes, datalink needs to be informed |
published |
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Specifies the placement of the control inside its Parent. |
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The set of anchor definitions for this control. |
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property AutoDisplay: Boolean; [rw] |
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AutoDisplay - if True, automatically displays when focus is given |
property AutoSize: Boolean; |
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Allows to automatically adjust the size of the control, according to its content. |
property BorderSpacing: TControlBorderSpacing; |
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Determines the inner and outer border spacing for this control. |
property Center: Boolean; |
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Should image be centered? |
property Constraints: TSizeConstraints; |
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The minimal and maximal Width and Height of this control. |
property DataField: string; [rw] |
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The name of the DataField that holds the image |
property DataSource: TDataSource; [rw] |
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The identity of the DataSource that holds the image |
property DragCursor: TCursor; |
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The cursor shape shown while the control is dragged. |
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Allows the user to drag the control. |
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property OnClick: TNotifyEvent; |
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Notification handler for mouse clicks. |
property OnDblClick: TNotifyEvent; |
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property OnDBImageRead: TOnDBImageRead; [rw] |
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Event to read a custom header from image stream. |
property OnDBImageWrite: TOnDBImageWrite; [rw] |
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Event to write a custom header into image stream. |
property PopupMenu: TPopupMenu; |
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property OnDragDrop: TDragDropEvent; |
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This handler determines the action on an drop onto this control, in a drag-drop operation. |
property OnDragOver: TDragOverEvent; |
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Event handler for a control being dragged over this control. |
property OnEndDrag: TEndDragEvent; |
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Notification handler for the end of a dragging operation. |
property OnMouseDown: TMouseEvent; |
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Event handler for mouse button going down. |
property OnMouseEnter: TNotifyEvent; |
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property OnMouseLeave: TNotifyEvent; |
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property OnMouseMove: TMouseMoveEvent; |
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Event handler for mouse movement within the control. |
property OnMouseUp: TMouseEvent; |
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Event handler for mouse button going up. |
property OnMouseWheel: TMouseWheelEvent; |
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property OnMouseWheelDown: TMouseWheelUpDownEvent; |
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property OnMouseWheelUp: TMouseWheelUpDownEvent; |
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property OnStartDrag: TStartDragEvent; |
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Event handler for the start of a dragging operation. |
property Proportional: Boolean; |
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True if image is proportional |
property QuickDraw: Boolean; [rw] |
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QuickDraw - if True, quick drawing is implemented |
property ReadOnly: Boolean; [rw] |
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ReadOnly if True, image can be inspected byt not modified or written |
property Stretch: Boolean; |
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True if picture is to be stretched |
property Transparent: Boolean; |
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True if you can see through the image |
property Visible: Boolean; |
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Allows to show or hide the control, and all of its children. |
property WriteHeader: Boolean; [rw] |
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Write a header in the image stream. |
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TDBImage - a data-aware Image box to display a single image from a dataset |
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TCustomImage - the base type for TImage |
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TGraphicControl is the base class for all lightweight controls. |
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The base class for visible controls. |
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The base class for LCL components associated with widgets. |
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TComponent |
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TObject |
The Image is stored in the database as a Binary Large Object (BLOB)
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HowToUseDataAwareControls - Hints for accessing databases |
lazarus-ccr.sourceforge.net |