[Overview][Constants][Types][Classes][Procedures and functions][Index] Reference for unit 'StdCtrls' (#lcl)

TComboBox

[Properties (by Name)] [Methods (by Name)] [Events (by Name)]

TComboBox - a simple combination of text box for free text entry, and a drop-down list allowing one of several options to be chosen.

Declaration

Source position: stdctrls.pp line 407

type TComboBox = class(TCustomComboBox)

published

  property Align;

  

Used to align the control to the top, bottom, left or right of its client.

  property Anchors;

  

The set of anchor definitions for this control

  property ArrowKeysTraverseList;

  

ArrowKeysTraverseList - enables the operator to use the keyboard Arrow keys to move through the list as an alternative to using the mouse

  property AutoComplete;

  

AutoComplete - enables the facility to offer suggestions for completing text-strings

  property AutoCompleteText;

  

AutoCompleteText : Options for behavior of the Auto-Complete feature

  property AutoDropDown;

  

AutoDropDown - if True, the drop-down list appears as soon as the cursor moves over the text box

  property AutoSelect;

  

AutoSelect : Boolean. If True, all contents of Text box are selected when control receives focus

  property AutoSize;

  

Whether auto-size is to be used

  property BidiMode;

  

BiDiMode - enabling bi-directional writing

  property BorderSpacing;

  

Determines the border spacing for this control

  property CharCase;

  

CharCase: indicates whether text is to be displayed as Upper, Lower or Normal case (as entered)

  property Color;

  

Determine the colour for the current control

  property Constraints;

  

Determine Constraints (max and min height and width) for this control

  property DragCursor;

  

DragCursor - the style of cursor to be used during the Drag process

  property DragKind;

  property DragMode;

  

DragMode - whether manual or automatic

  property DropDownCount;

  

DropDownCount - number of entries in the drop-down list

  property Enabled;

  

Whether the control is Enabled (read/write). If not, it usually appears 'greyed-out'

  property Font;

  

The font to be used for text in this control (read/write).

  property ItemHeight;

  

ItemHeight - the height of the current item in the drop-down list

  property ItemIndex;

  

Index - the number of the currently selected item (starting at zero)

  property Items;

  

Items - an array of strings that holds the entries of the drop-down list

  property ItemWidth;

  

ItemWidth - the width of the current item in the drop-down list

  property MaxLength;

  

MaxLength - the maximum allowed length of a string

  property OnChange;

  

OnChange - event handler for any change in properties of the combo box

  property OnChangeBounds;

  

Event handler for a change in bounds of the control

  property OnClick;

  

Event Handler for mouse click

  property OnCloseUp;

  

OnCloseUp - event handler for when the drop-down box is closed up again

  property OnContextPopup;

  

Event handler to supply information when a context-sensitive pop-up menu is required

  property OnDblClick;

  

Event Handle for mouse double-click

  property OnDragDrop;

  

Event handler for the drop of a control onto this control.

  property OnDragOver;

  

Event handler for the case when a control is dragged over another control

  property OnDrawItem;

  

OnDrawItem - event handler for when an entry is written to the Items list

  property OnEndDrag;

  

Event handler for the end of a dragging process

  property OnDropDown;

  

  property OnEditingDone;

  

Event handler when editing is done

  property OnEnter;

  

OnEnter - event handler for when the mouse enters the control, and the control receives focus

  property OnExit;

  

OnExit - event handler for when the mouse leaves the control and it loses focus

  property OnGetItems;

  

OnGetItems - event handler for getting list of items for dropdown box

  property OnKeyDown;

  

OnKeyDown - event handler for instance when key is down while control has focus

  property OnKeyPress;

  

OnKeyPress - event controller for a key being pressed while the control has focus. To properly handle national chars use UTF8KeyPress instead.

  property OnKeyUp;

  

OnKeyUp - event handler for instance when a key is up (not pressed) while the control has focus

  property OnMeasureItem;

  

Event handler when measurement of an item is required

  property OnMouseDown;

  

Event handler for when a mouse button is pressed down

  property OnMouseEnter;

  property OnMouseLeave;

  property OnMouseMove;

  

Event handler for mouse movement within the current control

  property OnMouseUp;

  

Event handler for when the mouse button is released, ie "up"

  property OnStartDrag;

  

Event handler for start of dragging operation

  property OnSelect;

  

Event handler when an item or some text is selected

  property OnUTF8KeyPress;

  

UTF8KeyPress - event controller for a key being pressed while the control has focus.

  property ParentBidiMode;

  

ParentBiDiMode - does the control follow the BiDiMode settings of its parent?

  property ParentColor;

  

ParentColor - should the control have the same colour as the parent? Default is true

  property ParentFont;

  

ParentFont - should the control use the same font as the parent? Default is true

  property ParentShowHint;

  

ParentShowHint - does the control adopt the same hinting behaviour as its parent? Default is true

  property PopupMenu;

  

PopupMenu - a context-sensitive menu that pops up when the right mouse button is clicked over this control

  property ReadOnly;

  

ReadOnly - if True, information in the control can only be Read, not Written or Deleted

  property ShowHint;

  

Flag to determine: Is hint to be displayed for this control?

  property Sorted;

  

Sorted - whether the entries in the drop-down list have been sorted

  property Style;

  

Style : may be Simple, a single-line Drop-Down or a Drop-Down list, or some version drawn by the Owner

  property TabOrder;

  

The place this control occupies in the list of tabs

  property TabStop;

  

Is the control in the sequence of controls accessed by successive presses of the Tab key?

  property Text;

  

Text - the string appearing in the main box. If an item on the drop-down list is selected, it replaces the contents of Text

  property Visible;

  

Visible - can the control be seen?

end;

Inheritance

TComboBox

  

TComboBox - a simple combination of text box for free text entry, and a drop-down list allowing one of several options to be chosen.

|

TCustomComboBox

  

TCustomComboBox - the base class from which TComboBox is derived

|

TWinControl

|

TControl

|

TLCLComponent

  

TLCLComponent - base class for LCL components

|

TComponent,IUnknown,IInterfaceComponentReference

|

TPersistent

|

TObject

Description

TComboBox - a simple combination of text box for free text entry, and a drop-down list allowing one of several options to be chosen.

The default text-string (if any, entered in the Form Designer) and the value of the text string that is ultimately selected from the drop-down list, is held in Text

The values that can be selected from the drop-down list are held in the string-array Items. Clicking on the ellipsis (...) next to Items in the Object Inspector opens a pop-up string-list editor which allows the designer to enter and edit a number of lines of text to represent the selections

At run-time, the entry selected from the drop-down list in Items is used to replace any information previously found in Text, and ItemIndex holds the (zero-origin) index number of the selected item

If no value is selected from the drop-down list, the default text (if any) remains, or any information typed directly into Text will be returned, and ItemIndex takes the value of -1

See also

HowToUseStdCtrls

  

How to use StdCtrls, ComCtrls or ExtCtrls

The latest version of this document can be found at lazarus-ccr.sourceforge.net.