The Listbox control is used to display tabular data. You can create list boxes which look like spreadsheet grids, perform drag-and-drop tasks, and more.
This section only discusses placing the listbox. After you place a listbox, you must format it.
See the List Box Formatter dialog for more information on formatting and adding additional functionality to your list boxes.
The Property View presents you with two ways to view a control's properties.
This help documents displays the properties in the categorical view.
Enter a valid color equate in the TextColor, Background, SelForeGround, SelBackground, or GridColor fields, or press the ellipsis (…) button to select a color from the Color dialog. The Window Designer adds the COLOR attribute to your control declaration.
See ..\LIBSRC\EQUATES.CLW for a list of valid color equates. See Windows Design Issues in the User's Guide for a discussion on using color to enhance your application.
Design settings control visual elements you see in the Window Designer. These settings should not affect the window display at runtime.
|Locked||“Freezes” the control so that subsequent data dictionary changes are not applied. You can override the #Freeze attribute for all controls or for individual controls. See Application Options.|
|Tab Index||Determines the index in the TAB order that this control will follow. The first tab in the order is index zero (0).To change the TabIndex property immediately while in the Designer, use the Show tab order interface (i.e. on the right-click menu).If you set the TabIndex property using the property page, the z-order is not updated until you save and exit the Window Designer.|
|UseVisualStyles||Set to TRUE to display this control in a Visual Style appearance (as if the XP manifest was active)|
|Column||Set this property to TRUE if you wish to allow the user to highlight a multi-column list box field by field (rather than one row at a time). This provides for spreadsheet grid style movement of the highlight bar. See Also: the COLUMN attribute.|
|DragID||To specify the type of Drag operations this control will generate, type up to 16 signatures, separated by commas. The DRAGID attribute specifies the LIST control can serve as a drag-and-drop host. DRAGID works in conjunction with the DROPID attribute.|
|DropID||To specify the type of Drag operations this control will accept, type up to 16 signatures, separated by commas. The Window Designer adds the DROPID attribute to the control, which indicates the control is a valid target for the drag and drop operations identified by the signatures.|
|Imm||To generate a message event each time the end user moves or resizes the selection bar, set Imm to TRUE. This adds the IMM attribute to the LIST. You are responsible for the code that executes upon notification of the event.|
|Mark||Optionally enables multiple item selection. Type in the label of a QUEUE field in the Mark field if you wish to allow the user to select more than one item from the list. The QUEUE field will flag the selected items.|
|VCR||Optionally provide VCR controls. Set VCR property to TRUE to provide VCR style controls for the list box. Optionally type the field equate label of an entry field to the right of the check box. When the user presses the Locator ( ? ) button, the focus shifts to that field. The user may type in data, then press TAB to scroll the list box to the closest matching entry.|
|Drop||Specifies whether this should be a regular or drop-down list box.|
|Count||Place a zero in the Count property for a normal list box. To create a drop-down list box, type the number of drop-down elements you wish to be visible.|
|Width||When the Drop field is non-zero, specify an integer constant here that sets the width of the dropped list, in dialog units.|
|Format||Specifies the print or display format of the data in the list control. Press the ellipsis button to call the Format Editor.|
|From||Fill the From field with the origin of the list data. Generally, this is the label of a QUEUE structure.|
|Justification||Specify left, center, right, decimal, or default justification. Default justification matches that specified in the data dictionary, if applicable. If you use decimal justification, you set the Offset to allow display of digits to the right of the decimal point.|
|Offset||Specify an indentation value for the list box item text, in dialog units.|
|Layout||Indicates the orientation of the LIST control. Left to Right maintains the original layout specified in the Window Designer. Right to Left essentially “flips” the controls' display as a mirror image of the layout specified in the Window Designer. Default field navigation moves from right to left. The setting in the Application Frame will cascade its setting to all child windows and controls that have the default setting active.|
|NoBar||Specifies the selection bar appears only when the list box has focus. See Also: the NOBAR attribute.|
|TextFont||Calls the Select Font dialog which lets you select the font (typeface), size, style (such as bold or italic), color, and font effects (underline and strikeout) for the selected control or window. As you choose options, the dialog box displays a sample of the selected font.|
|Use||This defines the USE attribute for the control. Place a variable or field equate label in the Use field. You may specify the variable which will receive the value that the user selects. Or, a field equate label to reference the list box in program statements.|
|Alert||Press the ellipsis to open a dialog that lets you add the ALRT attribute to a window or control. When the attribute is set, the window generates an EVENT:AlertKey if the user presses the key(s) you specify in this dialog, while the window has the focus.|
|Cursor||The Cursor field (the CURSOR attribute) lets you specify an alternate shape for the cursor when the user passes the cursor over the control. The drop-down list provides standard cursor choices such as I-Beam and Crosshair. To select an external cursor file (whose extension must be .CUR), choose Select File from the drop-down list, then pick the file using the standard file dialog.|
|Help ID||The Help ID field (the HLP attribute) takes a string constant specifying the key for accessing a specific topic in the Help document. This may be either a Help keyword or a context string.A Help keyword is a word or phrase indexed so that the user may search for it in the Help Search dialog. When you fill in the HLP attribute for a button, if the entry box has focus, when the user presses F1, the help file opens to the referenced topic. If more than one topic matches a keyword, the search dialog appears.When referencing a context string in the Help ID field, you must identify it with a leading tilde (~).|
|Key||Press the desired key or key combination (for example, CTRL+H). The keys you pressed will appear in the Key field, and will be supplied as parameters to the KEY or ALRT attribute for this control. The ESC, ENTER, and TAB keys cannot be specified by pressing them. For these keys, press the ellipsis (…) button and type “esc,” “enter,” or “tab.”|
|Message||The Message field (the MSG attribute) lets you specify text to display in the first zone of the status bar when the control has focus.|
|Tip||The TIP attribute on a control specifies the text to display in a “balloon help” box when the mouse cursor pauses over the control. Although there is no specific limit on the number of characters, the string should not be longer than can be displayed on the screen.|
|Disable||Disables or 'grays-out' the control when your program initially displays it. The Window Designer places the DISABLE attribute on the control. Use the ENABLE statement to allow the user access to the control.|
|Hide||Makes the control invisible at the time Windows would initially display it. Windows actually creates the control–it just doesn't display it on screen. The Window Designer places the HIDE attribute on the control. Use the UNHIDE statement to display the control.|
|Scroll||Specifies whether the control should move with the window when the user scrolls the window. By default (False) the control does not move with the window. Set the Scroll property to False to create a control that stays fixed when the user scrolls the window. The Window Designer places the SCROLL attribute on the control when checked.|
|Skip||Instructs the Window Designer to omit the control from the Tab Order. When the user TABS from field to field in the dialog box, Windows will not give the control focus. This is useful for seldom-used data fields. The Window Designer will place the SKIP attribute on the control.|
|Transparent||Specify whether you wish the control background to be Transparent. This instructs Windows to suppress the rectangular region around the text–the background. Normally, Windows will paint this the same uniform color as the window below the control. This adds the TRN attribute.|
|Flat||Set this property to True to give your list box a “flat” appearance (the list box control is on the same level as the window, and not recessed). Due to a built-in attribute to the runtime library, list boxes used in Drop List and Drop Combo controls are always flat and cannot be modified in the Formatter.|
Lets you set the location and size of the control.
The Position property lets you specify the AT attribute. Filling in the attribute manually is optional–you may also set the position and size visually by dragging with the mouse in the Window Designer.
To set the location of the control's Top Left Corner, set an X (horizontal) and Y (vertical) coordinate in Dialog units. The coordinate is relative to the top left corner of the structure containing it, that is, the window or the report band.
To set the control's size, choose from the following options for Width and Height.
|Default||The Clarion runtime library determines the size of the control based on the applicable font and picture token.|
|Full||The control is the full height or width of the window or report.|
|Fixed||Lets you set a precise width or height in Dialog units on a window, or in thousandths of inch, points, or millimeters on a report.|
|Horizontal||To add a horizontal scroll bar to your list box, set the Horizontal property to TRUE.|
|Vertical||To add a vertical scroll bar, set the Vertical property to TRUE.|
Scroll bars only appear when the list of items in the list is bigger than the window. These options add the HSCROLL, VSCROLL, and HVSCROLL attributes to the control.
|Embeds||Accesses the Embedded Source dialog for points surrounding the event handling for this control only.|