A single line of text is visible, and a special control event is generated when the user presses Return or Enter (when the text field has the focus) and the event is not handled by the text field’s frame or dialog (see on-traverse-char in top-level-window<%> ).
Multiple lines of text are visible, and Enter is not handled specially.
Whenever the user changes the content of a text field, its callback procedure is invoked. A callback procedure is provided as an initialization argument when each text field is created.
The text field is implemented using a text% editor (with an inaccessible display). Thus, whereas text-field% provides only get-value and set-value to manipulate the text in a text field, the get-editor returns the field’s editor, which provides a vast collection of methods for more sophisticated operations on the text.
The keymap for the text field’s editor is initialized by calling the current keymap initializer procedure, which is determined by the current-text-keymap-initializer parameter.
(new text-field% [label label] [parent parent] [ [callback callback] [init-value init-value] [style style] [font font] [enabled enabled] [vert-margin vert-margin] [horiz-margin horiz-margin] [min-width min-width] [min-height min-height] [stretchable-width stretchable-width] [stretchable-height stretchable-height]]) → (is-a?/c text-field%) label : (or/c label-string? #f)
(or/c (is-a?/c frame%) (is-a?/c dialog%) (is-a?/c panel%) (is-a?/c pane%))
((is-a?/c text-field%) (is-a?/c control-event%) . -> . any) = (lambda (t e) (void)) init-value : string? = ""
(listof (or/c 'single 'multiple 'hscroll 'password 'vertical-label 'horizontal-label 'deleted)) = '(single) font : (is-a?/c font%) = normal-control-font enabled : any/c = #t vert-margin : (integer-in 0 1000) = 2 horiz-margin : (integer-in 0 1000) = 2 min-width : (integer-in 0 10000) = graphical-minimum-width min-height : (integer-in 0 10000) = graphical-minimum-height stretchable-width : any/c = #t stretchable-height : any/c = (memq 'multiple style)
If & occurs in label, it is specially parsed as for button%.
The callback procedure is called when the user changes the text in the text field or presses the Enter key (and Enter is not handled by the text field’s frame or dialog; see on-traverse-char in top-level-window<%>). If the user presses Enter, the type of event passed to the callback is 'text-field-enter, otherwise it is 'text-field.
If init-value is not "", the graphical minimum size for the text item is made wide enough to show init-value. Otherwise, a built-in default width is selected. For a text field in single-line mode, the graphical minimum size is set to show one line, and only the control’s width is stretchable by default. For a multiple-line text field, the graphical minimum size shows three lines of text, and it is stretchable in both directions by default.
The style must contain exactly one of 'single or 'multiple; the former specifies a single-line field and the latter specifies a multiple-line field. The 'hscroll style applies only to multiple-line fields; when 'hscroll is specified, the field has a horizontal scrollbar and autowrapping is disabled; otherwise, the field has no horizontal scrollbar and autowrapping is enabled. A multiple-line text field always has a vertical scrollbar. The 'password style indicates that the field should draw each character of its content using a generic symbol instead of the actual character. If style includes 'vertical-label, then the text field is created with a label above the control; if style does not include 'vertical-label (and optionally includes 'horizontal-label), then the label is created to the left of the text field. If style includes 'deleted, then the text field is created as hidden, and it does not affect its parent’s geometry; the text field can be made active later by calling parent’s add-child method..
The font argument determines the font for the control. For information about the enabled argument, see window<%>. For information about the horiz-margin and vert-margin arguments, see subarea<%>. For information about the min-width, min-height, stretchable-width, and stretchable-height arguments, see area<%>.