tk_getOpenFile(n)
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NAME
tk_getOpenFile, tk_getSaveFile - pop up a dialog box for
the user to select a file to open or save.
SYNOPSIS
tk_getOpenFile ?option value ...?
tk_getSaveFile ?option value ...?
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DESCRIPTION
The procedures tk_getOpenFile and tk_getSaveFile pop up a
dialog box for the user to select a file to open or save.
The tk_getOpenFile command is usually associated with the
Open command in the File menu. Its purpose is for the user
to select an existing file only. If the user enters an
non-existent file, the dialog box gives the user an error
prompt and requires the user to give an alternative selec-
tion. If an application allows the user to create new
files, it should do so by providing a separate New menu
command.
The tk_getSaveFile command is usually associated with the
Save as command in the File menu. If the user enters a
file that already exists, the dialog box prompts the user
for confirmation whether the existing file should be over-
written or not.
The following option-value pairs are possible as command
line arguments to these two commands:
-defaultextension extension
Specifies a string that will be appended to the
filename if the user enters a filename without an
extension. The defaut value is the empty string,
which means no extension will be appended to the
filename in any case. This option is ignored on the
Macintosh platform, which does not require exten-
sions to filenames.
-filetypes filePatternList
If a File types listbox exists in the file dialog
on the particular platform, this option gives the
filetypes in this listbox. When the user choose a
filetype in the listbox, only the files of that
type are listed. If this option is unspecified, or
if it is set to the empty list, or if the File
types listbox is not supported by the particular
platform then all files are listed regardless of
their types. See the section SPECIFYING FILE
PATTERNS below for a discussion on the contents of
filePatternList.
-initialdir directory
Specifies that the files in directory should be
displayed when the dialog pops up. If this parame-
ter is not specified, then the files in the current
working directory are displayed. This option may
not always work on the Macintosh. This is not a
bug. Rather, the General Controls control panel on
the Mac allows the end user to override the appli-
cation default directory.
-initialfile filename
Specifies a filename to be displayed in the dialog
when it pops up. This option is ignored by the
tk_getOpenFile command.
-parent window
Makes window the logical parent of the file dialog.
The file dialog is displayed on top of its parent
window.
-title titleString
Specifies a string to display as the title of the
dialog box. If this option is not specified, then a
default title is displayed. This option is ignored
on the Macintosh platform.
If the user selects a file, both tk_getOpenFile and
tk_getSaveFile return the full pathname of this file. If
the user cancels the operation, both commands return the
empty string.
SPECIFYING FILE PATTERNS
The filePatternList value given by the -filetypes option
is a list of file patterns. Each file pattern is a list of
the form
typeName {extension ?extension ...?} ?{macType ?macType ...?}?
typeName is the name of the file type described by this
file pattern and is the text string that appears in the
File types listbox. extension is a file extension for this
file pattern. macType is a four-character Macintosh file
type. The list of macTypes is optional and may be omitted
for applications that do not need to execute on the Macin-
tosh platform.
Several file patterns may have the same typeName, in which
case they refer to the same file type and share the same
entry in the listbox. When the user selects an entry in
the listbox, all the files that match at least one of the
file patterns corresponding to that entry are listed. Usu-
ally, each file pattern corresponds to a distinct type of
file. The use of more than one file patterns for one type
of file is necessary on the Macintosh platform only.
On the Macintosh platform, a file matches a file pattern
if its name matches at least one of the extension(s) AND
it belongs to at least one of the macType(s) of the file
pattern. For example, the C Source Files file pattern in
the sample code matches with files that have a .c exten-
sion AND belong to the macType TEXT. To use the OR rule
instead, you can use two file patterns, one with the
extensions only and the other with the macType only. The
GIF Files file type in the sample code matches files that
EITHER have a .gif extension OR belong to the macType
GIFF.
On the Unix and Windows platforms, a file matches a file
pattern if its name matches at at least one of the exten-
sion(s) of the file pattern. The macTypes are ignored.
SPECIFYING EXTENSIONS
On the Unix and Macintosh platforms, extensions are
matched using glob-style pattern matching. On the Windows
platforms, extensions are matched by the underlying oper-
ating system. The types of possible extensions are: (1)
the special extension * matches any file; (2) the special
extension "" matches any files that do not have an exten-
sion (i.e., the filename contains no full stop character);
(3) any character string that does not contain any wild
card characters (* and ?).
Due to the different pattern matching rules on the various
platforms, to ensure portability, wild card characters are
not allowed in the extensions, except as in the special
extension *. Extensions without a full stop character
(e.g, ~) are allowed but may not work on all platforms.
EXAMPLE
set types {
{{Text Files} {.txt} }
{{TCL Scripts} {.tcl} }
{{C Source Files} {.c} TEXT}
{{GIF Files} {.gif} }
{{GIF Files} {} GIFF}
{{All Files} * }
}
set filename [tk_getOpenFile -filetypes $types]
if {$filename != ""} {
# Open the file ...
}
KEYWORDS
file selection dialog