tk_getOpenFile(3tk) Tk Built-In Commands tk_getOpenFile(3tk)
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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 com-
mand 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 a non-existent file, the dialog box gives the user an error prompt and requires the user to give an alternative selection. 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 overwritten or not.
The following option-value pairs are possible as command line arguments to these two commands:
-confirmoverwrite boolean
Configures how the Save dialog reacts when the selected file already exists, and saving would overwrite it. A true value requests a
confirmation dialog be presented to the user. A false value requests that the overwrite take place without confirmation. Default
value is true.
-defaultextension extension
Specifies a string that will be appended to the filename if the user enters a filename without an extension. The default value is
the empty string, which means no extension will be appended to the filename in any case. This option is ignored on Mac OS X, which
does not require extensions to filenames, and the UNIX implementation guesses reasonable values for this from the -filetypes option
when this is not supplied.
-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 parameter is not specified, then the
files in the current working directory are displayed. If the parameter specifies a relative path, the return value will convert the
relative path to an absolute path.
-initialfile filename
Specifies a filename to be displayed in the dialog when it pops up.
-message string
Specifies a message to include in the client area of the dialog. This is only available on Mac OS X.
-multiple boolean
Allows the user to choose multiple files from the Open dialog.
-parent window
Makes window the logical parent of the file dialog. The file dialog is displayed on top of its parent window. On Mac OS X, this
turns the file dialog into a sheet attached to the 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.
-typevariable variableName
The global variable variableName is used to preselect which filter is used from filterList when the dialog box is opened and is
updated when the dialog box is closed, to the last selected filter. The variable is read once at the beginning to select the appro-
priate filter. If the variable does not exist, or its value does not match any filter typename, or is empty ({}), the dialog box
will revert to the default behavior of selecting the first filter in the list. If the dialog is canceled, the variable is not modi-
fied.
If the user selects a file, both tk_getOpenFile and tk_getSaveFile return the full pathname of this file. If the user cancels the opera-
tion, 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. exten-
sion 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 Macintosh 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. Usually, each file pattern corresponds to a distinct type of file. The use of more than one file pattern for one type of file is
only necessary on the Macintosh platform.
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 extension 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 least one of the extension(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 platform, extensions are
matched by the underlying operating 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 extension (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 ...
}
SEE ALSO
tk_chooseDirectory
KEYWORDS
file selection dialog
Tk 4.2 tk_getOpenFile(3tk)