tk_getOpenFile(n) Tk Built-In Commands 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
selection. If an application allows the user to create new files, it should do so by providing a sep-arate separate
arate 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:
-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 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. 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 application
default directory.
-initialfile filename
Specifies a filename to be displayed in the dialog when it pops up. This option is ignored on
the Macintosh platform.
-multiple
Allows the user to choose multiple files from the Open dialog. On the Macintosh, this is only
available when Navigation Services are installed.
-message string
Specifies a message to include in the client area of the dialog. This is only available on
the Macintosh, and only when Navigation Services are installed.
-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.
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 pat-tern pattern
tern 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 applica-tions applications
tions 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 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 extension AND belong
to the macType TEXT. To use the OR rule instead, you can use two file patterns, one with the exten-sions extensions
sions 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 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 platforms, 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(n)
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