NAME¶
Tk::getOpenFile, Tk::getSaveFile - pop up a dialog box for the user to select a
file to open or save.
SYNOPSIS¶
$widget->
getOpenFile(?
-option=>value, ...>?)
$widget->
getSaveFile(?
-option=>value, ...>?)
DESCRIPTION¶
The methods
getOpenFile and
getSaveFile pop up a dialog box for
the user to select a file to open or save.
The
getOpenFile method 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 separate
New menu command.
The
getSaveFile method 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.
If the user selects a file, both
getOpenFile and
getSaveFile
return the full pathname of this file. If the user cancels the operation, both
commands return an undefined value.
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 default 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 => [filePattern ?, ...?]
- 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
"SPECIFYING FILE PATTERNS" below for a discussion on the
contents of filePatterns.
- -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. 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 by the getOpenFile method.
- -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.
- -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.
SPECIFYING FILE PATTERNS¶
The
filePatterns given by the
-filetypes option are 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
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
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
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.
CAVEATS¶
See "CAVEATS" in Tk::chooseDirectory.
EXAMPLE¶
my $types = [
['Text Files', ['.txt', '.text']],
['TCL Scripts', '.tcl' ],
['C Source Files', '.c', 'TEXT'],
['GIF Files', '.gif', ],
['GIF Files', '', 'GIFF'],
['All Files', '*', ],
];
my $filename = $widget->getOpenFile(-filetypes=>$types);
if ($filename ne "") {
# Open the file ...
}
SEE ALSO¶
Tk::FBox, Tk::FileSelect
KEYWORDS¶
file selection dialog