<?xml version="1.0" encoding="utf-8"?>
<page xmlns="http://projectmallard.org/1.0/" xmlns:its="http://www.w3.org/2005/11/its" xmlns:xi="http://www.w3.org/2001/XInclude" type="guide" style="task" id="filechooserdialog.py" xml:lang="pt-BR">
<info>
<title type="text">FileChooserDialog (Python)</title>
<link type="guide" xref="beginner.py#file-selectors"/>
<link type="seealso" xref="gmenu.py"/>
<link type="seealso" xref="toolbar_builder.py"/>
<link type="seealso" xref="textview.py"/>
<link type="next" xref="combobox.py"/>
<revision version="0.1" date="2012-08-14" status="draft"/>
<credit type="author copyright">
<name>Marta Maria Casetti</name>
<email its:translate="no">mmcasetti@gmail.com</email>
<years>2012</years>
</credit>
<desc>A dialog suitable for "Open" and "Save" commands</desc>
<mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
<mal:name>Rafael Ferreira</mal:name>
<mal:email>rafael.f.f1@gmail.com</mal:email>
<mal:years>2013</mal:years>
</mal:credit>
</info>
<title>FileChooserDialog</title>
<media type="image" mime="image/png" src="media/filechooserdialog_save.png"/>
<p>This FileChooserDialog saves a text document, which can be opened or written from scratch in a TextView (see below).</p>
<media type="image" mime="image/png" src="media/filechooserdialog_menu.png"/>
<p>It is also possible to call a FileChooserDialog to open a new document.</p>
<links type="sections"/>
<section id="overview">
<title>Steps to recreate the example</title>
<steps>
<item><p>Create a file .ui to describe an app-menu with items "New", "Open", "Save", "Save as", and "Quit". This can be done with Glade or in a text editor. See <link xref="#xml"/></p></item>
<item><p>Create a Python program for a Gtk.TextView with a Gtk.Buffer <code>self.buffer</code>, and a <code>self.file</code> which will be a Gio.File and we set initially as <code>None</code>.</p></item>
<item><p>In this program, create also the actions corresponding to the items in the app-menu, connect them to callback functions, and import the menu in the <code>do_startup()</code> method with a Gtk.Builder.</p></item>
<item><p>"New" and "Quit" actions and callback functions are quite straightforward, see <link xref="#code"/>. See <link xref="signals-callbacks.py"/> for a more detailed explanation of signals and callback functions.</p></item>
<item><p>"Open" callback should create and open a Gtk.FileChooserDialog for "Open", connected with another callback function for each of the two "Open" and "Cancel" buttons of the FileChooserDialog.</p></item>
<item><p>"Save as" works basically as "Open", but the callback function of the "Save" button depends on a more complex method <code>save_to_file()</code>.</p></item>
<item><p>"Save" can be reduced to the case where the file is <code>None</code>, that is the case where <code>self.file</code> is a new file, which in turn is the case "Save as"; and to the case where the file is not <code>None</code>, which in turn is reduced to <code>save_to_file()</code>.</p></item>
<item><p>Finally, the method <code>save_to_file()</code>: see <link xref="#code"/>, lines 146 - 175.</p></item>
</steps>
</section>
<section id="xml">
<title>XML file which creates the app-menu</title>
<code mime="application/xml" style="numbered"><?xml version="1.0"?>
<interface>
<menu id="appmenu">
<section>
<item>
<attribute name="label">New</attribute>
<attribute name="action">win.new</attribute>
</item>
<item>
<attribute name="label">Open</attribute>
<attribute name="action">win.open</attribute>
</item>
</section>
<section>
<item>
<attribute name="label">Save</attribute>
<attribute name="action">win.save</attribute>
</item>
<item>
<attribute name="label">Save As...</attribute>
<attribute name="action">win.save-as</attribute>
</item>
</section>
<section>
<item>
<attribute name="label">Quit</attribute>
<attribute name="action">app.quit</attribute>
</item>
</section>
</menu>
</interface>
</code>
</section>
<section id="code">
<title>Code used to generate this example</title>
<code mime="text/x-python" style="numbered">from gi.repository import Gtk
from gi.repository import Gdk
from gi.repository import Gio
from gi.repository import GObject
import sys
class MyWindow(Gtk.ApplicationWindow):
def __init__(self, app):
Gtk.Window.__init__(
self, title="FileChooserDialog Example", application=app)
self.set_default_size(400, 400)
# the actions for the window menu, connected to the callback functions
new_action = Gio.SimpleAction.new("new", None)
new_action.connect("activate", self.new_callback)
self.add_action(new_action)
open_action = Gio.SimpleAction.new("open", None)
open_action.connect("activate", self.open_callback)
self.add_action(open_action)
save_action = Gio.SimpleAction.new("save", None)
save_action.connect("activate", self.save_callback)
self.add_action(save_action)
save_as_action = Gio.SimpleAction.new("save-as", None)
save_as_action.connect("activate", self.save_as_callback)
self.add_action(save_as_action)
# the file
self.file = None
# the textview with the buffer
self.buffer = Gtk.TextBuffer()
textview = Gtk.TextView(buffer=self.buffer)
textview.set_wrap_mode(Gtk.WrapMode.WORD)
# a scrolled window for the textview
self.scrolled_window = Gtk.ScrolledWindow()
self.scrolled_window.set_policy(
Gtk.PolicyType.AUTOMATIC, Gtk.PolicyType.AUTOMATIC)
self.scrolled_window.add(textview)
self.scrolled_window.set_border_width(5)
# add the scrolled window to the window
self.add(self.scrolled_window)
# callback for new
def new_callback(self, action, parameter):
self.buffer.set_text("")
print("New file created")
# callback for open
def open_callback(self, action, parameter):
# create a filechooserdialog to open:
# the arguments are: title of the window, parent_window, action,
# (buttons, response)
open_dialog = Gtk.FileChooserDialog("Pick a file", self,
Gtk.FileChooserAction.OPEN,
(Gtk.STOCK_CANCEL, Gtk.ResponseType.CANCEL,
Gtk.STOCK_OPEN, Gtk.ResponseType.ACCEPT))
# not only local files can be selected in the file selector
open_dialog.set_local_only(False)
# dialog always on top of the textview window
open_dialog.set_modal(True)
# connect the dialog with the callback function open_response_cb()
open_dialog.connect("response", self.open_response_cb)
# show the dialog
open_dialog.show()
# callback function for the dialog open_dialog
def open_response_cb(self, dialog, response_id):
open_dialog = dialog
# if response is "ACCEPT" (the button "Open" has been clicked)
if response_id == Gtk.ResponseType.ACCEPT:
# self.file is the file that we get from the FileChooserDialog
self.file = open_dialog.get_file()
# an empty string (provisionally)
content = ""
try:
# load the content of the file into memory:
# success is a boolean depending on the success of the operation
# content is self-explanatory
# etags is an entity tag (can be used to quickly determine if the
# file has been modified from the version on the file system)
[success, content, etags] = self.file.load_contents(None)
except GObject.GError as e:
print("Error: " + e.message)
# set the content as the text into the buffer
self.buffer.set_text(content, len(content))
print("opened: " + open_dialog.get_filename())
# if response is "CANCEL" (the button "Cancel" has been clicked)
elif response_id == Gtk.ResponseType.CANCEL:
print("cancelled: FileChooserAction.OPEN")
# destroy the FileChooserDialog
dialog.destroy()
# callback function for save_as
def save_as_callback(self, action, parameter):
# create a filechooserdialog to save:
# the arguments are: title of the window, parent_window, action,
# (buttons, response)
save_dialog = Gtk.FileChooserDialog("Pick a file", self,
Gtk.FileChooserAction.SAVE,
(Gtk.STOCK_CANCEL, Gtk.ResponseType.CANCEL,
Gtk.STOCK_SAVE, Gtk.ResponseType.ACCEPT))
# the dialog will present a confirmation dialog if the user types a file name that
# already exists
save_dialog.set_do_overwrite_confirmation(True)
# dialog always on top of the textview window
save_dialog.set_modal(True)
# if self.file has already been saved
if self.file is not None:
try:
# set self.file as the current filename for the file chooser
save_dialog.set_file(self.file)
except GObject.GError as e:
print("Error: " + e.message)
# connect the dialog to the callback function save_response_cb()
save_dialog.connect("response", self.save_response_cb)
# show the dialog
save_dialog.show()
# callback function for the dialog save_dialog
def save_response_cb(self, dialog, response_id):
save_dialog = dialog
# if response is "ACCEPT" (the button "Save" has been clicked)
if response_id == Gtk.ResponseType.ACCEPT:
# self.file is the currently selected file
self.file = save_dialog.get_file()
# save to file (see below)
self.save_to_file()
# if response is "CANCEL" (the button "Cancel" has been clicked)
elif response_id == Gtk.ResponseType.CANCEL:
print("cancelled: FileChooserAction.SAVE")
# destroy the FileChooserDialog
dialog.destroy()
# callback function for save
def save_callback(self, action, parameter):
# if self.file is not already there
if self.file is not None:
self.save_to_file()
# self.file is a new file
else:
# use save_as
self.save_as_callback(action, parameter)
# save_to_file
def save_to_file(self):
# get the content of the buffer, without hidden characters
[start, end] = self.buffer.get_bounds()
current_contents = self.buffer.get_text(start, end, False)
# if there is some content
if current_contents != "":
# set the content as content of self.file.
# arguments: contents, etags, make_backup, flags, GError
try:
self.file.replace_contents(current_contents,
None,
False,
Gio.FileCreateFlags.NONE,
None)
print("saved: " + self.file.get_path())
except GObject.GError as e:
print("Error: " + e.message)
# if the contents are empty
else:
# create (if the file does not exist) or overwrite the file in readwrite mode.
# arguments: etags, make_backup, flags, GError
try:
self.file.replace_readwrite(None,
False,
Gio.FileCreateFlags.NONE,
None)
print("saved: " + self.file.get_path())
except GObject.GError as e:
print("Error: " + e.message)
class MyApplication(Gtk.Application):
def __init__(self):
Gtk.Application.__init__(self)
def do_activate(self):
win = MyWindow(self)
win.show_all()
def do_startup(self):
Gtk.Application.do_startup(self)
# app action quit, connected to the callback function
quit_action = Gio.SimpleAction.new("quit", None)
quit_action.connect("activate", self.quit_callback)
self.add_action(quit_action)
# get the menu from the ui file with a builder
builder = Gtk.Builder()
try:
builder.add_from_file("filechooserdialog.ui")
except:
print("file not found")
sys.exit()
menu = builder.get_object("appmenu")
self.set_app_menu(menu)
# callback function for quit
def quit_callback(self, action, parameter):
self.quit()
app = MyApplication()
exit_status = app.run(sys.argv)
sys.exit(exit_status)
</code>
</section>
<section id="methods">
<title>Useful methods for a FileChooserDialog</title>
<p>Note that the action of the FileChooserDialog can be one of the following: <code>Gtk.FileChooserAction.OPEN</code> (the file chooser will only let the user pick an existing file) <code>Gtk.FileChooserAction.SAVE</code> (the file chooser will let the user pick an existing file, or type in a new filename), <code>Gtk.FileChooserAction.SELECT_FOLDER</code> (the file chooser will let the user pick an existing folder), <code>Gtk.FileChooserAction.CREATE_FOLDER</code> (the file chooser will let the user name an existing or new folder).</p>
<p>Besides the methods used in the <link xref="#code"/>, we have:</p>
<list>
<item><p><code>set_show_hidden(True)</code> is used to display hidden files and folders.</p></item>
<item><p><code>set_select_multiple(True)</code> sets that multiple files can be selected. This is only relevant if the mode is <code>Gtk.FileChooserAction.OPEN</code> or <code>Gtk.FileChooserAction.SELECT_FOLDER</code>.</p></item>
<item><p>In a "Save as" dialog, <code>set_current_name(current_name)</code> sets <code>current_name</code> in the file selector, as if entered by the user; <code>current_name</code> can be something like <em>Untitled.txt</em>. This method should not be used except in a "Save as" dialog.</p></item>
<item><p>The default current folder is "recent items". To set another folder use <code>set_current_folder_uri(uri)</code>; but note you should use this method and cause the file chooser to show a specific folder only when you are doing a "Save as" command and you already have a file saved somewhere.</p></item>
</list>
</section>
<section id="references">
<title>API References</title>
<p>In this sample we used the following:</p>
<list>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkFileChooserDialog.html">GtkFileChooserDialog</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkFileChooser.html">GtkFileChooser</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkWindow.html">GtkWindow</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkTextView.html">GtkTextView</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkTextBuffer.html">GtkTextBuffer</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkScrolledWindow.html">GtkScrolledWindow</link></p></item>
<item><p><link href="http://developer.gnome.org/gio/stable/GFile.html">GFile</link></p></item>
<item><p><link href="http://developer.gnome.org/gio/stable/GSimpleAction.html">GSimpleAction</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkBuilder.html">GtkBuilder</link></p></item>
</list>
</section>
</page>