Merge pull request #106 from Davideddu/filechooser

Add file chooser facade and support for Linux and Windows

README.rst

@@ -32,4 +32,5 @@ Compass                            X             X             X
 Unique ID (IMEI or SN)             X             X             X   X       X   X
 Gyroscope                          X             X             X
 Battery                            X             X             X   X       X   X
+Native file chooser                                                X       X   X
 ================================== ============= ============= === ======= === =====

plyer/__init__.py

@@ -6,7 +6,7 @@
 
 __all__ = ('accelerometer', 'camera', 'gps', 'notification',
             'tts', 'email', 'vibrator', 'sms', 'compass',
-            'gyroscope', 'uniqueid', 'battery')
+            'gyroscope', 'uniqueid', 'battery', 'irblaster', 'filechooser')
 
 __version__ = '1.2.4-dev'
 
@@ -64,3 +64,7 @@
 #: IrBlaster proxy to :class:`plyer.facades.IrBlaster`
 irblaster = Proxy(
     'irblaster', facades.IrBlaster)
+
+#: FileChooser proxy to :class:`plyer.facades.FileChooser`
+filechooser = Proxy(
+    'filechooser', facades.FileChooser)

plyer/facades.py

@@ -8,7 +8,7 @@
 
 __all__ = ('Accelerometer', 'Camera', 'GPS', 'Notification',
            'TTS', 'Email', 'Vibrator', 'Sms', 'Compass',
-           'Gyroscope', 'UniqueID', 'Battery', 'IrBlaster')
+           'Gyroscope', 'UniqueID', 'Battery', 'IrBlaster', 'FileChooser')
 
 
 class Accelerometer(object):
@@ -501,3 +501,58 @@ def exists(self):
 
     def _exists(self):
         raise NotImplementedError()
+
+
+class FileChooser(object):
+    '''Native filechooser dialog facade.
+
+    open_file, save_file and choose_dir accept a number of arguments
+    listed below. They return either a list of paths (normally
+    absolute), or None if no file was selected or the operation was
+    canceled and no result is available.
+
+    Arguments:
+        * **path** *(string or None)*: a path that will be selected
+            by default, or None
+        * **multiple** *(bool)*: True if you want the dialog to
+            allow multiple file selection. (Note: Windows doesn't
+            support multiple directory selection)
+        * **filters** *(iterable)*: either a list of wildcard patterns
+            or of sequences that contain the name of the filter and any
+            number of wildcards that will be grouped under that name
+            (e.g. [["Music", "*mp3", "*ogg", "*aac"], "*jpg", "*py"])
+        * **preview** *(bool)*: True if you want the file chooser to
+            show a preview of the selected file, if supported by the
+            back-end.
+        * **title** *(string or None)*: The title of the file chooser
+            window, or None for the default title.
+        * **icon** *(string or None)*: Path to the icon of the file
+            chooser window (where supported), or None for the back-end's
+            default.
+        * **show_hidden** *(bool)*: Force showing hidden files (currently
+            supported only on Windows)
+
+    Important: these methods will return only after user interaction.
+    Use threads or you will stop the mainloop if your app has one.
+    '''
+
+    def _file_selection_dialog(self, **kwargs):
+        raise NotImplementedError()
+
+    def open_file(self, *args, **kwargs):
+        """Open the file chooser in "open" mode.
+        """
+        return self._file_selection_dialog(mode="open", *args, **kwargs)
+
+    def save_file(self, *args, **kwargs):
+        """Open the file chooser in "save" mode. Confirmation will be asked
+        when a file with the same name already exists.
+        """
+        return self._file_selection_dialog(mode="save", *args, **kwargs)
+
+    def choose_dir(self, *args, **kwargs):
+        """Open the directory chooser. Note that on Windows this is very
+        limited. Consider writing your own chooser if you target that
+        platform and are planning on using unsupported features.
+        """
+        return self._file_selection_dialog(mode="dir", *args, **kwargs)

plyer/platforms/linux/filechooser.py

@@ -0,0 +1,216 @@
+'''
+Linux file chooser
+------------------
+'''
+
+from plyer.facades import FileChooser
+from distutils.spawn import find_executable as which
+import os
+import subprocess as sp
+import time
+
+
+class SubprocessFileChooser(object):
+    """A file chooser implementation that allows using
+    subprocess back-ends.
+    Normally you only need to override _gen_cmdline, executable,
+    separator and successretcode.
+    """
+
+    executable = ""
+    """The name of the executable of the back-end.
+    """
+
+    separator = "|"
+    """The separator used by the back-end. Override this for automatic
+    splitting, or override _split_output.
+    """
+
+    successretcode = 0
+    """The return code which is returned when the user doesn't close the
+    dialog without choosing anything, or when the app doesn't crash.
+    """
+
+    path = None
+    multiple = False
+    filters = []
+    preview = False
+    title = None
+    icon = None
+    show_hidden = False
+
+    def __init__(self, **kwargs):
+        # Simulate Kivy's behavior
+        for i in kwargs:
+            setattr(self, i, kwargs[i])
+
+    _process = None
+
+    def _run_command(self, cmd):
+        self._process = sp.Popen(cmd, stdout=sp.PIPE)
+        while True:
+            ret = self._process.poll()
+            if ret != None:
+                if ret == self.successretcode:
+                    out = self._process.communicate()[0].strip()
+                    self.selection = self._split_output(out)
+                    return self.selection
+                else:
+                    return None
+            time.sleep(0.1)
+
+    def _split_output(self, out):
+        """This methods receives the output of the back-end and turns
+        it into a list of paths.
+        """
+        return out.split(self.separator)
+
+    def _gen_cmdline(self):
+        """Returns the command line of the back-end, based on the current
+        properties. You need to override this.
+        """
+        raise NotImplementedError()
+
+    def run(self):
+        return self._run_command(self._gen_cmdline())
+
+
+class ZenityFileChooser(SubprocessFileChooser):
+    """A FileChooser implementation using Zenity (on GNU/Linux).
+
+    Not implemented features:
+    * show_hidden
+    * preview
+    """
+
+    executable = "zenity"
+    separator = "|"
+    successretcode = 0
+
+    def _gen_cmdline(self):
+        cmdline = [which(self.executable), "--file-selection", "--confirm-overwrite"]
+        if self.multiple:
+            cmdline += ["--multiple"]
+        if self.mode == "save":
+            cmdline += ["--save"]
+        elif self.mode == "dir":
+            cmdline += ["--directory"]
+        if self.path:
+            cmdline += ["--filename", self.path]
+        if self.title:
+             cmdline += ["--name", self.title]
+        if self.icon:
+            cmdline += ["--window-icon", self.icon]
+        for f in self.filters:
+            if type(f) == str:
+                cmdline += ["--file-filter", f]
+            else:
+                cmdline += ["--file-filter", "{name} | {flt}".format(name=f[0], flt=" ".join(f[1:]))]
+        return cmdline
+
+class KDialogFileChooser(SubprocessFileChooser):
+    """A FileChooser implementation using KDialog (on GNU/Linux).
+
+    Not implemented features:
+    * show_hidden
+    * preview
+    """
+
+    executable = "kdialog"
+    separator = "\n"
+    successretcode = 0
+
+    def _gen_cmdline(self):
+        cmdline = [which(self.executable)]
+
+        filt = []
+
+        for f in self.filters:
+            if type(f) == str:
+                filt += [f]
+            else:
+                filt += list(f[1:])
+
+        if self.mode == "dir":
+            cmdline += ["--getexistingdirectory", (self.path if self.path else os.path.expanduser("~"))]
+        elif self.mode == "save":
+            cmdline += ["--getopenfilename", (self.path if self.path else os.path.expanduser("~")), " ".join(filt)]
+        else:
+            cmdline += ["--getopenfilename", (self.path if self.path else os.path.expanduser("~")), " ".join(filt)]
+        if self.multiple:
+            cmdline += ["--multiple", "--separate-output"]
+        if self.title:
+            cmdline += ["--title", self.title]
+        if self.icon:
+            cmdline += ["--icon", self.icon]
+        return cmdline
+
+class YADFileChooser(SubprocessFileChooser):
+    """A NativeFileChooser implementation using YAD (on GNU/Linux).
+
+    Not implemented features:
+    * show_hidden
+    """
+
+    executable = "yad"
+    separator = "|?|"
+    successretcode = 0
+
+    def _gen_cmdline(self):
+        cmdline = [which(self.executable), "--file-selection", "--confirm-overwrite", "--geometry", "800x600+150+150"]
+        if self.multiple:
+            cmdline += ["--multiple", "--separator", self.separator]
+        if self.mode == "save":
+            cmdline += ["--save"]
+        elif self.mode == "dir":
+            cmdline += ["--directory"]
+        if self.preview:
+            cmdline += ["--add-preview"]
+        if self.path:
+            cmdline += ["--filename", self.path]
+        if self.title:
+             cmdline += ["--name", self.title]
+        if self.icon:
+            cmdline += ["--window-icon", self.icon]
+        for f in self.filters:
+            if type(f) == str:
+                cmdline += ["--file-filter", f]
+            else:
+                cmdline += ["--file-filter", "{name} | {flt}".format(name=f[0], flt=" ".join(f[1:]))]
+        return cmdline
+
+CHOOSERS = {"gnome":     ZenityFileChooser,
+            "kde":       KDialogFileChooser,
+            "yad":       YADFileChooser}
+
+class LinuxFileChooser(FileChooser):
+    """FileChooser implementation for GNu/Linux. Accepts one additional
+    keyword argument, *desktop_override*, which, if set, overrides the
+    back-end that will be used. Set it to "gnome" for Zenity, to "kde"
+    for KDialog and to "yad" for YAD (Yet Another Dialog).
+    If set to None or not set, a default one will be picked based on
+    the running desktop environment and installed back-ends.
+    """
+
+    desktop = None
+    if str(os.environ.get("XDG_CURRENT_DESKTOP")).lower() == "kde" and which("kdialog"):
+        desktop = "kde"
+    elif which("yad"):
+        desktop = "yad"
+    elif which("zenity"):
+        desktop = "gnome"
+
+    def _file_selection_dialog(self, desktop_override=desktop, **kwargs):
+        if not desktop_override:
+            desktop_override = desktop
+        # This means we couldn't find any back-end
+        if not desktop_override:
+            raise OSError("No back-end available. Please install one.")
+
+        chooser = CHOOSERS[desktop_override]
+        c = chooser(**kwargs)
+        return c.run()
+
+
+def instance():
+    return LinuxFileChooser()