"""
(C) 2014-2018 Roman Sirokov and contributors
Licensed under BSD license
http://github.com/r0x0r/pywebview/
"""
import sys
import json
import logging
import subprocess
import webbrowser
import ctypes
from threading import Event, Semaphore
import Foundation
import AppKit
import WebKit
from PyObjCTools import AppHelper
from objc import _objc, nil, super, pyobjc_unicode, registerMetaDataForSelector
from webview.localization import localization
from webview import OPEN_DIALOG, FOLDER_DIALOG, SAVE_DIALOG, parse_file_type, escape_string, _js_bridge_call
from webview.util import convert_string, parse_api_js, default_html
from .js.css import disable_text_select
# This lines allow to load non-HTTPS resources, like a local app as: http://127.0.0.1:5000
bundle = AppKit.NSBundle.mainBundle()
info = bundle.localizedInfoDictionary() or bundle.infoDictionary()
info['NSAppTransportSecurity'] = {'NSAllowsArbitraryLoads': Foundation.YES}
info['NSRequiresAquaSystemAppearance'] = Foundation.NO # Enable dark mode support for Mojave
# Dynamic library required by BrowserView.pyobjc_method_signature()
_objc_so = ctypes.cdll.LoadLibrary(_objc.__file__)
# Bridgesupport metadata for [WKWebView evaluateJavaScript:completionHandler:]
_eval_js_metadata = { 'arguments': { 3: { 'callable': { 'retval': { 'type': b'v' },
'arguments': { 0: { 'type': b'^v' }, 1: { 'type': b'@' }, 2: { 'type': b'@' }}}}}}
logger = logging.getLogger('pywebview')
logger.debug('Using Cocoa')
class BrowserView:
instances = {}
app = AppKit.NSApplication.sharedApplication()
cascade_loc = Foundation.NSMakePoint(100.0, 0.0)
class AppDelegate(AppKit.NSObject):
def applicationDidFinishLaunching_(self, notification):
i = list(BrowserView.instances.values())[0]
i.webview_ready.set()
class WindowDelegate(AppKit.NSObject):
def windowShouldClose_(self, window):
i = BrowserView.get_instance('window', window)
quit = localization['global.quit']
cancel = localization['global.cancel']
msg = localization['global.quitConfirmation']
if not i.confirm_quit or BrowserView.display_confirmation_dialog(quit, cancel, msg):
return Foundation.YES
else:
return Foundation.NO
def windowWillClose_(self, notification):
# Delete the closed instance from the dict
i = BrowserView.get_instance('window', notification.object())
del BrowserView.instances[i.uid]
if BrowserView.instances == {}:
BrowserView.app.stop_(self)
class JSBridge(AppKit.NSObject):
def initWithObject_(self, api_instance):
super(BrowserView.JSBridge, self).init()
self.api = api_instance
return self
def userContentController_didReceiveScriptMessage_(self, controller, message):
func_name, param = json.loads(message.body())
if param is WebKit.WebUndefined.undefined():
param = None
i = BrowserView.get_instance('js_bridge', self)
_js_bridge_call(i.uid, self.api, func_name, param)
class BrowserDelegate(AppKit.NSObject):
# Display a JavaScript alert panel containing the specified message
def webView_runJavaScriptAlertPanelWithMessage_initiatedByFrame_completionHandler_(self, webview, message, frame, handler):
AppKit.NSRunningApplication.currentApplication().activateWithOptions_(AppKit.NSApplicationActivateIgnoringOtherApps)
alert = AppKit.NSAlert.alloc().init()
alert.setInformativeText_(message)
alert.runModal()
if not handler.__block_signature__:
handler.__block_signature__ = BrowserView.pyobjc_method_signature(b'v@')
handler()
# Display a JavaScript confirm panel containing the specified message
def webView_runJavaScriptConfirmPanelWithMessage_initiatedByFrame_completionHandler_(self, webview, message, frame, handler):
ok = localization['global.ok']
cancel = localization['global.cancel']
if not handler.__block_signature__:
handler.__block_signature__ = BrowserView.pyobjc_method_signature(b'v@B')
if BrowserView.display_confirmation_dialog(ok, cancel, message):
handler(Foundation.YES)
else:
handler(Foundation.NO)
# Display an open panel for element
def webView_runOpenPanelWithParameters_initiatedByFrame_completionHandler_(self, webview, param, frame, handler):
i = list(BrowserView.instances.values())[0]
files = i.create_file_dialog(OPEN_DIALOG, '', param.allowsMultipleSelection(), '', [], main_thread=True)
if not handler.__block_signature__:
handler.__block_signature__ = BrowserView.pyobjc_method_signature(b'v@@')
if files:
urls = [Foundation.NSURL.URLWithString_(BrowserView.quote(i)) for i in files]
handler(urls)
else:
handler(nil)
# Open target="_blank" links in external browser
def webView_createWebViewWithConfiguration_forNavigationAction_windowFeatures_(self, webview, config, action, features):
if action.navigationType() == getattr(WebKit, 'WKNavigationTypeLinkActivated', 0):
webbrowser.open(action.request().URL().absoluteString(), 2, True)
return nil
# WKNavigationDelegate method, invoked when a navigation decision needs to be made
def webView_decidePolicyForNavigationAction_decisionHandler_(self, webview, action, handler):
# The event that might have triggered the navigation
event = AppKit.NSApp.currentEvent()
if not handler.__block_signature__:
handler.__block_signature__ = BrowserView.pyobjc_method_signature(b'v@i')
""" Disable back navigation on pressing the Delete key: """
# Check if the requested navigation action is Back/Forward
if action.navigationType() == getattr(WebKit, 'WKNavigationTypeBackForward', 2):
# Check if the event is a Delete key press (keyCode = 51)
if event and event.type() == AppKit.NSKeyDown and event.keyCode() == 51:
# If so, ignore the request and return
handler(getattr(WebKit, 'WKNavigationActionPolicyCancel', 0))
return
# Normal navigation, allow
handler(getattr(WebKit, 'WKNavigationActionPolicyAllow', 1))
# Show the webview when it finishes loading
def webView_didFinishNavigation_(self, webview, nav):
# Add the webview to the window if it's not yet the contentView
i = BrowserView.get_instance('webkit', webview)
if i:
if not webview.window():
i.window.setContentView_(webview)
i.window.makeFirstResponder_(webview)
if i.js_bridge:
script = parse_api_js(i.js_bridge.api)
i.webkit.evaluateJavaScript_completionHandler_(script, lambda a,b: None)
if not i.text_select:
i.webkit.evaluateJavaScript_completionHandler_(disable_text_select, lambda a,b: None)
print_hook = 'window.print = function() { window.webkit.messageHandlers.browserDelegate.postMessage("print") };'
i.webkit.evaluateJavaScript_completionHandler_(print_hook, lambda a,b: None)
i.loaded.set()
# Handle JavaScript window.print()
def userContentController_didReceiveScriptMessage_(self, controller, message):
if message.body() == 'print':
i = BrowserView.get_instance('_browserDelegate', self)
BrowserView.print_webview(i.webkit)
class FileFilterChooser(AppKit.NSPopUpButton):
def initWithFilter_(self, file_filter):
super(BrowserView.FileFilterChooser, self).init()
self.filter = file_filter
self.addItemsWithTitles_([i[0] for i in self.filter])
self.setAction_('onChange:')
self.setTarget_(self)
return self
def onChange_(self, sender):
option = sender.indexOfSelectedItem()
self.window().setAllowedFileTypes_(self.filter[option][1])
class WebKitHost(WebKit.WKWebView):
def mouseDown_(self, event):
if event.modifierFlags() & getattr(AppKit, 'NSEventModifierFlagControl', 1 << 18):
i = BrowserView.get_instance('webkit', self)
if i and not i.debug:
return
super(BrowserView.WebKitHost, self).mouseDown_(event)
def rightMouseDown_(self, event):
i = BrowserView.get_instance('webkit', self)
if i and i.debug:
super(BrowserView.WebKitHost, self).rightMouseDown_(event)
def performKeyEquivalent_(self, theEvent):
"""
Handle common hotkey shortcuts as copy/cut/paste/undo/select all/quit
:param theEvent:
:return:
"""
if theEvent.type() == AppKit.NSKeyDown and theEvent.modifierFlags() & AppKit.NSCommandKeyMask:
responder = self.window().firstResponder()
keyCode = theEvent.keyCode()
if responder != None:
handled = False
range_ = responder.selectedRange()
hasSelectedText = len(range_) > 0
if keyCode == 7 and hasSelectedText : #cut
responder.cut_(self)
handled = True
elif keyCode == 8 and hasSelectedText: #copy
responder.copy_(self)
handled = True
elif keyCode == 9: # paste
responder.paste_(self)
handled = True
elif keyCode == 0: # select all
responder.selectAll_(self)
handled = True
elif keyCode == 6: # undo
if responder.undoManager().canUndo():
responder.undoManager().undo()
handled = True
elif keyCode == 12: # quit
BrowserView.app.stop_(self)
return handled
def __init__(self, uid, title, url, width, height, resizable, fullscreen, min_size,
confirm_quit, background_color, debug, js_api, text_select, webview_ready):
BrowserView.instances[uid] = self
self.uid = uid
self.js_bridge = None
self._file_name = None
self._file_name_semaphore = Semaphore(0)
self._current_url_semaphore = Semaphore(0)
self.webview_ready = webview_ready
self.loaded = Event()
self.confirm_quit = confirm_quit
self.title = title
self.debug = debug
self.text_select = text_select
self.is_fullscreen = False
rect = AppKit.NSMakeRect(0.0, 0.0, width, height)
window_mask = AppKit.NSTitledWindowMask | AppKit.NSClosableWindowMask | AppKit.NSMiniaturizableWindowMask
if resizable:
window_mask = window_mask | AppKit.NSResizableWindowMask
# The allocated resources are retained because we would explicitly delete
# this instance when its window is closed
self.window = AppKit.NSWindow.alloc().\
initWithContentRect_styleMask_backing_defer_(rect, window_mask, AppKit.NSBackingStoreBuffered, False).retain()
self.window.setTitle_(title)
self.window.setBackgroundColor_(BrowserView.nscolor_from_hex(background_color))
self.window.setMinSize_(AppKit.NSSize(min_size[0], min_size[1]))
self.window.setAnimationBehavior_(AppKit.NSWindowAnimationBehaviorDocumentWindow)
BrowserView.cascade_loc = self.window.cascadeTopLeftFromPoint_(BrowserView.cascade_loc)
# Set the titlebar color (so that it does not change with the window color)
self.window.contentView().superview().subviews().lastObject().setBackgroundColor_(AppKit.NSColor.windowBackgroundColor())
self.webkit = BrowserView.WebKitHost.alloc().initWithFrame_(rect).retain()
self._browserDelegate = BrowserView.BrowserDelegate.alloc().init().retain()
self._windowDelegate = BrowserView.WindowDelegate.alloc().init().retain()
self._appDelegate = BrowserView.AppDelegate.alloc().init().retain()
self.webkit.setUIDelegate_(self._browserDelegate)
self.webkit.setNavigationDelegate_(self._browserDelegate)
self.window.setDelegate_(self._windowDelegate)
BrowserView.app.setDelegate_(self._appDelegate)
try:
self.webkit.evaluateJavaScript_completionHandler_('', lambda a, b: None)
except TypeError:
registerMetaDataForSelector(b'WKWebView', b'evaluateJavaScript:completionHandler:', _eval_js_metadata)
config = self.webkit.configuration()
config.userContentController().addScriptMessageHandler_name_(self._browserDelegate, 'browserDelegate')
try:
config.preferences().setValue_forKey_(Foundation.NO, 'backspaceKeyNavigationEnabled')
except:
pass
if self.debug:
config.preferences().setValue_forKey_(Foundation.YES, 'developerExtrasEnabled')
if js_api:
self.js_bridge = BrowserView.JSBridge.alloc().initWithObject_(js_api)
config.userContentController().addScriptMessageHandler_name_(self.js_bridge, 'jsBridge')
if url:
self.load_url(url)
else:
self.load_html(default_html, '')
if fullscreen:
self.toggle_fullscreen()
def show(self):
self.window.makeKeyAndOrderFront_(self.window)
if not BrowserView.app.isRunning():
# Add the default Cocoa application menu
self._add_app_menu()
self._add_view_menu()
BrowserView.app.activateIgnoringOtherApps_(Foundation.YES)
BrowserView.app.run()
else:
self.webview_ready.set()
def destroy(self):
AppHelper.callAfter(self.window.close)
def set_title(self, title):
def _set_title():
self.window.setTitle_(title)
AppHelper.callAfter(_set_title)
def toggle_fullscreen(self):
def toggle():
if self.is_fullscreen:
window_behaviour = 1 << 2 # NSWindowCollectionBehaviorManaged
else:
window_behaviour = 1 << 7 # NSWindowCollectionBehaviorFullScreenPrimary
self.window.setCollectionBehavior_(window_behaviour)
self.window.toggleFullScreen_(None)
AppHelper.callAfter(toggle)
self.is_fullscreen = not self.is_fullscreen
def set_window_size(self, width, height):
def _set_window_size():
frame = self.window.frame()
# Keep the top left of the window in the same place
frame.origin.y += frame.size.height
frame.origin.y -= height
frame.size.width = width
frame.size.height = height
self.window.setFrame_display_(frame, True)
AppHelper.callAfter(_set_window_size)
def get_current_url(self):
def get():
self._current_url = self.webkit.URL()
self._current_url_semaphore.release()
AppHelper.callAfter(get)
self._current_url_semaphore.acquire()
return self._current_url
def load_url(self, url):
def load(url):
page_url = Foundation.NSURL.URLWithString_(BrowserView.quote(url))
req = Foundation.NSURLRequest.requestWithURL_(page_url)
self.webkit.loadRequest_(req)
self.loaded.clear()
self.url = url
AppHelper.callAfter(load, url)
def load_html(self, content, base_uri):
def load(content, url):
url = Foundation.NSURL.URLWithString_(BrowserView.quote(url))
self.webkit.loadHTMLString_baseURL_(content, url)
self.loaded.clear()
AppHelper.callAfter(load, content, base_uri)
def evaluate_js(self, script):
def eval():
self.webkit.evaluateJavaScript_completionHandler_(script, handler)
def handler(result, error):
JSResult.result = None if result is None or result == 'null' else json.loads(result)
JSResult.result_semaphore.release()
class JSResult:
result = None
result_semaphore = Semaphore(0)
self.loaded.wait()
AppHelper.callAfter(eval)
JSResult.result_semaphore.acquire()
return JSResult.result
def create_file_dialog(self, dialog_type, directory, allow_multiple, save_filename, file_filter, main_thread=False):
def create_dialog(*args):
dialog_type = args[0]
if dialog_type == SAVE_DIALOG:
save_filename = args[2]
save_dlg = AppKit.NSSavePanel.savePanel()
save_dlg.setTitle_(localization["global.saveFile"])
if directory: # set initial directory
save_dlg.setDirectoryURL_(Foundation.NSURL.fileURLWithPath_(directory))
if save_filename: # set file name
save_dlg.setNameFieldStringValue_(save_filename)
if save_dlg.runModal() == AppKit.NSFileHandlingPanelOKButton:
file = save_dlg.filenames()
self._file_name = tuple(file)
else:
self._file_name = None
else:
allow_multiple = args[1]
open_dlg = AppKit.NSOpenPanel.openPanel()
# Enable the selection of files in the dialog.
open_dlg.setCanChooseFiles_(dialog_type != FOLDER_DIALOG)
# Enable the selection of directories in the dialog.
open_dlg.setCanChooseDirectories_(dialog_type == FOLDER_DIALOG)
# Enable / disable multiple selection
open_dlg.setAllowsMultipleSelection_(allow_multiple)
# Set allowed file extensions
if file_filter:
open_dlg.setAllowedFileTypes_(file_filter[0][1])
# Add a menu to choose between multiple file filters
if len(file_filter) > 1:
filter_chooser = BrowserView.FileFilterChooser.alloc().initWithFilter_(file_filter)
open_dlg.setAccessoryView_(filter_chooser)
open_dlg.setAccessoryViewDisclosed_(True)
if directory: # set initial directory
open_dlg.setDirectoryURL_(Foundation.NSURL.fileURLWithPath_(directory))
if open_dlg.runModal() == AppKit.NSFileHandlingPanelOKButton:
files = open_dlg.filenames()
self._file_name = tuple(files)
else:
self._file_name = None
if not main_thread:
self._file_name_semaphore.release()
if main_thread:
create_dialog(dialog_type, allow_multiple, save_filename)
else:
AppHelper.callAfter(create_dialog, dialog_type, allow_multiple, save_filename)
self._file_name_semaphore.acquire()
return self._file_name
def _add_app_menu(self):
"""
Create a default Cocoa menu that shows 'Services', 'Hide',
'Hide Others', 'Show All', and 'Quit'. Will append the application name
to some menu items if it's available.
"""
# Set the main menu for the application
mainMenu = AppKit.NSMenu.alloc().init()
self.app.setMainMenu_(mainMenu)
# Create an application menu and make it a submenu of the main menu
mainAppMenuItem = AppKit.NSMenuItem.alloc().init()
mainMenu.addItem_(mainAppMenuItem)
appMenu = AppKit.NSMenu.alloc().init()
mainAppMenuItem.setSubmenu_(appMenu)
appMenu.addItemWithTitle_action_keyEquivalent_(self._append_app_name(localization["cocoa.menu.about"]), "orderFrontStandardAboutPanel:", "")
appMenu.addItem_(AppKit.NSMenuItem.separatorItem())
# Set the 'Services' menu for the app and create an app menu item
appServicesMenu = AppKit.NSMenu.alloc().init()
self.app.setServicesMenu_(appServicesMenu)
servicesMenuItem = appMenu.addItemWithTitle_action_keyEquivalent_(localization["cocoa.menu.services"], nil, "")
servicesMenuItem.setSubmenu_(appServicesMenu)
appMenu.addItem_(AppKit.NSMenuItem.separatorItem())
# Append the 'Hide', 'Hide Others', and 'Show All' menu items
appMenu.addItemWithTitle_action_keyEquivalent_(self._append_app_name(localization["cocoa.menu.hide"]), "hide:", "h")
hideOthersMenuItem = appMenu.addItemWithTitle_action_keyEquivalent_(localization["cocoa.menu.hideOthers"], "hideOtherApplications:", "h")
hideOthersMenuItem.setKeyEquivalentModifierMask_(AppKit.NSAlternateKeyMask | AppKit.NSCommandKeyMask)
appMenu.addItemWithTitle_action_keyEquivalent_(localization["cocoa.menu.showAll"], "unhideAllApplications:", "")
appMenu.addItem_(AppKit.NSMenuItem.separatorItem())
# Append a 'Quit' menu item
appMenu.addItemWithTitle_action_keyEquivalent_(self._append_app_name(localization["cocoa.menu.quit"]), "terminate:", "q")
def _add_view_menu(self):
"""
Create a default View menu that shows 'Enter Full Screen'.
"""
mainMenu = self.app.mainMenu()
# Create an View menu and make it a submenu of the main menu
viewMenu = AppKit.NSMenu.alloc().init()
viewMenu.setTitle_(localization["cocoa.menu.view"])
viewMenuItem = AppKit.NSMenuItem.alloc().init()
viewMenuItem.setSubmenu_(viewMenu)
mainMenu.addItem_(viewMenuItem)
# TODO: localization of the Enter fullscreen string has no effect
fullScreenMenuItem = viewMenu.addItemWithTitle_action_keyEquivalent_(localization["cocoa.menu.fullscreen"], "toggleFullScreen:", "f")
fullScreenMenuItem.setKeyEquivalentModifierMask_(AppKit.NSControlKeyMask | AppKit.NSCommandKeyMask)
def _append_app_name(self, val):
"""
Append the application name to a string if it's available. If not, the
string is returned unchanged.
:param str val: The string to append to
:return: String with app name appended, or unchanged string
:rtype: str
"""
if "CFBundleName" in info:
val += " {}".format(info["CFBundleName"])
return val
@staticmethod
def nscolor_from_hex(hex_string):
"""
Convert given hex color to NSColor.
:hex_string: Hex code of the color as #RGB or #RRGGBB
"""
hex_string = hex_string[1:] # Remove leading hash
if len(hex_string) == 3:
hex_string = ''.join([c*2 for c in hex_string]) # 3-digit to 6-digit
hex_int = int(hex_string, 16)
rgb = (
(hex_int >> 16) & 0xff, # Red byte
(hex_int >> 8) & 0xff, # Blue byte
(hex_int) & 0xff # Green byte
)
rgb = [i / 255.0 for i in rgb] # Normalize to range(0.0, 1.0)
return AppKit.NSColor.colorWithSRGBRed_green_blue_alpha_(rgb[0], rgb[1], rgb[2], 1.0)
@staticmethod
def get_instance(attr, value):
"""
Return a BrowserView instance by the :value of its given :attribute,
and None if no match is found.
"""
for i in list(BrowserView.instances.values()):
try:
if getattr(i, attr) == value:
return i
except AttributeError:
break
return None
@staticmethod
def display_confirmation_dialog(first_button, second_button, message):
AppKit.NSApplication.sharedApplication()
AppKit.NSRunningApplication.currentApplication().activateWithOptions_(AppKit.NSApplicationActivateIgnoringOtherApps)
alert = AppKit.NSAlert.alloc().init()
alert.addButtonWithTitle_(first_button)
alert.addButtonWithTitle_(second_button)
alert.setMessageText_(message)
alert.setAlertStyle_(AppKit.NSWarningAlertStyle)
if alert.runModal() == AppKit.NSAlertFirstButtonReturn:
return True
else:
return False
@staticmethod
def print_webview(webview):
info = AppKit.NSPrintInfo.sharedPrintInfo().copy()
# default print settings used by Safari
info.setHorizontalPagination_(AppKit.NSFitPagination)
info.setHorizontallyCentered_(Foundation.NO)
info.setVerticallyCentered_(Foundation.NO)
imageableBounds = info.imageablePageBounds()
paperSize = info.paperSize()
if (Foundation.NSWidth(imageableBounds) > paperSize.width):
imageableBounds.origin.x = 0
imageableBounds.size.width = paperSize.width
if (Foundation.NSHeight(imageableBounds) > paperSize.height):
imageableBounds.origin.y = 0
imageableBounds.size.height = paperSize.height
info.setBottomMargin_(Foundation.NSMinY(imageableBounds))
info.setTopMargin_(paperSize.height - Foundation.NSMinY(imageableBounds) - Foundation.NSHeight(imageableBounds))
info.setLeftMargin_(Foundation.NSMinX(imageableBounds))
info.setRightMargin_(paperSize.width - Foundation.NSMinX(imageableBounds) - Foundation.NSWidth(imageableBounds))
# show the print panel
print_op = webview._printOperationWithPrintInfo_(info)
print_op.runOperationModalForWindow_delegate_didRunSelector_contextInfo_(webview.window(), nil, nil, nil)
@staticmethod
def pyobjc_method_signature(signature_str):
"""
Return a PyObjCMethodSignature object for given signature string.
:param signature_str: A byte string containing the type encoding for the method signature
:return: A method signature object, assignable to attributes like __block_signature__
:rtype:
"""
_objc_so.PyObjCMethodSignature_WithMetaData.restype = ctypes.py_object
return _objc_so.PyObjCMethodSignature_WithMetaData(ctypes.create_string_buffer(signature_str), None, False)
@staticmethod
def quote(string):
return string.replace(' ', '%20')
def create_window(uid, title, url, width, height, resizable, fullscreen, min_size,
confirm_quit, background_color, debug, js_api, text_select, webview_ready):
def create():
browser = BrowserView(uid, title, url, width, height, resizable, fullscreen, min_size,
confirm_quit, background_color, debug, js_api, text_select, webview_ready)
browser.show()
if uid == 'master':
create()
else:
AppHelper.callAfter(create)
def set_title(title, uid):
BrowserView.instances[uid].set_title(title)
def create_file_dialog(dialog_type, directory, allow_multiple, save_filename, file_types):
file_filter = []
# Parse file_types to obtain allowed file extensions
for s in file_types:
description, extensions = parse_file_type(s)
file_extensions = [i.lstrip('*.') for i in extensions.split(';') if i != '*.*']
file_filter.append([description, file_extensions or None])
i = list(BrowserView.instances.values())[0] # arbitary instance
return i.create_file_dialog(dialog_type, directory, allow_multiple, save_filename, file_filter)
def load_url(url, uid):
BrowserView.instances[uid].load_url(url)
def load_html(content, base_uri, uid):
BrowserView.instances[uid].load_html(content, base_uri)
def destroy_window(uid):
BrowserView.instances[uid].destroy()
def toggle_fullscreen(uid):
BrowserView.instances[uid].toggle_fullscreen()
def set_window_size(width, height, uid):
BrowserView.instances[uid].set_window_size(width, height)
def get_current_url(uid):
return BrowserView.instances[uid].get_current_url()
def evaluate_js(script, uid):
return BrowserView.instances[uid].evaluate_js(script)