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I typically package up my python projects as .zip files so it's easy for other people to execute them. (See http://www.python.org/dev/peps/pep-0441/ )

It appears as though the "with enaml.imports()" feature does not support this at present. It would be a useful thing to add.

The default left close button on dock tabs should be hidden on OSX.

In some applications it is important to intercept a window before it is closed. (Canonical example: put up a message box saying "You have unsaved data. Are you sure you want to quit?", if the answer is yes, then continue; if the answer is no then don't close the window.

Pressing a window's close box appears to do this sequence:

• hide window
• emit closed event
• destroy the window's resources

Something should go ahead of this sequence to allow a window to intercept a closing event and prevent further actions if appropriate.

https://github.com/nucleic/enaml/blob/master/enaml/widgets/window.py

def _handle_close(self):
      """ Handle the close event from the proxy widget.

      """
      self.visible = False
      self.closed()
      if self.destroy_on_close:
          deferred_call(self.destroy)

I managed to trick traitsui into using high-dpi settings and observe that enaml does not take high-dpi (retina) screens into account.
I know its debatable whether to what extent enaml should take care of providing these settings, so curious to have your view on this.

http://blog.qt.digia.com/blog/2013/04/25/retina-display-support-for-mac-os-ios-and-x11/

In PySide, QFileDialog does not have the method getOpenFileNameAndFilter.

To see the problem, run the 'file_dialog.enaml' example (in examples/widgets), and click on the Browse button. Here's the traceback that I get:

$ enaml-run file_dialog.enaml 
Traceback (most recent call last):
  File "/home/warren/local_anaconda_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/qt/q_deferred_caller.py", line 38, in _onPosted
    callback()
  File "/home/warren/local_anaconda_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/qt/q_deferred_caller.py", line 56, in <lambda>
    f = lambda: callback(*args, **kwargs)
  File "/home/warren/local_anaconda_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/qt/qt_file_dialog.py", line 30, in exec_dialog
    path, selected_filter = QFileDialog.getOpenFileNameAndFilter(
AttributeError: type object 'PySide.QtGui.QFileDialog' has no attribute 'getOpenFileNameAndFilter'

Note: I built enaml using the changes in #53 and #54. Without them, other errors will occur before this one.

Are there plans in the works to support table view/model objects?

I've got more of a Java background than Python; the JTable class worked very nicely for me with its ability to act as a view for a separate table model, using the GlazedLists library. At this point I'm not sure what I should use to put a table together using enaml.

platform: Anaconda 1.8.0, enaml 0.8.9 on Windows 7, 64-bit

As discussed in the google group, I have a simple example where the order of events is as follows:

1. Push button sets P1 equal to !P2. (event is fired)
2. Observer of P1 does these steps on changes to P1:
   1. some task (which may take zero time; here in my example it is the pathological case of zero time)
   2. then sets P2 = P1. (event is fired)

Separately: Enaml view observes P1 and P2 sets push button enable state to P1 == P2. (So it should be disabled for a very short time during step 2i, then re-enabled.)

I have added a generic observer on both P1 and P2 which prints out the entire change event in each case. The bug appears to be that the enamldef subscription operator only sees one event, even though there are two events.

Test files here: https://gist.github.com/jason-s/a66731b44cf042c8e6ca revision 2

When I run it one way, I get these results (my comments in [[ ]] ), which gives the external result I expect. (Testcase "A")

>python buttontest2.py
Event occurred: {'object': <__main__.P1P2Model object at 0x0000000004751888>, 'type': 'create', 'name': 'p1', 'value': False}
Event occurred: {'object': <__main__.P1P2Model object at 0x0000000004751888>, 'type': 'create', 'name': 'p2', 'value': False}
P1Observer sees p1 = False, sets p2 from False -> False
enamlview Main sees a change: p1=False p2=False
[[jms: click "go" button]]
Event occurred: {'value': True, 'object': <__main__.P1P2Model object at 0x0000000004751888>, 'type': 'update', 'name': 'p1', 'oldvalue': False}
P1Observer sees p1 = True, sets p2 from False -> True
Event occurred: {'value': True, 'object': <__main__.P1P2Model object at 0x0000000004751888>, 'type': 'update', 'name': 'p2', 'oldvalue': False}
enamlview Main sees a change: p1=True p2=True
[[jms: click "stop" button]]
Event occurred: {'value': False, 'object': <__main__.P1P2Model object at 0x0000000004751888>, 'type': 'update', 'name': 'p1', 'oldvalue': True}
P1Observer sees p1 = False, sets p2 from True -> False
Event occurred: {'value': False, 'object': <__main__.P1P2Model object at 0x0000000004751888>, 'type': 'update', 'name': 'p2', 'oldvalue': True}
enamlview Main sees a change: p1=False p2=False

But when I change the order of adding observers (this happens at the start of program), I get this: (Testcase "B")

>python buttontest2.py viewfirst
Event occurred: {'object': <__main__.P1P2Model object at 0x000000000485C508>, 'type': 'create', 'name': 'p1', 'value': False}
Event occurred: {'object': <__main__.P1P2Model object at 0x000000000485C508>, 'type': 'create', 'name': 'p2', 'value': False}
enamlview Main sees a change: p1=False p2=False
[[jms: click "go" button]]
Event occurred: {'value': True, 'object': <__main__.P1P2Model object at 0x000000000485C508>, 'type': 'update', 'name': 'p1', 'oldvalue': False}
enamlview Main sees a change: p1=True p2=False
P1Observer sees p1 = True, sets p2 from False -> True
Event occurred: {'value': True, 'object': <__main__.P1P2Model object at 0x000000000485C508>, 'type': 'update', 'name': 'p2', 'oldvalue': False}
[[jms: go button stays disabled]]

The general observer always shows 2 events (the first event for the change in p1, the second event for the change in p2), but the subscription operator calls bequal() only once, whether in test case A or test case B. I expect it to be called twice, once per event.

What's going on here? Is there an implicit thread issue that I don't know about? I'm not explicitly creating any threads.

Code pasted inline breaks currently.

from enaml.widgets.api import Window, Container, PushButton

enamldef Content(Container):
""" The primary application content.

This 'button_foreground' alias provides access to the internal
push button's foreground color.

"""
alias button_bar: button.bar
PushButton: button:
    attr bar = 1

enamldef Main(Window):
""" The main application window.

This window uses the 'button_foreground' alias of the central
content to bind to its internal push button's foreground color.

"""
title = 'Simple Attribute Alias'
Content: pass

Make Stacks and Notebooks return size hints based on their currently visible item and not the maximum of all the items contained within them.

I'm not sure if this is an enaml question or a PySide question, but I want to handle close events on my main window, so I can either trigger a cleanup action, and/or prevent the window from being closed (e.g. the "You have unsaved data -- are you sure you want to quit?" kind of situation)

How can I do this? I'm using enaml.qt.qt_application.QtApplication along with a main window that is enamldef'd from enaml.widgets.api.Window.

Do you have an example of enaml code to set a window icon when it is minimized?

The window code https://github.com/nucleic/enaml/blob/master/enaml/widgets/window.py
looks like it supports an icon, but I'm not sure how to declare it in enaml.

I am in the process of adding native support for editing enaml files in the Spyder IDE. It is working great so far, I have syntax highlighting and support for introspection. Jedi is used to pick up python-like completions, goto definition, and docs. A regex-based method is used for completions and goto when Jedi fails (for more enaml-specific things). Note that pressing Tab will also trigger a completion (not yet a feature in the mainline Spyder).

Two questions:

• Do you have any suggests for improvement or any other features you'd like to see?
• What should I use as an icon when editing enaml files?

Spyder uses Mercurial and Google Code, so you can find my repo as follows:

hg clone https://[email protected]/p/spyderlib-jedi/ 
hg bookmark extras
cd <spyderlib>
./bootstrap.py

The enaml-specific changes I made were:

• augmented: spyderlib.spyderlib.widgets.sourcecode.codeeditor.CodeEditor
• added: spyderlib.spyderlib.widgets.sourcecode.syntaxhighlighter.EnamlSH

You will need jedi >= 0.7.0 for the Jedi features. (pip install jedi).

When a button triggers a long running task no UI updates happen until the handler runs its course. What is the correct way to accomplish the following behavior?

        PushButton: step:
            text = 'Step'
            clicked ::
                step.enabled = False
                worker.step()
                step.enabled = True

Tried wrapping in various combinations of Application.deferred_call()/schedule() to no avail.

The documentation at http://nucleic.github.io/enaml/docs/index.html starts out extremely well in the "Getting Started" section, but then suddenly stops. For example, the following sections are missing from the docs pages:

• Data Models
• Constraints Layout
• Architecture Reference
• FAQ
• Examples (critical!)

This is disconcerting for new users approaching the framework and it's not obvious that the in-repo examples are complete and functional. For example, the Examples page could simply link to the source view of the Examples directory: https://github.com/nucleic/enaml/tree/master/examples

Creating documentation can be an arduous process, but it's very important to the long-term viability of any framework. Please consider adding the missing documentation, or at the very least link to 0.6.x documentation with appropriate notes explaining key differences in newer versions, perhaps by linking to the changelog: https://github.com/nucleic/enaml/blob/master/releasenotes.rst

It would be useful to have manual access to the _refresh_mpl_widget() method in https://github.com/nucleic/enaml/blob/master/enaml/qt/qt_mpl_canvas.py but from the https://github.com/nucleic/enaml/blob/master/enaml/widgets/mpl_canvas.py and user python side of things. This would allow refresh to be called when a Figure is updated, to save on the overhead of creating a new Figure every time a refresh is desired.

You can get a segfault reliably by running examples/widgets/tool_bar.enaml, selecting one of the exclusive toolbar buttons and then closing the window.

Looking at the stack trace, it would appear that the toolbar destructor is attempting to reference a Python object which has already been garbage collected.

This may be a PySide issue.

http://nucleic.github.io/enaml/docs/examples/ex_popup_view.html

I just tried it -- really slick-looking UI, but it crashes if I click on the main window when any of the popups are open.

Here's the traceback. I'm using Anaconda Python 1.8.0 (ignore the "1.6.0" directory path) which includes enaml 0.8.3, pyside 1.2.1. PC platform = Windows 7, 64-bit.

If this has been fixed since then, let me know + I'll ping the Anaconda people.

Traceback (most recent call last):
  File "c:\app\python\anaconda\1.6.0\lib\site-packages\enaml\qt\qt_popup_view.py", line 113, in on_closed
    d._popup_closed()
  File "c:\app\python\anaconda\1.6.0\lib\site-packages\enaml\widgets\popup_view.py", line 253, in _popup_closed
    deferred_call(self.destroy)
  File "c:\app\python\anaconda\1.6.0\lib\site-packages\enaml\application.py", line 462, in deferred_call
    app.deferred_call(callback, *args, **kwargs)
  File "c:\app\python\anaconda\1.6.0\lib\site-packages\enaml\qt\qt_application.py", line 72, in deferred_call
    deferredCall(callback, *args, **kwargs)
  File "c:\app\python\anaconda\1.6.0\lib\site-packages\enaml\qt\q_deferred_caller.py", line 61, in deferredCall
    event = DeferredCallEvent(callback, args, kwargs)
  File "c:\app\python\anaconda\1.6.0\lib\site-packages\enaml\qt\q_deferred_caller.py", line 21, in __init__
    super(DeferredCallEvent, self).__init__(self.Type)
TypeError: 'PySide.QtCore.QEvent' called with wrong argument types:
  PySide.QtCore.QEvent(int)
Supported signatures:
  PySide.QtCore.QEvent(PySide.QtCore.QEvent.Type)

any plans to make it Python 3 compatible?

I guess opening an issue for this kind of underscores the point - has nucleic enaml got a mailing list / forum? Traditionally, enthought's devel list was the place to consult the enaml developers, but this situation has become somewhat confusing. Given that enthought is often fwd'ing to enaml on the mailing list, perhaps it time to consider this?

Looking fwd not having to polute this namespace no more ;)

When changing between styles on the DockArea the labels on the dock item title bars elide their text if the font size incurs a large increase. This is likely caused by QTextLabel caching it's size hint and not invalidating that cache on a style change. An appropriate fix would be to catch the QEvent::StyleChange and invalidate the cached hint.

With enaml 0.8.0 (2b2dfd6) and atom 0.3.3 (6dcf3e411bfc7ebb2ee8faffa7c1a0d5ab85b99b), and using the version of PySide in the latest anaconda, many of the examples raise a RuntimeError. E.g.

$ enaml-run form.enaml 
Traceback (most recent call last):
  File "/home/warren/local_enaml/bin/enaml-run", line 9, in <module>
    load_entry_point('enaml==0.8.0', 'console_scripts', 'enaml-run')()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/runner.py", line 64, in main
    window.show()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/widgets/window.py", line 331, in show
    self.activate_proxy()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/widgets/toolkit_object.py", line 206, in activate_proxy
    child.activate_proxy()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/widgets/toolkit_object.py", line 206, in activate_proxy
    child.activate_proxy()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/widgets/toolkit_object.py", line 203, in activate_proxy
    self.activate_top_down()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/widgets/toolkit_object.py", line 219, in activate_top_down
    self.proxy.activate_top_down()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/qt/qt_toolkit_object.py", line 68, in activate_top_down
    self.init_widget()
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/qt/qt_field.py", line 78, in init_widget
    self.set_submit_triggers(d.submit_triggers)
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/qt/qt_field.py", line 168, in set_submit_triggers
    widget.lostFocus.disconnect(handler)
RuntimeError: Failed to disconnect signal lostFocus().

is there any way you could put a quick doc about the object model / Widget API? I've looked at the source but I can't figure out where it gets various parts of its functionality.

I need to figure out how to add PySide GUI components that are not currently covered by enaml; it appears as though the widgets added in the .enaml file have to be descended from the Declarative class. So I wanted to try to add additional widgets outside of the .enaml file. All I can figure out so far is that the .children attribute allows accessing child elements from a parent.

Is there an equivalent to the DOM getElementById()? I want to create a dummy container in the .enaml file and then manually add a child element into it from my .py file.

Running the examples/widgets/flow_area.enaml file gives this traceback.

Traceback (most recent call last):
  File "/Users/cwebster/Library/Enthought/Canopy_64bit/User/bin/enaml-run", line 9, in <module>
    load_entry_point('enaml==0.7.16', 'console_scripts', 'enaml-run')()
  File "/Users/cwebster/src/enaml/enaml/runner.py", line 57, in main
    exec code in ns
  File "flow_area.enaml", line 89, in 
    enamldef Item(FlowItem):
  File "/Users/cwebster/src/enaml/enaml/core/compiler_helpers.py", line 36, in __make_enamldef_helper
    Resolver.resolve(node, f_globals)
  File "/Users/cwebster/src/enaml/enaml/core/resolver.py", line 55, in resolve
    resolver._call_operators()
  File "/Users/cwebster/src/enaml/enaml/core/resolver.py", line 233, in _call_operators
    binding.operator_func(klass, binding)
  File "/Users/cwebster/src/enaml/enaml/core/operators.py", line 489, in op_simple
    bind_write_operator(klass, binding, OpSimple(binding))
  File "/Users/cwebster/src/enaml/enaml/core/operators.py", line 463, in bind_write_operator
    clone = member.clone()
  File "/Users/cwebster/src/atom/atom/list.py", line 76, in clone
    clone.set_validate_mode(mode, item_clone)
TypeError: Expected object of type `Validate`. Got object of type `int` instead.

You get similar errors with group_box.enaml, main_window.enaml, mpl_canvas.enaml, and popup_view.enaml.

Also happens in examples/stdlib/mapped_view.enaml, examples/dynamic/fields.enaml and examples/layout/advances/button_ring.enaml.

This is running under PySide, so it could be a difference between PyQt and PySide validation systems.

This compiles and runs but shouldn't: can't have keyword arg after non-keyword arg.

enamldef Main(Window):
    Container:
        constraints = [vbox(spacer=12, hbox(foo, bar), spacer=12)]
        PushButton: foo: pass
        PushButton: bar: pass

as it says on the tin

as it says on the tin

The tool bar items in a DockArea do not render the drop shadow on PySide. My hunch is that the ownership of the QGraphicsDropShadowEffect is not transferred properly in the call to QWidget::setGraphicsEffect.

A similar bug has already been filed:
https://bugreports.qt-project.org/browse/PYSIDE-66

Hopefully the pyside community can do something about this...

The compiler generates bad code for this:

from enaml.widgets.api import *


template Foo():
    Field:
        placeholder = 'foo'

enamldef Main(Window):
    Container:
        Foo(): f:
            f.text = f.placeholder

The scope key for the outer closure scope is not correctly passed to compiler helper which binds the expression for f.placeholder.

When I run the tutorial example "hello_world.py" using enaml 0.7.19 packaged with anaconda, it works fine. When I install enaml from the master branch (e.g. 2b2dfd6) at nucleic/enaml, I get this:

$ python hello_world.py 
Traceback (most recent call last):
  File "hello_world.py", line 25, in <module>
    main()
  File "hello_world.py", line 14, in main
    from hello_world_view import Main
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/core/import_hooks.py", line 143, in load_module
    exec code in mod.__dict__
  File "/home/warren/gitwork/nucleic_enaml/examples/tutorial/hello_world/hello_world_view.enaml", line 1, in 
    #------------------------------------------------------------------------------
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/core/compiler_helpers.py", line 15, in <module>
    from .declarative import Declarative, d_
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/core/declarative.py", line 54, in <module>
    class Declarative(Object):
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/core/declarative_meta.py", line 123, in __new__
    patch_d_member(value)
  File "/home/warren/local_enaml/lib/python2.7/site-packages/enaml-0.8.0-py2.7-linux-x86_64.egg/enaml/core/declarative_meta.py", line 90, in patch_d_member
    member.add_static_observer(declarative_change_handler)
TypeError: Error when calling the metaclass bases
    Expected object of type `str`. Got object of type `function` instead.

I get the same error when running the widgets examples.

In trying to run the message_box example, if I click on any of the buttons I get the error message: AttributeError: 'NoneType' object has no attribute 'setWidget'. The call stack shows that this happens in the call to set_parent.

Possibly relevant: I am using PySide rather than PyQt.

Looks like the live editor won't handle the import statements.
I ran into this issue both on enaml 0.8.4 and 0.8.8

If I simply try to import an .enaml file that does not have a trailing blank line, I get the error OverflowError: unsigned byte integer is less than minimum at line 720 in byteplay.py's to_code method.

The documentation at http://nucleic.github.io/enaml/docs/index.html starts out extremely well in the "Getting Started" section, but then suddenly stops. For example, the following sections are missing entirely:

• Data Models
• Constraints Layout
• Architecture Reference
• FAQ
• Examples (critical!)

Creating documentation can be an arduous process, but it's very important to the long-term viability of any framework. Please consider adding the missing documentation, or at the very least link to 0.6.x documentation with appropriate notes explaining key differences in newer versions.

The following enaml file:

from atom.api import Atom, Float, Typed

from enaml.widgets.api import MainWindow, Container, Form
from enaml.stdlib.fields import FloatField

class Quote(Atom):
    price = Float()

class Model(Atom):
    quote = Typed(Quote)

enamldef Main(MainWindow):
    attr model = Model()

    Container:
        Form:
            FloatField:
                value := model.quote.price

causes a NameError: name 'value' is not defined exception. The issue is that the quote attribute defaults to None
and the price attribute can't be bound.

Is the dependency on SIP creating a dependency on PyQT (and messing up support of PySide?) I'm getting ImportErrors from not having sip installed when testing the hello_world example.

PS - this is with version 0.7.6, as distributed with Anaconda 1.6.1 for Windows, x64

OK, I've figured out how to make custom widgets (without using RawWidget as in #70 ), but I cannot figure out how to get them to play nicely with enaml's size constraints, or how the enaml widgets do it.

Here's what I'm using. The TableView gets instantiated properly, but never changes its size even if I resize my main enaml window. If I include the TableView in horizontal and vertical constraints, it still stays at fixed size and prevents all the other widgets with layout constraints from being automatically resized when my main window is resized. (If I don't include the TableView in horizontal constraints, the other widgets get resized properly.)

I've tried adding setSizePolicy, I've tried the RawWidget approach, and my table just sits there stubbornly with a fixed size. What can I do?

in my main Python script:

        ... other python stuff ...
        import tableview   
        app = QtApplication()
        app.resolver.factories['TableView'] = tableview.table_view_factory
        ... other python stuff ...

tableview.py:

from atom.api import (Typed, ForwardTyped, observe)
from enaml.core.declarative import d_
from enaml.widgets.control import Control, ProxyControl
from enaml.qt.qt_control import QtControl
from PySide.QtCore import (QAbstractTableModel)
from PySide.QtGui import QTableView, QSizePolicy

class ProxyTableView(ProxyControl):
    declaration = ForwardTyped(lambda: TableView)
    def set_model(self, model):
        raise NotImplementedError

class TableView(Control):
    proxy = Typed(ProxyTableView)
    tableModel = d_(Typed(QAbstractTableModel))
    @observe('tableModel')
    def _update_proxy(self, change):
        """ An observer which sends state change to the proxy.
        """
        # The superclass handler implementation is sufficient.
        super(TableView, self)._update_proxy(change)    

class QtTableView(QtControl, ProxyTableView):
    widget = Typed(QTableView)
    def create_widget(self):
        self.widget = QTableView(self.parent_widget())

    def init_widget(self):
        super(QtTableView, self).init_widget()
        self.widget.setSortingEnabled(False)
        self.widget.setSizePolicy(QSizePolicy.Expanding,QSizePolicy.Expanding)
        d = self.declaration
        self.set_model(d.tableModel)

    def set_model(self, model):
        self.widget.setModel(model)

def table_view_factory():
    return QtTableView 

See my code in #65

It adds an icon that shows up in the window titlebar; but the icon that shows up in the taskbar is this:

I am using Anaconda Python 1.6.0 with enaml 0.7.19 on Windows 7.

Because Validator has been changed, there also needs to be a change in https://github.com/nucleic/enaml/blob/master/examples/tutorial/employee/phone_validator.py . The function:

def validate(self, text, component):

should be:

def validate(self, text):

And the return value should be only just a boolean, so lines 31 and 37 should be return True and line 38 should be return False

This of course makes it so that the phone number formatting won't work, and would need to be implemented in some other way.

Is it gone for good, or coming back eventually?

The dock area tool bars segfault on OSX with this error:

(enaml)Ss-MacBook-Pro:enaml Chris$ enaml-run examples/widgets/dock_area.enaml
2013-07-05 14:14:15.655 python[28759:707] *** WARNING: Method userSpaceScaleFactor in class NSView is deprecated on 10.7 and later. It should not be used in new applications. Use convertRectToBacking: instead.
QPainter::begin: Widget painting can only begin as a result of a paintEvent
QPainter::translate: Painter not active
Segmentation fault: 11

GDB indicates a problem with QGraphicsDropShadowEffect:
Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x0000000000000000
0x0000000111ad68e9 in QGraphicsDropShadowEffect::draw ()
(gdb) backtrace
#0 0x0000000111ad68e9 in QGraphicsDropShadowEffect::draw ()
#1 0x0000000110e15c32 in sipQGraphicsDropShadowEffect::draw ()
#2 0x000000011156f19d in QWidgetPrivate::drawWidget ()
#3 0x00000001115700f2 in QWidgetPrivate::paintSiblingsRecursive ()
#4 0x000000011156faf7 in QWidgetPrivate::drawWidget ()
#5 0x00000001115700f2 in QWidgetPrivate::paintSiblingsRecursive ()
#6 0x000000011156ff1e in QWidgetPrivate::paintSiblingsRecursive ()
#7 0x000000011156faf7 in QWidgetPrivate::drawWidget ()
#8 0x00000001115700f2 in QWidgetPrivate::paintSiblingsRecursive ()
#9 0x000000011156faf7 in QWidgetPrivate::drawWidget ()
#10 0x00000001115700f2 in QWidgetPrivate::paintSiblingsRecursive ()
#11 0x000000011156faf7 in QWidgetPrivate::drawWidget ()
#12 0x00000001115700f2 in QWidgetPrivate::paintSiblingsRecursive ()
#13 0x000000011156faf7 in QWidgetPrivate::drawWidget ()
#14 0x00000001114cf397 in -QCocoaView drawRect:

Disabling the drop shadow eliminates the segfault.

the preview app example as demo'd in Chris' talk is missing from the repo

The examples/widgets/FileDialog.enaml file fails because of incompatibility between PySide and PyQt:

File "/Users/cwebster/src/enaml/enaml/qt/qt_file_dialog.py", line 30, in exec_dialog
    path, selected_filter = QFileDialog.getOpenFileNameAndFilter(
AttributeError: type object 'PySide.QtGui.QFileDialog' has no attribute 'getOpenFileNameAndFilter'

PySide only supplies getOpenFileName and related functions, without the option to return the filter as well.

The << operator is great for putting expressions into the view. For instance if the model contains a property that is a floating point number, the view can decide how to format it and will automatically be updated.

But I would like to have the auto-update feature of subscription expressions in the model as well; there are derived calculations which depend on the raw model properties that should be managed by the model, not by the view.

Is there a way to do this?

example class:

class ItemWithQuantityDiscount(Atom):
  quantity = Int()
  basePrice = Float()
  def getQuantityDiscount(self):
      # some complicated formula goes here, depends on quantity
  def getUnitPrice(self):
     return self.basePrice * self.getQuantityDiscount()

and in the view I would like to have:

 Label:
    text << '${0:2f} each'.format(model.getUnitPrice())

From http://docs.enthought.com/enaml/instructional/tut_hello_world.html (yeah, i know, that's the old enaml, but I couldn't find the new docs)

Subscription. RHS can be any expression. The expression will be parsed for dependencies, and any dependency which is a trait attribute on a HasTraits class will have a listener attached. When the listener fires, the expression will be re-evaluated and the value of the view property will be updated.

This fails but is valid python:

1 ^ 2

Traceback (most recent call last):
  File "C:\Anaconda\Scripts\enaml-run-script.py", line 9, in <module>
    load_entry_point('enaml==0.7.17', 'console_scripts', 'enaml-run')()
  File "c:\users\chris\development\enaml\enaml\runner.py", line 43, in main
    code = EnamlCompiler.compile(ast, enaml_file)
  File "c:\users\chris\development\enaml\enaml\core\enaml_compiler.py", line 518, in compile
    compiler.visit(module_ast)
  File "c:\users\chris\development\enaml\enaml\core\enaml_compiler.py", line 357, in visit
    method(node)
  File "c:\users\chris\development\enaml\enaml\core\enaml_compiler.py", line 546, in visit_Module
    self.visit(item)
  File "c:\users\chris\development\enaml\enaml\core\enaml_compiler.py", line 357, in visit
    method(node)
  File "c:\users\chris\development\enaml\enaml\core\enaml_compiler.py", line 549, in visit_Python
    py_code = compile(node.ast, self.filename, mode='exec')
TypeError: required field "lineno" missing from expr

as it says on the tin. Add this to 'submit_triggers'.

There is severe overlap of the dock area tool buttons on OSX with a retina display. This might be a "won't fix" if it's due to a bug in Qt's hi-dpi scaling. Haven't yet tested on a non-retina display with OSX.