I just started maintaining a set of embedded Python plugins for a Qt application. I'm also new to both PyQt and Python, so bear with me.
I have an implementation of a QTreeWidget in one dialog where the "expanded" signal is not being caught by the corresponding handler. I have another dialog where it works just fine.
In the problem dialog, I can verify that the connect was successful.
connected = wdg.connect(wdg.treeView_,SIGNAL("expanded(QTreeViewItem*)"), wdg.expanded)
evaluates to True. When I click on the child indicators to expand an item, the [+] signs change to a minus, but nothing else happens. Likewise, when I click on the [-], it toggles back to [+]. I have set the ChildIndicatorPolicy to initially set the indicator to SHOW in both cases.
In the dialog that works OK, when the user clicks on the plus sign, the 'expanded' handler is executed. Only the indicator toggles when it is clicked.
My handler code is simply:
def expanded(self, item):
logging.debug("In expanded handler")
I have a breakpoint at the logging call, but the statement is never reached.
I the failing dialog, I have another signal that's connected immediately before the one above, and it works just fine:
wdg.connect(wdg.treeView_,SIGNAL("currentItemChanged(QTreeWidgetItem*, QTreeWidgetItem*)"), wdg.itemChanged)
Is there anything that could prevent an expanded signal from firing or being caught? Another event perhaps? What should I be looking for? I realize that my nomenclature may be a bit off, and I welcome any correction in that regard as well.
The signal for a QTreeView expansion event is "expanded(QModelIndex)".
Alternatively, consider using the new style signal/slot syntax. I find it much easier than looking up the exact argument type for a particular signal.
wdg.treeView_.expanded.connect(wdg.expanded)
I found the problem. Despite the misleading name, the object is a QTreeWidge. When I replaced the name of the signal from "expanded" to "itemExpanded" and changed the parameter type to a QTreeWidgetItem*, everything worked.
wdg.connect(wdg.treeView_, SIGNAL("itemExpanded(QTreeWidgetItem*)"), wdg.expanded)
Related
Here is my code: (just so you know I am a beginner and I just started this week, though I do have knowledge with other languages and game engines)
func _on_Area2D_area_entered(area):
get_parent().get_node("Level 1/Area2D/Flag").rotation_degrees += 1
What I was trying to accomplish was that the Player GameObject would see if its in the area of the Flag, and if it is, the flag would rotate.
I am not sure where the issue is. I think it is probably in the second line. I provided a screenshot below if I did the setup wrong. I have looked at the other close questions asked on the same topic, but they did not answer my question.
The "Player" GameObject is the one with the script that contains the detection if its in the area2D.
If you want to check if the Area2D is positioned correctly during runtime enable Debug -> Visible Collision Shapes.
If you want to check if _on_Area2D_area_entered is running, add breakpoints (or use print).
Did you get an error?
If there isn't a Node there, this expression will cause an error in runtime:
get_parent().get_node("Level 1/Area2D/Flag")
If you want to be able to check, you can use get_node_or_null and is_instance_valid.
Since you didn't mention any error, I'm going to guess the method is not running.
If the method is not running, the most likely culprit is that - I'm guessing given then name of the method - you connected the "area_entered" signal but intended to connect the "body_entered" signal.
The "area_entered" signal will trigger when another Area2D enters the Area2D. But I only see one Area2D in your scene tree. On the other hand the "body_entered" will trigger when a PhysicsBody2D (e.g StaticBody2D, KinematicBody2D, RigidBody2D) enters the Area2D. In either case you get what entered as a parameter of the method.
Other reasons why the Area2D might not be detecting what you want include no intersection of collision_layer and collision_mask and monitoring being disabled.
And to dismiss a couple possible misconceptions:
The "area_entered" and "body_entered" trigger when the Area2D or PhysicsBody2D respectively enter the Area2D, not every frame they are inside. So rotation_degrees += 1 is not a rotation animation.
You will get notifications of anything that trigger the signals, not just the object to which you connected it. You may have to further filter, e.g. if body == self:.
For people arriving here from search, I want to link a similar case: Enemy is not affected by bullets. And also my full explanation of how to set up physic nodes.
Is it possible to check if a custom shape has been clicked. For instance, how would I check if a piano key, which is not a regular shape, has been clicked. I would assume that you would make an area 2D and make a Collision Polygon 2D, which has your shape, as a child, Then you would send a signal to a script if their was input, and the script would check if it was a click and respond accordingly. I tried this but it is not working. Below is my code. Any help is much appreciated!
func _on_Collision_input_event(viewport, event, shape_idx):
if event is InputEventMouseButton:
if event.is_pressed:
$"RadioCPressed".show()
print("Object Clicked")
else:
$"RadioCPressed".hide()
You have a typo, it should be event.is_pressed() not event.is_pressed. It must be giving you an error on run time.
Assuming it is not giving you an error, it probably means the method is not running at all (You can use a print or breakpoint at the start of the method to confirm). Also, double check you connected the signal. And make sure the Area has input_pickable set to true.
Something else you need to consider if whether or not there is something else getting the input. A common case is that people will use a ColorRect or TextureRect for background, and leave it with mouse_filter set to Stop (which is the default). Even if it is in the background, you need to set mouse_filter to Ignore, because Controls take priority over other nodes for input. See Using InputEvent.
I'm currently working on a program using MFC. The current third party function starts a thread after an action has been completed using MFC (ie. Checking a checkbox, which starts a MFC thread I believe).
The problem occurs when I check the checkbox, at which point the entire program hangs. I read a few interesting discussions on CProgramming and msdn, it seems that the problem occurs because the new third party thread is calling WaitToSomething() when MFC is updating a control.
Something interesting to note:
When I debug the program, the program hangs (aka. repeatedly calls WaitToRead() ) after I check the checkbox and a new thread is trying to start
When I run the program without debugger, the program is fine UNTIL I switch to another window (ie. Internet browser, Notepad, etc)
My hypothesis:
check to make sure that MFC has finished updating the control before starting a new thread
If anyone has any suggestions or solutions, please leave a comment. Thanks.
Edit:
MFC is not thread-safe at object level (only at class level), so problem occurs when two threads work on the same CButton object.
Q: How do I make it thread safe?
A colleague helped me figure out what the problem was.
The reason why it was hanging is because that the control containing the checkbox is a child dialog, and when it finished updating the message never got passed up to its parent (so when 3rd party thread calls WaitFor(), the MFC thread never completes because a parent dialog thinks its child is still updating the controls).
Fix:
Under 'Properties' in the child dialog's control, set the 'Control' flag to true (and if it has children, set the 'Control Parent' flag to true as well).
Hope this helps.
I have a core data document based cocoa app that is working well except for one slightly odd problem.
For some reason, if I make a change to any of my fields the menu/window don't seem to recognize it - ie. the red close button doesn't get the black 'dirty' indicator and the File/Save menu item isn't enabled. However, if I attempt to close the application (via command-Q), I do get the popup asking me if I want to save my changes.
It seems that the document's dirty flag is being set, but the window/menu items aren't reacting to it. I am curious as to where I might look to see why this might be the case. I suspect that it may have something to do with my window not knowing about my ManagedObjectContext...
The only slightly atypical behaviour is that my document's makeWindowControllers method has been overridden and I am adding my window controllers using a call to my document's [self addWindowController:xxx] method. My window controllers subclass from NSWindowController so I had to add my own instance variable to each window controller to hold the ManagedObjectContext, but I suspect that this isn't getting passed to the window/menu. Not sure what the normal pattern is here...
Anyway, any thoughts would be much appreciated. Thanks
From the description it sounds like your UI elements are not actually bound to the document itself. If so, then the UI elements are not observing the document and are not reacting to changes in the document. Check the bindings.
Thanks in part to TechZen, and also re-reading my own question (in particular, where I said "I suspect that it may have something to do with my window not knowing about my ManagedObjectContext") I started to look at the bindings for my WindowController subclass.
As it turned out, I hadn't bound the window outlet for the File's Owner to my actual NSWindow. As soon as I did that, the black dirty dot and the window's menus started behaving correctly.
I have a Glade GUI description file with a GtkTreeView in a GtkHBox in a window; and there's a handler for the row_activated signal. Now, Glade has automatically set the "events" property (inherited from GtkWidget) of that treeview to some value (GDK_POINTER_MOTION_MASK | GDK_POINTER_MOTION_HINT_MASK | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK). And there are two strange things with this:
removing the pre-set value (so that the property is empty) doesn't seem to break the application (at least not with the old GTK 2.10 I have atm).
in fact, an annoying bug I has seen before (where the treeview items would not correctly react to expand or collapse clicks) is now gone!
I have yet to test this with a newer GTK version, but the question is already there: exactly what is the purpose for this events property? And why does Glade automatically and unnecessarily set it to some value? Does this have some side effects I'm not aware of?
It's a bug in glade, it always sets the event property of widgets it create. It has no notion of the default value of a property so it always sets it.
Doesn't this mask indicate the events you're willing to receive? In this case, you'll probably want to receive notification that the user has clicked or double-clicked an item in the GtkTreeView, and you'll want to register callbacks to handle these events.
me.yahoo.com/a/kUQ7zeQ: but even if I set the property to an empty string as mentioned, the row_activated handler is still called when I double-click on a row (or press Enter or Space). So the treeview still gets events...