I am assuming, though I don't know for sure, that while a react-dnd drag is going on, it is possible for the handler of an async event [such as a setTimeout handler or the receipt handler of a websocket message] to get scheduled on the event loop. Please correct me if I am wrong and the event loop is not yielded while a drag is in progress.
If in fact the event loop can be yielded to async event handlers in the middle of a drag, and if it so happens that the event handler needs to mutate the drag source, how should this situation be resolved? Perhaps the mutation of the drag source in the middle of a drag is disallowed by the react-dnd framework. If such a mutation is allowed, confusion could ensue for the user.
A simple strategy to follow in such a case would be to cancel the drag and inform the user that a higher priority event needed to be taken care of that pre-empted the drag. Is it possible to cancel the drag programmatically in such cases?
Many thanks.
Azad
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I have several display objects in createjs and event using easeljs i want to prevent from mouse and touch event passing through them.
i want like a easy one liner like .mouseEnabled or .mouseChildren is there something will will prevent any other interaction for the objcts below this. i can try adding all events to a backdrop movieclip which tint background color and prevent default and stopPropogation will that help?
so how to i prevent from any type of interaction taking place in canvas just by placing a displayobject that's like wall which will not allow the other displayobjects from getting click, mouseover or touch events.
You can add obj.mouseEnabled= obj.mouseChildren = false; to any you don't want to receive events.
If you just want to block events with a child on top, simply add a mouse handler to it.
cover.on("click", function(){});
You don't need stopPropagation, since that will only prevent events from bubbling in the current hierarchy (ie, surfacing an event to its direct parent). Events do not "pass through" objects that have mouse handlers on them.
Hope that helps!
I've had several occasions in my selenium tests where I decided to use Selenium's click_and_hold() (source code here) method on some element. The source code makes it look like it will stay pressed indefinitely but there are definitely some actions, such as a simple click, that cause the held click to be released. Obviously calling release will release the held click too, but does anyone have a grasp on exactly what actions/conditions (either from the script or the page itself) will cause the held click to be released?
I've linked to the documentation for the python bindings, but I assume this would be the same no matter what language is used to write the script. Please let me know if this assumption is incorrect!
release()
release(on_element) releases a held mouse button on an element. If on_element is None releases on current mouse position which is defined as:
def release(self, on_element=None):
"""
Releasing a held mouse button on an element.
:Args:
- on_element: The element to mouse up.
If None, releases on current mouse position.
"""
if on_element:
self.move_to_element(on_element)
if self._driver.w3c:
self.w3c_actions.pointer_action.release()
self.w3c_actions.key_action.pause()
else:
self._actions.append(lambda: self._driver.execute(Command.MOUSE_UP, {}))
return self
release() is invoked by default by different methods of the ActionChains implementation. Some of them are as follows:
release(): Releasing a held mouse button on an element.
drag_and_drop(source, target): Holds down the left mouse button on the source element, then moves to the target element and releases the mouse button.
drag_and_drop_by_offset(source, xoffset, yoffset): Holds down the left mouse button on the source element, then moves to the target offset and releases the mouse button.
click_and_hold()
click_and_hold() holds down the left mouse button on an element.
So you saw it right, the source code confirms the same that it will stay pressed indefinitely unless release() is directly invoked or invoked through other methods. However there can be other actions / events which may cause the hold down left mouse button to be released implicitly. These actions / events can be a result of any of the HTML DOM Events. HTML DOM events allow JavaScript / AjaxCalls to register different event handlers on elements in an HTML document. Some of the mostly encountered events are:
HTML DOM UiEvent: Events that are triggered from the user interface belongs to the UiEvent Object.
onload Event: The onload event occurs when an object has been loaded.
onresize Event: The onresize event occurs when the browser window has been resized.
onscroll Event: The onscroll event occurs when an element's scrollbar is being scrolled.
HTML DOM FocusEvent: Events that occur when elements gets or loses focus, belongs to the FocusEvent Object.
onblur Event: The event occurs when an element loses focus
onfocus Event: The event occurs when an element gets focus
onfocusin Event: The event occurs when an element is about to get focus
onfocusout Event: The event occurs when an element is about to lose focus
The Event Object: All event objects in the DOM are based on the Event Object.
onchange Event: The onchange event occurs when the value of an element has been changed.
HTML DOM MouseEvent: Events that occur when the mouse interacts with the HTML document belongs to the MouseEvent Object.
onmousedown Event: The onmousedown event occurs when a user presses a mouse button over an element.
onmouseup Event: The onmouseup event occurs when a user releases a mouse button over an element.
HTML DOM DragEvent: Events that occur when elements are dragged and/or dropped, belongs to the DragEvent Object.
ondrag Event: The ondrag event occurs when an element or text selection is being dragged.
ondragstart Event: The ondragstart event occurs when the user starts to drag an element or text selection.
HTML DOM TransitionEvent: Events that occur when a CSS transition runs, belongs to the TransitionEvent Object.
transitionend Event: The event occurs when a CSS transition has completed
key_up()
The key_up() method also releases a modifier key. As an example:
ActionChains(driver).key_down(Keys.CONTROL).send_keys('c').key_up(Keys.CONTROL).perform()
This usecase
Without any visibility to your usecase of implementing click_and_hold() it is to be noted that, key_down() is a method which performs a modifier key press and it does not release the modifier key and subsequent interactions may assume it's kept pressed. Note that the modifier key is never released implicitly. Either key_up(theKey) or send_keys(Keys.NULL) must be called to release the modifier.
Generally any action that results in a mouse up event being called.
Click will call a mouse down event and then a mouse up event (As shown in the Code)
Click_and_hold() will only perform the mouse down part. If you then call anything else that triggers the mouse up event, the mouse click will be released.
Remember selenium is just passing a list of actions over to the driver binary that is controlling the browser using the JSON wire protocol. The commands you use in code are translated into JavaScript actions before being passed over the wire so the driver binary controlling the browser probably doesn't have much in the way of context of exactly what the original commands before they were broken down were.
Here's the problem: I have a React-Native/Redux app. I need to make sure I can lock the screen (display a modal, really) after X minutes of app inactivity (theoretically someone may have their screen "always on", so I can't rely on the screen turning itself off).
My proposed solution: I want to detect when any touch event happens. I don't want to interfere with them or do anything about it other than reset a setTimeout. But I just want to know when the screen is touched at all.
Displaying the modal itself isn't an issue and is already working. I also have it display the modal if the app leaves the foreground for any reason. I just need the timeout.
I've tried using a TouchableWthoutFeedback that wraps the whole UI and that sorta works, but it doesn't receive any event when a Touchable is farther down the component tree and handles the event. But I've also only used onPressIn and I'm unsure if anything else on it will work as needed. I've looked briefly at PanResponder but that looks a bit more complex than I might need? Not sure on that one, yet.
I'm open to other suggestions, but the only other thing I can think of is having literally every other action in the app (even ones I haven't created yet) send an dispatch up the redux flagpole, and that seems very heavy-handed and prone to error.
is this feasible? What are my options if it's not?
I found the solution. It's to add a onStartShouldSetResponderCapture callback as a prop on a containing View. I can return false in this callback but still notice all the touch events that come through. The Capture portion is important because it gives you access to the event before a "real" touchable can get to it.
Then, in the callback, I just clear and re-create the timer.
I'm trying to program something to read voltage from the Labview ULx library and add the voltage into an array. I tried to do so using an event structure while setting a boolean button 's mechanical action to "Latch when pressed". However, the "Latch when pressed" option seems doesn't work and the program reads the voltage and adds it to the array correctly and it freezes.
front panel
Block diagram:
When you use a Value Changed event with a latched Boolean control, you need to read the control's value inside the event structure in order to reset the latch.
Just move the Sample control's terminal inside the event structure, then it should work as you expect.
Tip: you are free to use the Latch When Pressed action if you want, but the standard action for UI buttons in the OS (Windows etc) is actually Latch When Released. You can check this by clicking on a button, dragging the mouse pointer off the button and then releasing it - the button shouldn't operate. You might want to decide which one makes more sense for your application.
I am looking to use the nativeWindow.startMove() to drag the chrome around, but with a touchEvent rather than a mouse event. I'm not sure if this is at all possible after extensive googling.
I have also tried to dispatch manual mouseEvents when a touchEvent is fired.
Ultimately is the startMove function strictly a mouse only driven function, or can I force this to occur through a touchEvent?
Any input would be most grateful :)
You can manually change x and y properties of the NativeWindow in response to TouchEvents, not necessary using startMove().