I am new here and would be grateful If anybody helps me. recently I have been working on state machine diagrams and UML language in general. I have been using Enterprise Architect (EA) V11 for drawing some state machine diagrams like drawing states, triggers, guards and events. It is known that there are two types of triggers 1. transition triggers that cause a transition from a state to another 2. inner triggers that doesn't cause a transition. EA supports only three types of inner triggers ( Entry, Exit, Do ) because of this I can't put in my own inner triggers as an example if enter button is pressed turn on a device. Another thing that I can't write commands that are going to be executed inside the state.
So I have two questions 1. How to name my own inner triggers? 2. how to write commands inside a state?
Any help please...
I have found the solution. To create an inner trigger for a state, a self transition will do the trick. Create a transition connector issuing from and terminating in the state element and then modify its properties to be of kind internal. Then commands can be added by editing the Effect textbox.
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I am facing issue with callbacks. I have 3 drop downs, one scattermap , one table and one slider on the screen and they all need to work in tandem and i have 5 call backs. When i execute the application all my callbacks associated with these controls execute in random order. After that when i click on scattermap it may or may not work. Say we assume it worked. Then i can navigate all around without any hassle. Then if i execute the application then click on the scattermap then as i mentioned it may or may not work. Say suppose it didn't work this time. If so is the case it will not work at all no matter what i do and simulaneously one specific dropdown also becomes dysfunctional. However if click any of the other two drop downs then evrything will start functioning as normal.
I have digged really deep into this and figured out that this has nothing to do with my code. The underlying issue is that when the click doesn't work the reason the reason behind that is the callback isn't getting triggered. I found out this by applying some debugging techniques and i am 100% sure the callback is not firing. Can anyone help me resolve/understand this please.
I'm still pretty new to scripting in Unity3D, and I'm following along with a tutorial that uses GUI.Button() to draw a button on the screen.
I am intrigued by how this function works. Looking through the documentation, the proper use of GUI.Button is to invoke the function in an if statement and put the code to be called when the button is pushed within the if statement's block.
What I want to know is, how does Unity3D "magically" delay the code in the if statement until after the button is clicked? If it was being passed in as a callback function or something, then I could understand what was going on. Perhaps Unity is using continuations under the hood to delay the execution of the code, but then I feel like it would cause code after the if statement to be executed multiple times. I just like to understand how my code is working, and this particular function continues to remain "magical" to me.
I don't know if it's the right term, but I usually refer to such system as immediate mode GUI.
how does Unity3D "magically" delay the code in the if statement until
after the button is clicked?
GUI.Button simply returns true if a click event happened inside the button bounds during last frame. Basically calling that function you are polling: every frame for every button asking the engine if an event which regards that button (screen area) is happened.
If it was being passed in as a callback function or something, then I
could understand what was going on
You are probably used to an MVC like pattern, where you pass a controller delegate that's called when an UI event is raised from the view. This is something really different.
Perhaps Unity is using continuations under the hood to delay the
execution of the code, but then I feel like it would cause code after
the if statement to be executed multiple times.
No. The function simply returns immediately and return true only if an event happened. If returns false the code after the if won't be executed at all.
Side notes:
That kind of system is hard to maintain, especially for complex structured GUI.
It has really serious performance implications (memory allocation, 1 drawcall for UI element)
Unless you are writing an editor extension or custom inspector code, I'd stay away from it. If you want to build a menu implement your own system or use an external plugin (there are several good ones NGUI, EZGUI,..).
Unity has already announced a new integrated UI System, it should be released soon.
Good question. The unity3d gui goes through several event phases, or in the documentation
Events correspond to user input (key presses, mouse actions), or are UnityGUI layout or rendering events.
For each event OnGUI is called in the scripts; so OnGUI is potentially called multiple times per frame. Event.current corresponds to "current" event inside OnGUI call."
In OnGUI you can find out which event is currently happening with >Event.current
The following events are processed link:
Types of UnityGUI input and processing events.
-MouseDown
-MouseUp,mouse button was released
-MouseMove,Mouse was moved (editor views only)
-MouseDrag,Mouse was dragged
-KeyDown, A keyboard key was pressed
-KeyUp A keyboard key was released.
-ScrollWheel The scroll wheel was moved.
-Repaint A repaint event. One is sent every frame.
-Layout A layout event.
-DragUpdated Editor only: drag & drop operation updated.
-DragPerform Editor only: drag & drop operation performed.
-DragExited Editor only: drag & drop operation exited.
-Ignore Event should be ignored.
-Used Already processed event.
-ValidateCommand Validates a special command (e.g. copy & paste).
-ExecuteCommand Execute a special command (eg. copy & paste).
-ContextClick User has right-clicked (or control-clicked on the mac).
Unity GUI has much improved lately and is quite usefull if you want to handle things programmatically. If you want to handle things visually, i recommend looking at the plugins heisenbug refers to.
If you decide to use unity gui, i recommend using only one object with ongui, and let this object handle all your gui.
I have been using the MVVM Light Toolkit to help learn the MVVM pattern. However, I have not been able to solve the problem of usercontrols within controls scenario.
For example, in a Timesheet application, lets say we have a control called NewUnitOfWork. When it first loads, a panel with a ListBox with a list of projects is loaded as the Content of the NewUnitOfWork. The user clicks on one. A new panel is swapped in with a ListBox containing the possible tasks for that project. A task is selected and a new panel is loaded which will contain controls to input data for the chosen task of the chosen project.
So, we have the selected item in one usercontrol being passed to the other two user controls, which are, in turn swapped in as the Content of the NewUnitOfWork control (or window).
If each control has its own ViewModel, we need to pass the selected value from one ViewModel to the next etc.
I have got it working in a single user situation using global variables (via a "service"). However, there are concurrency issues with that and it is not a good solution. It's sub-par.
I have seen many times the suggestion on this forum to have on ViewModel as a member of another ViewModel. Whilst this solves the problem at hand, I believe it is a violation of the MVVM pattern. Another ViewModel is not UI-related functionality that the ViewModel shoule be directly.
So. Has anyone found a clean MVVM-complying way to do this sort of thing?
Cheers
Please always keep in mind that MVVM is just a pattern and it is designed to help you separate your UI and logic. Do not be afraid to “violate the pattern” if it helps to increase testability or maintainability of the application.
Having a master ViewModel with several child ViewModels is very handy if you have a complex UI. The main ViewModel may be responsible for handling the top level UI controls and for coordination of the child VMs, while other ViewModels are responsible for communication with the sub regions of your UI.
Moreover, if you have a really complex UI with the multiple nesting UI layers, you can implement an infrastructure to automatically cascade all the events from master to child VMs.
And of cause, you may try to use one of the more advanced MVVM frameworks. For example Catel implements pretty comprehensive model to resolve such situations with nested VMs.
I don't see a problem with ViewModels referencing other ViewModels (based on my experience with TreeViews). Have a look at any article about TreeView and MVVM. You will see that each node is a ViewModel, that references a collection of child nodes, which are ViewModels. Trying to do that without VM-VM references would be a nightmare.
Josh Smith
http://www.codeproject.com/KB/WPF/TreeViewWithViewModel.aspx
I have been using the following setup:
A 'master' VM with a 'collection' VM and a 'details' VM as nested properties.
The master VM is tied to a View that is used as a master-detail form. This master-detail View is composed from two other Views.
I find it a very neat setup because it allows me to put search criteria in the master View(Model) and keeps the other View(Model)s clean.
I can't see how this would break the pattern.
Caveat: I'm still struggling with proper MVC in Eclipse plugin development, so if you see anything here that is most likely causing me more pain that I should be enduring, please let me know.
The question:
I have a View with a JFace Tree Viewer and a Table (not a table viewer... that will be changed down the road).
I have an action that is initialized with a reference to the View (this seems terrible to me, but I don't yet know how to do it the right way). When the action is run -- via a button on the view -- the action:
1) gets the Tree Viewer from the View
2) gets the underlying model
3) creates a Job
a) inside the job, loops over the model and does various things to it, including adding additional children into the model
b) uses a function exposed in the view that "clears" the Table in the view
4) adds a JobChangeListener that implements "done()".
a) inside the done() method, it expands the treeviewer via this code:
loadMethodsJob.addJobChangeListener(new JobChangeAdapter(){
public void done(IJobChangeEvent event){
view.enableActions();
view.getTestsViewer().expandAll();
}
});
Inside the Job, whenever I attempt to access the elements in the viewer, I get Invalid Thread Access errors. I believe I understand why I get them when running inside the job, but I'm not sure how to work around them correctly if I can't interact with the widgets in the job change listener. I can get it to work if I wrap every interaction with the widgets in a getDisplay().synchExec(....), but I seem to remember reading that this is not preferable.
I feel like I'm on the cusp of a big leap in understanding with Eclipse SWT, so I appreciate any guidance in getting there.
Any UI component in SWT can be accessed only by a UI thread.
Since the done method of the job runs in a separate non-UI thread, the invalid thread access is fired.
By wrapping every interaction in a Display.syncExec , you are making sure that it runs in the display thread (The UI thread).
There shouldn't be any problem with the above approach.
My application is using workflow designer rehosting to let end-users develop workflows. I have an Activity available that requires the user set some state. To accomplish this, in the designer I override Initialize(Activity) and show a form which I then use to set values in my Activity. This is for setting the state when the Activity is initially added. I also have a double click event handler in the designer in case they need to edit that state later.
I now have a situation where, depending on the values in the form, I may need to add or remove a child activity. I've been successful in adding the activity, but not always in getting it to show up in the designer.
When Initialize is called, there are no child activities. I may need to add a child Activity. At this point, it works fine and shows up in the designer. The problem happens when they edit it later by double clicking. In my designer, I override OnActivityChanged to detect this. I make the same call to add a child, however the designer is not getting updated. Oddly enough, when the situation is such that the child is removed, the view updates fine.
Stepping through with the debugger shows that I am adding a child activity to the Activities collection. Normally when I have problems updating the view, I can make a call to IComponentChangeService.OnComponentChanged, but I can't seem to find a way to make this work.
Any suggestions?
It looks like I needed to use RemoveActivities and InsertActivities in the designer. It seems as if the designer doesn't listen to list change events on the Activities list. Does anyone know if this is how it's supposed to work?
Have you tried this in your OnActivityChanged event handler?
TypeDescriptor.Refresh(e.Activity);
For my situation, I determined I needed to use RemoveActivities and InsertActivities.