I have been reading up on the use case for calling #model.touch and how you can have that bubble by passing , touch: true when setting up your associations in the model. I think I understand everything that is happening there.
What I wanted to ask is that if at no point in your code do you call .touch will having associations that include , touch: true do anything?
I am trying to familiarise myself with a new codebase that has a handful of places that have the association set to allow touch to bubble but there is nowhere in the code that .touch is ever called. I want to try and figure out if these are redundant properties of the association or if something else can hit .touch that would get use out of the bubbling of it.
Thanks in advance for any help.
Relevant Links
http://api.rubyonrails.org/classes/ActiveRecord/Persistence.html#method-i-touch
Do'h!
A little more digging led me to this: When is touch for a belongs_to in Rails triggered?
Which contains the following quote:
:touch If true, the associated object will be touched (the updated_at/on attributes set to now) when this record is either saved or destroyed. If you specify a symbol, that attribute will be updated with the current time in addition to the updated_at/on attribute.
The saved/destroyed part of this answered my question.
Related
Is there a symbolic breakpoint or something that will trap the following warnings, so that the erroneous code can be more easily found?
Attempt to present <> on <> while a presentation or dismiss is in progress.
Trying to dismiss the presentation controller while transitioning already. (<>)
I don't have a specific problem to solve, just looking for an answer to this question, which could just be "no".
When these errors occur, how do you find out the present/dismiss call causing the problem and/or the present/dismiss that is in progress?
Maybe a little more context would help us answer your question ?
Are you using UIViewControllerAnimatedTransitioning ?
When are you having this issue happening ?
If you want to debug, you can use UINavigationControllerDelegate method for your convenience :
- navigationController:willShowViewController:animated: or
navigationController:animationControllerForOperation:fromViewController:toViewController:
If you're not already using it for your animation.
The best I've found so far is to run with Allocations instrumentation and "Record reference counts".
Then you can find the specific instances referenced in the logs by their address.
This will have recorded the stack traces when that object was created, presented, etc, as they all involve changes in reference count.
I have a form that is supposed to create an entity of type Load, but for some reason, doesn't seem to be actually passing or seeing any of the data related to associations of the entity (load.user, load.client, etc). This all used to work fine but stopped working at some point during a bunch of refactoring (that didn't change any of the fields in any of the models). Now all of the forms in my website have broken the same way and I have no clue where to even look to start fixing it.
From the view, I submit the form for a new Load, printing out the data everywhere I can along the way. Printing out the data being sent to the server before it's sent shows all the data is there like it should be. Printing out Form.form(Load.class).bindFromRequest() in the controller shows the form's data contains everything needed, for example, the value user.id=1 is in the data. However, there is also a validation error saying that the user is missing. How can this be?
Form(of=class models.Load, data={ a bunch of stuff, user.id=1, a bunch more stuff}, value=None, errors={=[ValidationError(,Logged in user is missing or invalid.,[])]})
The validation error is being generated by public String validate() in the Load class, which is simply checking if(user==null) and returning that string if it is. I should note that every form that submits multiple entities (for example, submitting a Dock and then also the Dock's Location) only saves the main entity (in this example, the Dock) and ignores all others (the Dock's Location is never saved, even though Dock cascades in the model to also save the Location). All of our form fields are labelled correctly, this code did used to work at some point before it mysteriously stopped working!
So why did all of my forms suddenly stop correctly dealing with anything but the main model for the form? It is as if they cannot even "see" the data contained in bindFromRequest(). If I print out a variable in the validation method of Load, such as this.status, it prints the correct thing. But if I try to print something like this.user.id or this.client.id I get a null pointer error. Where is the code in Play that actually interprets the data (user.id=1) and turns it into the User associated with the Load, and how could it be breaking?
Edit: Also, yes, I did try "play clean", it was the first thing I tried since usually it fixes weird errors like these! But this time, no dice.
Edit2: I'm including the html from the form, in case it is helpful.
<input type="text" id="user_id" name="user.id" value="1" class="idfield">
Edit3: The only change I made during the refactoring that might have influenced this is that I had to make some setter methods like Load.setBroker() because the ones that are supposedly generated by Play didn't work. For example, load.broker=aBroker would not have set the Load's Broker before, so I had to make a public void setBroker(Broker broker) method in Load. Does Play use the auto-generated setters to bind the data? Could overwriting them cause problems?
Whoops, I figured it out. It was the setters I had written. Some of them were set to private purely by mistake, and apparently this was preventing Play from setting the values when binding the data. Changed them all to public and the mystery error vanished.
I was thinking how could I make my own property attribute, for example:
#property(retain,nonatomic,'myAttribute') int numberOfWheels
#property('unique',nonatomic) NSString productCode
but when I try to get a help from Xcode pressing command button or option button nothing happens
I was looking in this page and many others but no one ask how to make your own attribute, most of then just asking about how to use property attributes or difference between them
I dont know if its possible to make a new attribute, but if its true, could someone help me
The only way to do this is to modify the compiler directly to add this functionality. I have no idea where you'd begin to do that, except to point you to http://llvm.org and say "good luck".
I want to create a new object so as to instantiate and use it several times;
For example, if I want to create an object that has a label and a button inside, how do I? I created a new NSObject but inside it has nothing, then how do I make everything from scratch since there was a viewDidLoad for example (obviously, since it has a view)?
thanks!
Your questions lead me to think that you're really just starting out. There's nothing wrong with that, but rather than trying to summarize several megabytes of documentation in a few paragraphs, I'm just going to point you to the iOS Starting Point. I think that you're just trying to create a container that can hold other UI components? If so, use a UIView for that. However, don't jump in and try to get something specific done without first reading through some of the Getting Started documents -- you'll just end up back here, and we'll just point you back to the docs. You might like the Your First iOS Application guide, as that lets you get your feet wet but explains things along the way.
After setting up a table model in Qt 4.4 like this:
QSqlTableModel *sqlmodel = new QSqlTableModel();
sqlmodel->setTable("Names");
sqlmodel->setEditStrategy(QSqlTableModel::OnFieldChange);
sqlmodel->select();
sqlmodel->removeColumn(0);
tableView->setModel(sqlmodel);
tableView->show();
the content is displayed properly, but editing is not possible, error:
QSqlQuery::value: not positioned on a valid record
I can confirm that the bug exists exactly as you report it, in Qt 4.5.1, AND that the documentation, e.g. here, still gives a wrong example (i.e. one including the removeColumn call).
As a work-around I've tried to write a slot connected to the beforeUpdate signal, with the idea of checking what's wrong with the QSqlRecord that's about to be updated in the DB and possibly fixing it, but I can't get that to work -- any calls to methods of that record parameter are crashing my toy-app with a BusError.
So I've given up on that idea and switched to what's no doubt the right way to do it (visibility should be determined by the view, not by the model, right?-): lose the removeColumn and in lieu of it call tableView->setColumnHidden(0, true) instead. This way the IDs are hidden and everything works.
So I think we can confirm there's a documentation error and open an issue about it in the Qt tracker, so it can be fixed in the next round of docs, right?
It seems that the cause of this was in line
sqlmodel->removeColumn(0);
After commenting it out, everything work perfectly.
Thus, I'll have to find another way not to show ID's in the table ;-)
EDIT
I've said "it seems", because in the example from "Foundations of Qt development" Johan Thelin also removed the first column. So, it would be nice if someone else also tries this and reports results.
I use Qt 4.6.1 in PyQt and the problem is still here. Removing "removeColumn(0)" solves the issue.