best way to pass core data values - core-data

Im developing a golf score recording app with three view controllers.
The first view controller is a table view controller that has each round that you play via an add round button. When you click a golf round(cell) it takes you to a new view controller that has 18 buttons correlating to each hole of that round. When you click on a hole button (i.e. Hole 1), it then pushes you to a new 3rd view controller where you can record values such as the Par of that hole, the yardage, and then also text fields to input each players score(all this being stored via core data).
Here is my dilemma. Im using core data to persist all the data. Im curious on what the best way to populate text labels on my 3rd view controller with information from my first view controller. Right now I am using the prepareForSegue function to create instances of the new view controllers and then setting the properties of the new view controllers via the prepareForSegue function.
This works just dandy. however, when i get to the third View controller i want to populate some of my fields with some of the data that corresponds to that round. And because the third VC is not a table view I'm lost at how to make sure its fetching the correct data from the correct corresponding indexPath. Right now I'm just passing values from the tableview through properties in the 2nd VC, and then passing those properties again to the 3rd VC. Is there a way i can just do a fetch request on a specific index path if I'm not on the tableview VC?
I hope that makes sense.

Your data structure probably looks something like this (or should):
Course (.rounds) <------>> Round (.course)
Round (.holes) <------>> Hole (.round)
You press on a row in the list of holes, simply pass the select Hole to the final view controller. If you need any information from any of the superordinate entities, simply use dot notation.
NSString *nameOfCourse = self.hole.round.course.name;
No need to fetch, no need to communicate with any other view controllers! How swell is that?

Related

Passing an object from a tabbarController to its subviews

I am trying to pass a simple core data objects info from a tabBarController to its subviews so that they each reference a different attribute of that object. As a newbie, I'm not sure even where to start. It doesn't seem to be as simple as passing the data from one tableView to another...
Thank you for any help.
If you are sharing the same object between (most of the) the view controllers of your tab bar controller, maybe the best architecture for this would be to have one central data object.
A typical pattern is a singleton, some kind of data manager that provides the object, but maybe that is overkill. Another is to keep references to all view controllers and update them one by one when something changes - also not very elegant.
What you really want is something like a global variable. You could (ab)use your app delegate (just give it a property that points to the object) or if you prefer even your tab bar controller (make a subclass, give it a property). In the latter case, every view controller could then get the object like this:
NSManagedObject *object = [(MyCustomTabBarController*)self.tabBarController object];
For example, you can check for changes and refresh your views in viewWillAppear.
A UITabBarController should be handling other view controllers, not handling data objects. How does the tab bar controller get the object reference in the first place? And what is the object you're sharing?
Let each of your subordinate VC's keep a pointer to the object, and then they can each follow the appropriate keypath to get to the entities they're designed to handle.
Tim Roadley's book Learning Core Data for iOS, in chapters 5 and 6, shows how to pass an object from one view controller (a table view) to a detail view. It doesn't sound like that's what you're asking, but just in case...
In response to comment:
I'm looking at a tableview, tap a cell, and then a tab bar controller slides in? That's not the usual visual metaphor for a tab bar; it's meant for changing modes for the entire program. See the Music app for a typical example: songs, playlists, artists.
But if you really need to do it that way, try this (I'm assuming you're using storyboards):
In prepareForSegue: in your tableview controller, tell the destination (tab bar controller) what object it's working with.
In the tab bar controller's -viewWillAppear, tell each of its tabs about the attribute: self.frobisherViewController.frobisher = self.myWidget.frobisher.
You could instead tell each of the component tabs about the top level object: self.frobisherViewController.widget = self.myWidget. But I like the first approach better because there is less linkage. The frobisherViewController now would need to know about both widgets and frobishers.
This ended up being very simple. I was trying to call the object in the child views initWithNibName which doesn't work. I ended up creating a setObject function and calling the properties I wanted in viewWillAppear.
Hope this helps someone.

displaying a list on screen with orchard

Using orchard cms 1.6 I have a table in my db 'cars'. I want to display the column 'CarName' from the table, as a list on screen with all the records from the table.
carname1
carname2
carname3
When the user clicks on their link it will bring them to that page.
I know how to do this from the view e.g.
#T("Cars")
but I would like to try and create a content type which shows this list.
Content type seems to be all UI related. Im not sure how to take a table and display a column as a list on screen through the content type...any idea on how to do this?
then I can choose to show the content type as a form and the user can view it from the main menu.
thanks
It looks like you want to create a content type called Car, possibly with a CarPart and a record class CarPartRecord (perhaps refactor your Car class to CarPartRecord to follow Orchard's naming conventions). Make sure CarPartRecord derives from ContentPartRecord.
To render a list of Cars, you could use a Projection that renders a list of cars. A Projection renders content based on a Query, which you configure using the dashboard.
Alternatively, you could create a controller that leverages IContentManager to query all Car content items, and returns a view to render them in a table.
For each Car content item, use Html.ItemDisplayLink to render a link to its details page.

Opening different xpages forms from a view panel

I have an Xpages application that pulls data from another .nsf file. I have a view panel linked to a view in that db. The view has documents with several different forms in it. I want to be able to open each document in it's own form(xpage).
How do I write a computed At Runtime, open selected document using: statement that will select the correct Xpage to present the document.
If you use the Data View component instead of a View Panel, you can compute the pageName attribute, referencing the var attribute to return a different value for each row based on the document that row represents. The flexibility of the Data View component also makes it easier to make your app look more like a modern web application and less like an Excel spreadsheet. As an additional bonus, the mobile theme invokes a renderer that makes each Data View instance look like a native mobile list, so using Data Views instead of View Panels simplifies mobile development.
You have 2 options:
use "use xpage associated with form" and edit the form's property
use a SSJS formula to compute the Form. You provide a variable name in the view control var to access a view row as XSPViewEntry. If the Form is in a view column even one you don't display you use .getColumnValue otherwise getDocument.getItemValueString
Does that work for you?
Maybe this mothed can help you: Unable to get document page name for
Hope this helps
Mark
I had a similar problem today. I use only one form but 3 different xpages for associated with this form. I have 3 different document types in the view. I used rowData the get the type of the document.
try{
var v=rowData.getColumnValue("form");
if(v.indexOf("x")> -1){var page ="x.xsp"}
else if(v.indexOf("y") > -1){var page = "y.xsp"}
else{var page = "z.xsp"}
}catch(e){
var page = "x.xsp"
}
So to your view you can create a column with the value of the form and you can use it.
I have used the extension library Dynamic View control which has an event you can code to get a handle to the NotesViewEntry which was selected. See the demo database page Domino_DynamicView.xsp and the Custom Event Handler tab for an example.
Note, in 8.5.3 (I have not upgraded yet) if you add or edit the eventHandler for onColumnClick it will be added to the XPages source as an xe:eventHandler. It needs to be an xp:eventHandler to work. The way to do it is to copy the code in the source from the exiting event and delete it. Recreate the event and update the code. Then go back into the source and change the tags within the eventHandler to xp:.

Accessing UITextView from another class

I've currently got two view controllers A and B, A uses a segue to push B and this works back and forth nicely, however based on some button presses in view controller B i want to change the text within a UITextView in controller A.
I've had a look at previous posts but i'm a novice at present and was confused by the way in which i should go about doing this.
I'd love to be able to get my head around how interactions are best done between various parts of the app. Also i was wondering if there is a way i can tap into a segue returning to trigger some other code.
Thanks
Edit:
OK perhaps i was a little bit limited with my information, from what i can gather reading other posts they are manually creating a variable for the viewcontroller (A) in viewcontroller (B) then accessing it in the second view controller (B) and setting a variable (property and synthesize) to edit that way, however i have the viewcontrollers embedded in a navigation controller and using a push setup in the storyboard (GUI system). I'm not sure if i have to create a variable to do this or if because they exist in the storyboard there is another way, if someone could just point me in the direction of a post that helps to explain this (i am looking at the moment too) i'd be very grateful.
OK well here's how i got it to work but i imagine there are:
A: Better ways to do it.
B: Changes depending on your setup.
I had my two view controllers embedded in a navigation controller, and used a segue push to access the second view controller each had a different class (all setup in the storyboard thing).
To get it working for me i did the following:
I have a singleton (a class that stores all my data but is global to the app so the variables can be accessed from anywhere in the app) this allows me to have variables that i can access from any view controller. A great tutorial on this can be found here
I then created an NSString variable (passedNote) and updated the value of this variable from the ViewController B, when my button was pressed.
Next when viewController A is loaded (in the viewWillAppear: (BOOL)animated method) i append or replace the value of the textview (dependent on some logic) I have with the global variable (passedNote).
Hope this helps anyone who had the problem.

Updating an AnnotationView Callout after details entered in View Controller that was pushed form the map view

I have a simple maps app with multiple pins on a map view. My intention is to tap a pin, show a callout with an accessory view, push to a Detail View Controller where you can edit that pin/locations details. This all works fine, but once i pop the Detail View Controller the callout on the map view is still there, which i want, but it still has the old uneditied values. How can i refresh/update the callout view once the Detail View Controller is popped?
I am using Core Data with a simple database. I have tried using controllerdidchangecontent, Map View Controller Will Display methods etc but my main problem is identifying which object has been added/updated/deleted and which is the corresponding callout/selected pin.
Any help appreciated...
Not sure if you had find your answer but the way to do it is to extend MKAnnotation class and creating custom annotation and passing them while creating placemarks. Later you can get them from MKAnnotationView's annotation property.
See a good implementation here
http://www.slideshare.net/360conferences/getting-oriented-with-mapkit-everything-you-need-to-get-started-with-the-new-mapping-framework
The only way I could find to update the callout info was to mess directly with the subviews of the callout.
The callout view is the first subview of the annotation view.
In the following example, I update the subtitle.The title label is the 6th and the subtitle is the 7th subview of the callout:
if (myAnnotationView.subviews.count > 0)
((UILabel*)[((UIView*)[myAnnotationView.subviews objectAtIndex:0]).subviews objectAtIndex:7]).text = #"Some example";

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