progress bar code in vb net 2010 1. Information for creating the data model in Objective-C

Create Data Matrix ECC200 in Objective-C 1. Information for creating the data model

client client client client client client client client consultant consultant consultant consultant consultant consultant journalEntry journalEntry journalEntry journalEntry journalEntry journalEntry journalEntry journalEntry taskType taskType taskType

clientContactEmailAddress clientContactFirstName clientContactLastName clientContactMobilePhone clientContactOfficePhone clientName clientStreetAddress entriesForClient consultantFirstName consultantLastName consultantMobilePhone consultantOfficePhone consultantStreetAddress entriesForConsultant clientForEntry consultantForEntry entryCharge entryContent entryDate entryInvoiced entryName taskTypeForEntry entriesForTaskType taskTypeDescription taskTypeName

Attribute Attribute Attribute Attribute Attribute Attribute Attribute Relationship Attribute Attribute Attribute Attribute Attribute Relationship Relationship Relationship Attribute Attribute Attribute Attribute Attribute Relationship Relationship Attribute Attribute

String String String String String String String journalEntry (To-Many) String String String String String journalEntry (To-Many) client consultant Float Binary data Date Boolean String taskType journalEntry (To-Many) String String

Once you have built the data model, save it and close the window (if it is in a separate window). That s all you need to do in Xcode for now time to move to Interface Builder to create the user interface components.

When you create a Core Data Cocoa application you have a choice of three different formats for storage: SQLite, XML or binary. This is configured in the DailyJournal_AppDelegate.m file, in the method called persistentStoreCoordinator. In Listing 9 1 you will see the significant code fragment:

Listing 9 1. Setting the Storage Options for the DailyJournal Application url = [NSURL fileURLWithPath: [applicationSupportFolder stringByAppendingPathComponent: @"storedata"]]; persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel: [self managedObjectModel]]; if (![persistentStoreCoordinator addPersistentStoreWithType:NSXMLStoreType configuration:nil URL:url options:nil error:&error]){ [[NSApplication sharedApplication] presentError:error]; }

The first bold section shows the filename used to store your data. You can actually give this any name you like: a.b, for example. The second bold section is where you choose the storage format. Your choices are NSXMLStoreType (the default, as an XML file), NSSQLiteStoreType (for a SQLite database), or NSBinaryStoreType (for the more traditional binary data format used for Mac OS X data stores before the days of Core Data). Generally speaking, the XML format is the best option to use during development, as it is easy to make changes to your data model and also to inspect the data file using external tools such as XML editors. When you go into production you may want to change over to one of the other storage formats SQLite is more scalable than XML if your database is likely to grow.

The main user interface for this application is going to display a list and detail view of journal entries. So there will be a list of the entries probably by name. For each entry selected, the detail part of the interface will show the other information. We will want a way to add and remove entries, too. Start by giving the main user interface window a more useful name (it s just called Window in the Document window) I usually begin the names of windows with a lowercase w, so I called this one wJournalEntries. It is not actually necessary to rename objects in the Document window, but you will be creating several windows and controllers during this project, and it is a good practice to give meaningful names to such objects.

Now open the window and drag a Core Data Entity object into it from the Library. This brings up the New Core Data Entity Interface assistant. Choose the DailyJournal project, then the DailyJournal_DataModel.xcdatamodel model these are the only options, but in more complex projects you may have a variety of models to choose from. In the last column choose the journalEntry entity, then click Next (see Figure 9 5).

You already know that this is going to show both a list and the detail for each item, so in the next window of the assistant, choose Master/Detail View from the drop-down list. Now let s consider the other options. The first, Search Field, seems like a good choice. There could eventually be many journal entries and so a Spotlight-style mechanism for filtering will be useful. Check that option. You will want to see the detail for each item selected, so check that box. Finally, you also want to be able to add and remove entries, so check that box too. Click Next. In this final step of the assistant you need to specify which property fields from the journalEntry entity should be shown in the user interface. In fact, you want all of these one way or another, so leave them all checked (the default). Click on the Finish button, and you will see something like Figure 9 6. Well, that is seriously ugly isn t it That s the problem with auto-generated interfaces of course they are intelligent, but really not that intelligent. What you have here is a collection of controls that have the appropriate connections to the controller, but the layout leaves much to be desired. Also, you will see that the process of generating the controls doesn t always get it right. Look at the control that the assistant has generated for the Entry Content. It s an Image Well control since you specified that the attribute needed to contain binary data, the assistant (reasonably, perhaps, but incorrectly) concluded that you wanted an Image View control. You ll need to change that, since you actually want to store text and images here (a Text View seems more appropriate). Given the amount of change that you will need to make here it s arguable that it would have been better to create the controls from scratch. However, the auto-generated interface has its place, so let s work with it and see what we can do with it.