Can't assign text to UITextView

Question

I'm trying to make an iOS application where the user opens the app, and simply taps on a cell to view information on a certain topic. I have everything set up accordingly I think, however when I run the app and tap on a cell, my .txt file is not showing up in the textView. What am I doing wrong?

My Xcode project

.m file of detail view controller

@interface DetailViewController ()

@end

@implementation DetailViewController
@synthesize detailText = _detailText;

 (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil

{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {

    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

}


-(void)viewDidAppear:(BOOL)animated{

    self.textView.text = _detailText;
}

.h file of detail view controller

 @interface DetailViewController : UIViewController

    @property (nonatomic, retain) UITextView *detailText;
    @property (strong, nonatomic) IBOutlet UITextView *textView;

    @end

*.m file of tableviewcontroller*

@implementation TableViewController
- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        // Custom initialization
    }
    return self;
}



 - (void)viewDidLoad
{
   self.tableViewText = [[UITextView alloc] init];
    [super viewDidLoad];

    self.titleObjectsArray = @[@"D 1.1",
                               @"D 1.2",
                               @"D 1.3",
                               @"D 1.4",];

    self.subtitleObjectsArray = @[@"Pharmaceutical Products",
                               @"Pharmaceutical Products",
                               @"Pharmaceutical Products",
                               @"Pharmaceutical Products",];

    self.textObjectsArray = @[@"D 1.1.txt",
                              @"D 1.2.txt",
                              @"D 1.3.txt",
                              @"D 1.4.txt",];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];

}



- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{


    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{


    return [self.titleObjectsArray count];;
}
 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{

    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    cell.textLabel.text = [self.titleObjectsArray objectAtIndex: indexPath.row];
    cell.detailTextLabel.text = [self.subtitleObjectsArray objectAtIndex:indexPath.row];



        return cell;

}

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
    self.tableViewText.text = [self.textObjectsArray objectAtIndex:indexPath.row];
    [self performSegueWithIdentifier:@"detail" sender:self];

}

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
    if ([segue.identifier isEqualToString:@"detail"]) {
        DetailViewController *detailVC = (DetailViewController *)segue.destinationViewController;
        detailVC.detailText = self.tableViewText;
    }
}

Answer 1

In various places throughout your project you're missing an important step you must take when using objects. Add the following code to the viewDidLoad() function of your TableView.

  self.tableViewText = [[UITextView alloc] init];

This should point in the right direction to begin fixing your errors.

Think about when and why you need to init an object, think about what the init method should do in your classes, and also think about what you are doing in your various assignment statements. Ask yourself, "do I want to assign entire an entire object to something, or do I want to assign just one property of the object?"

This is an example in DetailView of where you're doing assignment wrong:

-(void)viewDidAppear:(BOOL)animated{

    self.textView.text = _detailText;
 }

Further, think about what objects would be best suited for what you are trying to accomplish. Are there places where there may be an object better suited for storing text than UITextView?

I think you need to revisit some of the beginning chapters of whichever resource you used to learn objective-c. You are missing some basic concepts that you must understand in order to get anything accomplished.