Create views based on amount of items in an array - ios

Question

I am working on a quiz application, where I get the quiz items from an api. Right now, each question consist of an image and 4 possible answers. Currently, I have two views attached to my view controller(front view and back view), and they change to one and other, when an answer button is clicked(I am only displaying the first two questions this way).
Right now with each api call, I get 7 items(meaning 1 image and 4 answers for each item). But amount of questions can change anytime, so I am trying to implement a way to automate the view creation process.
Based on what I searched this is what I was able to come up with it:
QuizMainViewController.h
#import <UIKit/UIKit.h>
#interface QuizMainViewController: UIViewController <UIScrollViewDelegate>
#property (nonatomic,retain)NSArray *results;
#property (nonatomic,assign)NSUInteger currentItemIndex;
#property(nonatomic,assign)NSUInteger numberOfItemsIntheResultsArray;
QuizMainViewController.m
#import "QuizMainViewController.m"
#import "AppDelegate.h"
#import "Base64.h"
#import "Item.h"
#import "SVProgressHUD.h"
#import <UIKit/UIKit.h>
#interface QuizMainViewController ()
#property(nonatomic,strong)IBOutlet UIView *frontView;
#property (nonatomic,strong)IBOutlet UIView *BackView;
//first view outlets
#property (strong, nonatomic) IBOutlet UIImageView *frontViewImage;
#property (nonatomic,weak) IBOutlet UIButton *frontViewAnswer1;
#property (nonatomic,weak) IBOutlet UIButton *frontViewAnswer2;
#property (nonatomic,weak)IBOutlet UIButton *frontViewAnswer3;
#property (nonatomic,weak) IBOutlet UIButton *frontViewAnswer4;
//second view outlets
#property (strong, nonatomic) IBOutlet UIImageView *backViewImage;
#property(nonatomic,weak) IBOutlet UIButton *backViewAnswer1;
#property(nonatomic,weak) IBOutlet UIButton *backViewAnswer2;
#property(nonatomic,weak) IBOutlet UIButton *backViewAnswer3;
#property(nonatomic,weak) IBOutlet UIButton *backViewAnswer4;
#implementation QuizMainViewController
//the method that I am making the api call
-(void)loadQuizObjectsMethod
{
// this is the part I make the call and try to set the views based on if the items.count is odd or even.
operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *req, NSHTTPURLResponse *response, id jsonObject)
{
NSArray *array = [jsonObject objectForKey:#"Items"];
NSLog(#"Item array: %#",array);
NSMutableArray *tempArray = [[NSMutableArray alloc] init];
for (NSDictionary * itemDict in array) {
Item *myResponseItems = [[Item alloc] initWithDictionary:itemDict];
[tempArray addObject:myResponseItems];
}
_results = tempArray;
//this is where I need help with
Item *item = [_results objectAtIndex:_numberOfItemsIntheResultsArray];
for (_numberOfItemsIntheResultsArray in _results) {
if (_currentItemIndex %2 == 0) {
_currentItemIndex
//implement the front view
}else if (_currentItemIndex %2 == 1)
{
//implement the back view
}
}
I appreciate your help.

Answer 1

You need to use UIPageViewController class in such situations. First create a class called QuestionViewController as follows
QuestionViewController.h
#property (strong, nonatomic) IBOutlet UIImageView *image;
#property (nonatomic,weak) IBOutlet UIButton *answer1;
#property (nonatomic,weak) IBOutlet UIButton *answer2;
#property (nonatomic,weak)IBOutlet UIButton *answer3;
#property (nonatomic,weak) IBOutlet UIButton *answer4;
#property (strong, nonatomic) Item *questionDetailsFromJSON;
QuestionViewController.m
-(void)viewDidLoad
{
self.image = self.questionDetailsFromJSON.image
//set all remaining outlets similar to this.
}
In the storyboard or xib embed a UIPageViewController in your QuizMainViewController using aUIContainer. Set QuizMainViewController as the delegate to the page view controller.
Change your QuizMainViewController.m as follows
#interface QuizMainViewController ()
#property(nonatomic,weak)IBOutlet UIPageViewController *pvc;
#implementation QuizMainViewController
//Implement all of the other methods
- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController
{
int index = [self.results indexOfObject:[(QuestionViewController *)viewController question]];
index++;
QuestionViewController *qvc = nil;
if(index<self.results.count)
{
qvc = //Instantiate from story board or xib
qvc.questionDetailsFromJSON = [self.results objectAtIndex:index];
}
return qvc;
}
- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
int index = [self.results indexOfObject:[(QuestionViewController *)viewController question]];
index--;
QuestionViewController *qvc = nil;
if(index>=0)
{
qvc = //Instantiate from story board or xib
qvc.questionDetailsFromJSON = [self.results objectAtIndex:index];
}
return qvc;
}
Follow this tutorial for further details.

Answer 2

The other poster's suggestion about using a page view controller is good. That would let you manage the pages with questions on them in a nice clean way.
As to your question of a variable number of fields on the form:
The simplest thing to do is to build your form for the maximum number of questions. Then, when you display it, hide those buttons/images that are not used for the current question.
You can create outlets for each button/image and then manipulate them directly, or you can assign tag numbers to them. If you use tag numbers it's a little easier to write code that shows the correct number of answer buttons.
Alternatively you could write code that creates and adds the buttons to the view controller hierarchy on the fly, but creating view objects directly in code is a little more work than doing it with IB. That's more than I can explain in detail in a forum post. For that, you should probably search for a tutorial on creating buttons through code rather than IB. It end up being like 4 or 5 lines of code per button.
A rough outline of the steps: You have to create a button using initWithFrame or the UIButton buttonWithType class method. You have to add a target/action to the button. You have to set it's title. You have to set it's frame, you have to save a pointer to it in an instance variable or an array, and you have to add it as a subview to your view controller's content view.