#import <UIKit/UIKit.h>

@interface PickerViewController : UIViewController <UIPickerViewDelegate, UIPickerViewDataSource>

@end

@interface PickerViewController ()

{
	NSArray *letterArray;
}

@property (strong, nonatomic) UIView *viewForMainPicker;

@end

@implementation PickerViewController

- (void)viewDidLoad {
	[super viewDidLoad];
	self.tabBarController.tabBar.hidden = YES;
	//[self.view setBackgroundColor:[UIColor clearColor]];
	[self.view setBackgroundColor:[UIColor systemYellowColor]];
	
	letterArray = @[@"",@"A",@"B",@"C",@"D"];
	
	UIBarButtonItem *pBtn = [[UIBarButtonItem alloc] initWithTitle:@"picker"
															 style:UIBarButtonItemStylePlain
															target:self
															action:@selector(launchPicker:)];
	self.navigationItem.rightBarButtonItem = pBtn;
}

- (void)launchPicker:(id)sender {
	
	// let's use auto-layout / constraints instead of explicit frames
	//self.viewForMainPicker = [[UIView alloc]initWithFrame:CGRectMake(0, 400, [[UIScreen mainScreen] bounds].size.width, 220)];
	//UIToolbar *toolBar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, [[UIScreen mainScreen] bounds].size.width, 44)];
	//UIPickerView *mainPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 0, [[UIScreen mainScreen] bounds].size.width, 220)];
	
	self.viewForMainPicker = [UIView new];
	UIToolbar *toolBar = [UIToolbar new];
	UIPickerView *mainPicker = [UIPickerView new];
	
	UIFont *arrowfont = [UIFont boldSystemFontOfSize:40];
	UIFont *titlefont = [UIFont boldSystemFontOfSize:28];
	UIBarButtonItem *doneBtn = [[UIBarButtonItem alloc] initWithTitle:@"→"
																style:UIBarButtonItemStylePlain
															   target:self
															   action:@selector(fakeEvent)];
	UIBarButtonItem *title = [[UIBarButtonItem alloc] initWithTitle:@"Select Gender"
															  style:UIBarButtonItemStylePlain
															 target:nil
															 action:nil];
	UIBarButtonItem *flex = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
																		  target:self
																		  action:nil];
	[doneBtn setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:
									 [UIColor colorWithRed:0.933 green:0.122 blue:0.145 alpha:1.00], NSForegroundColorAttributeName,
									 arrowfont, NSFontAttributeName, nil] forState:UIControlStateNormal];
	[title setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:
								   [UIColor colorWithRed:0.933 green:0.122 blue:0.145 alpha:1.00], NSForegroundColorAttributeName,
								   titlefont, NSFontAttributeName, nil] forState:UIControlStateNormal];
	NSArray *btnArray = [[NSArray alloc] initWithObjects:flex,flex,title,flex,doneBtn,nil];
	
	mainPicker.delegate = self;
	mainPicker.dataSource = self;
	
	[toolBar setItems:btnArray];
	[_viewForMainPicker addSubview:mainPicker];
	[_viewForMainPicker addSubview:toolBar];
	
	[self.view addSubview:_viewForMainPicker];
	
	_viewForMainPicker.translatesAutoresizingMaskIntoConstraints = NO;
	mainPicker.translatesAutoresizingMaskIntoConstraints = NO;
	toolBar.translatesAutoresizingMaskIntoConstraints = NO;
	
	UILayoutGuide *g = self.view.safeAreaLayoutGuide;
	
	[NSLayoutConstraint activateConstraints:@[
		
		[_viewForMainPicker.topAnchor constraintEqualToAnchor:g.topAnchor constant:400.0],
		[_viewForMainPicker.leadingAnchor constraintEqualToAnchor:g.leadingAnchor constant:0.0],
		[_viewForMainPicker.trailingAnchor constraintEqualToAnchor:g.trailingAnchor constant:0.0],
		[_viewForMainPicker.heightAnchor constraintEqualToConstant:220.0],

		[toolBar.topAnchor constraintEqualToAnchor:_viewForMainPicker.topAnchor constant:0.0],
		[toolBar.leadingAnchor constraintEqualToAnchor:_viewForMainPicker.leadingAnchor constant:0.0],
		[toolBar.trailingAnchor constraintEqualToAnchor:_viewForMainPicker.trailingAnchor constant:0.0],
		[toolBar.heightAnchor constraintEqualToConstant:44.0],

		[mainPicker.topAnchor constraintEqualToAnchor:toolBar.bottomAnchor constant:0.0],
		[mainPicker.leadingAnchor constraintEqualToAnchor:_viewForMainPicker.leadingAnchor constant:0.0],
		[mainPicker.trailingAnchor constraintEqualToAnchor:_viewForMainPicker.trailingAnchor constant:0.0],
		[mainPicker.bottomAnchor constraintEqualToAnchor:_viewForMainPicker.bottomAnchor constant:0.0],

	]];
	
	self.viewForMainPicker.backgroundColor = [UIColor whiteColor];
	
}

- (void)fakeEvent {
	NSLog(@"selected");
}

- (NSInteger)numberOfComponentsInPickerView:(nonnull UIPickerView *)pickerView {
	return 1;
}

- (NSInteger)pickerView:(nonnull UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
	return letterArray.count;
}

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
	return letterArray[row];
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
	NSString *newString = [NSString stringWithFormat:@"%@", letterArray[row]];
	NSLog(@"passing: %@",newString);
}

@end