Objective-C Learning Notes - UISegmentControl 2

选中时修改 segment 图片:

#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController
@synthesize myImages,myLabels;
- (void)viewDidLoad {
    [super viewDidLoad];
    
    UIImage *image1 = [UIImage imageNamed:@"0.jpg"];
    
    UIImage *image2 = [UIImage imageNamed:@"1.png"];
    
    UIImage *image3 = [UIImage imageNamed:@"2.png"];
    
    myImages = [[NSArray alloc]initWithObjects:image1,image2,image3, nil];
    
    myLabels = [[NSArray alloc]initWithObjects:@"Lion",@"Elephant",@"Dog", nil];
    
    UISegmentedControl *mySegmentControl = [[UISegmentedControl alloc]initWithItems:myLabels];
    
    mySegmentControl.frame = CGRectMake(10, 50, 300, 300);
    
    [mySegmentControl addTarget:self action:@selector(segmentDidChange:) forControlEvents:UIControlEventValueChanged];
    
    [self.view addSubview:mySegmentControl];
    
    // Do any additional setup after loading the view, typically from a nib.
}
- (void) segmentDidChange:(id)sender{
    if ([sender isKindOfClass:[UISegmentedControl class]]){
        UISegmentedControl *segmentControl = sender;
        for (int i=0; i<segmentControl.numberOfSegments; ++i) {
            if (i == segmentControl.selectedSegmentIndex){
                [segmentControl setImage:[myImages objectAtIndex:i] forSegmentAtIndex:i];
            }else{
                [segmentControl setTitle:[myLabels objectAtIndex:i] forSegmentAtIndex:i];
            }
        }
    }
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
@end

#import <UIKit/UIKit.h>
@interface ViewController : UIViewController
@property (strong,nonatomic) NSArray *myLabels,*myImages;
@end

不知道为什么图片显示不出来......