UIKit框架-高级控件:6.UIPickerView与UIImageView结合使用

在前面, 我们用UIPickerView, UILabel, UITextFeild做了一个日期选择的小Demo, 现在让我们继续来看看UIPickerView和其他UI控件的结合.

1.定义全局变量

@interface ViewController ()
{
    UILabel *_label;
    UIImageView *_imageView;
}
@end

2.在.h文件里遵守代理方法

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController <UIImagePickerControllerDelegate, UINavigationControllerDelegate>
@end

3.添加UILabel

- (void)myLabel
{
    _label = [[UILabel alloc] initWithFrame:CGRectMake(20, 30, 45, 20)];
    [_label setBackgroundColor:[UIColor greenColor]];
    [_label setText:@"头像: "];
    [self.view addSubview:_label];
}

4.添加UIImageView

#pragma mark - UIImageView方法
- (void)myImageView
{
    CGFloat imageViewX = _label.frame.size.width + 30;
    _imageView = [[UIImageView alloc] initWithFrame:CGRectMake(imageViewX, 28, 200, 200)];
    [_imageView setBackgroundColor:[UIColor redColor]];
    [self.view addSubview:_imageView];
}

5.添加UIButton

- (void)myButton
{
    CGFloat buttonX = _label.frame.size.width + 30;
    CGFloat buutonY = _imageView.frame.size.height + 40;
    CGFloat buttonW = _imageView.frame.size.width;
    
    UIButton *button = [UIButton buttonWithType:UIButtonTypeSystem];
    [button setFrame:CGRectMake(buttonX, buutonY, buttonW, 30)];
    [button setTitle:@"选择头像按钮" forState:UIControlStateNormal];
    
    [button setBackgroundColor:[UIColor blackColor]];
    [button addTarget:self action:@selector(selectPhoto) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button];
}

6.添加UIButton的监听方法

- (void)selectPhoto
{
    UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
    [imagePickerController setSourceType:UIImagePickerControllerSourceTypePhotoLibrary];
    [imagePickerController setAllowsEditing:YES];
    [imagePickerController setDelegate:self];
    [self presentViewController:imagePickerController animated:YES completion:nil];
}

7.添加ImagePikerController的代理方法

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    NSLog(@"%@", info);
    UIImage *image = info[@"UIImagePickerControllerEditedImage"];
    [_imageView setImage:image];
    [self dismissViewControllerAnimated:YES completion:nil];
}

PS: UIImagePickerControllerEditedImage这个东西是在info里面打印出来的, 而info就是一个Dictionary, 里面有几个键值对, 例子中选择的是可以截取一部分图像添加到UIImageView中.

8.在viewDidLoad中实现所有的方法

- (void)viewDidLoad {
    [super viewDidLoad];
    [self myLabel];
    [self myImageView];
    [self myButton];
}

最终的效果是:

  

 

 

PS: 腾讯QQ里面选择头像也是这么做的.

好了, 这次我们就讲到这里, 下次我们继续~~~