iOS照片开发之UIImagePickerController
iOS开发中,通常获取照片的方式有三种,1.直接调用摄像头拍照 2.从相册中选择 3.从图库中选择。 通常使用到的类或框架有UIImagePickerController,AssetsLibrary,PhotoKit(iOS8later)。本篇博客主要讲解UIImagePickerController,其他的后续会讲解到。
UIImagePickerController
UIImagePickerController 是系统提供的用来获取图片和视频的类;
用UIImagePickerController 类来获取图片视频,大体分为以下几个步骤:
1. 初始化UIImagePickerController 类;
2. 设置UIImagePickerController 实例的数据来源类型(下面解释);
3. 设置代理;
4. 如果需要做图片修改的话设置allowsEditing =yes。
数据来源类型一共有三种:
enum {
UIImagePickerControllerSourceTypePhotoLibrary ,//来自图库
UIImagePickerControllerSourceTypeCamera ,//来自相机
UIImagePickerControllerSourceTypeSavedPhotosAlbum //来自相册
};
在用这些来源的时候最好检测以下设备是否支持;
if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
{
NSLog(@"支持相机");
}
if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary])
{
NSLog(@"支持图库");
}
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeSavedPhotosAlbum])
{
NSLog(@"支持相片库");
}
调用摄像头来获取资源
- (void)viewDidLoad {
[super viewDidLoad];
picker = [[UIImagePickerController alloc]init];
//获取照片的类型
UIImagePickerControllerSourceType sourcheType = UIImagePickerControllerSourceTypeCamera;
picker.sourceType = sourcheType;
//设置代理
picker.delegate = self;
//是否允许编辑
picker.allowsEditing = YES;
}
上面只是实例了UIImagePickerController及其属性 在需要获取图片的时候需要弹出窗口调用
[self presentViewController:picker animated:YES completion:nil];
代理中一共三个方法 其中一个3.0 已经废弃了,只剩下两个我们需要用的.
1.当用户选取完成后调用:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info;
选取的信息都在info中,info 是一个字典:
字典中的键:
NSString *const UIImagePickerControllerMediaType ;指定用户选择的媒体类型(文章最后进行扩展)
NSString *const UIImagePickerControllerOriginalImage ;原始图片
NSString *const UIImagePickerControllerEditedImage ;修改后的图片
NSString *const UIImagePickerControllerCropRect ;裁剪尺寸
NSString *const UIImagePickerControllerMediaURL ;媒体的URL
NSString *const UIImagePickerControllerReferenceURL ;原件的URL
NSString *const UIImagePickerControllerMediaMetadata;当来数据来源是照相机的时候这个值才有效
1.当用户取消选取时调用:
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker;
UIImagePickerControllerMediaType 包含着KUTTypeImage 和KUTTypeMovie
1.KUTTypeImage 包含:
const CFStringRef kUTTypeImage ;抽象的图片类型
const CFStringRef kUTTypeJPEG ;
const CFStringRef kUTTypeJPEG2000 ;
const CFStringRef kUTTypeTIFF ;
const CFStringRef kUTTypePICT ;
const CFStringRef kUTTypeGIF ;
const CFStringRef kUTTypePNG ;
const CFStringRef kUTTypeQuickTimeImage ;
const CFStringRef kUTTypeAppleICNS
const CFStringRef kUTTypeBMP;
const CFStringRef kUTTypeICO;
2.KUTTypeMovie 包含:
const CFStringRef kUTTypeAudiovisualContent ;抽象的声音视频
const CFStringRef kUTTypeMovie ;抽象的媒体格式(声音和视频)
const CFStringRef kUTTypeVideo ;只有视频没有声音
const CFStringRef kUTTypeAudio ;只有声音没有视频
const CFStringRef kUTTypeQuickTimeMovie ;
const CFStringRef kUTTypeMPEG ;
const CFStringRef kUTTypeMPEG4 ;
const CFStringRef kUTTypeMP3 ;
const CFStringRef kUTTypeMPEG4Audio ;
const CFStringRef kUTTypeAppleProtectedMPEG4Audio;
好了,写了个小Demo,直接上代码了
#import "ViewController.h"
@interface ViewController ()<UIImagePickerControllerDelegate,UINavigationControllerDelegate>
/** imageView */
@property (nonatomic, strong) UIImageView *imageView;
/** imageViewR */
@property (nonatomic, strong) UIImageView *imageViewR;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.imageViewR = [[UIImageView alloc] initWithFrame:CGRectMake((self.view.frame.size.width - 100)/2, 30, 100, 100)];
self.imageViewR.backgroundColor = [UIColor grayColor];
self.imageViewR.layer.cornerRadius = 50;
self.imageViewR.layer.masksToBounds = YES; // 裁剪边
[self.view addSubview:self.imageViewR];
self.imageView = [[UIImageView alloc] initWithFrame:CGRectMake(16, 140, self.view.frame.size.width - 32, self.view.frame.size.width - 32)];
self.imageView.backgroundColor = [UIColor grayColor];
[self.view addSubview:self.imageView];
UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
btn.frame = CGRectMake(16, CGRectGetMaxY(self.imageView.frame) + 20, self.view.frame.size.width - 32, 35);
btn.backgroundColor = [UIColor greenColor];
btn.layer.cornerRadius = 5;
btn.layer.masksToBounds = YES;
[btn setTitle:@"获取图片" forState:UIControlStateNormal];
[btn addTarget:self action:@selector(btnClick:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:btn];
}
- (void)btnClick:(UIButton *)button
{
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"选择照片" message:nil preferredStyle:(UIAlertControllerStyleActionSheet)];
// 判断是否支持相机
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
UIAlertAction *cameraAc = [UIAlertAction actionWithTitle:@"拍照" style:(UIAlertActionStyleDefault) handler:^(UIAlertAction * _Nonnull action) {
UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.delegate = self;
imagePickerController.allowsEditing = YES;
// 设置数据源类型
imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;
[self presentViewController:imagePickerController animated:YES completion:nil];
}];
[alertController addAction:cameraAc];
}
// 图集
UIAlertAction *photoAc = [UIAlertAction actionWithTitle:@"相册" style:(UIAlertActionStyleDefault) handler:^(UIAlertAction * _Nonnull action) {
UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.delegate = self;
imagePickerController.allowsEditing = YES;
imagePickerController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
[self presentViewController:imagePickerController animated:YES completion:nil];
}];
[alertController addAction:photoAc];
// 相片库
UIAlertAction *albumAc = [UIAlertAction actionWithTitle:@"相片库" style:(UIAlertActionStyleDefault) handler:^(UIAlertAction * _Nonnull action) {
UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.delegate = self;
imagePickerController.allowsEditing = YES;
imagePickerController.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;;
[self presentViewController:imagePickerController animated:YES completion:nil];
}];
[alertController addAction:albumAc];
UIAlertAction *cancel = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
}];
[alertController addAction:cancel];
[self presentViewController:alertController animated:YES completion:nil];
}
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
[self dismissViewControllerAnimated:YES completion:nil];
}
// 代理方法,获取图片
// 选取的信息都在info中,info 是一个字典。
/**
// info dictionary keys
UIKIT_EXTERN NSString *const UIImagePickerControllerMediaType __TVOS_PROHIBITED; // an NSString (UTI, i.e. kUTTypeImage)
UIKIT_EXTERN NSString *const UIImagePickerControllerOriginalImage __TVOS_PROHIBITED; // a UIImage
UIKIT_EXTERN NSString *const UIImagePickerControllerEditedImage __TVOS_PROHIBITED; // a UIImage
UIKIT_EXTERN NSString *const UIImagePickerControllerCropRect __TVOS_PROHIBITED; // an NSValue (CGRect)
UIKIT_EXTERN NSString *const UIImagePickerControllerMediaURL __TVOS_PROHIBITED; // an NSURL
UIKIT_EXTERN NSString *const UIImagePickerControllerReferenceURL NS_AVAILABLE_IOS(4_1) __TVOS_PROHIBITED; // an NSURL that references an asset in the AssetsLibrary framework
UIKIT_EXTERN NSString *const UIImagePickerControllerMediaMetadata NS_AVAILABLE_IOS(4_1) __TVOS_PROHIBITED; // an NSDictionary containing metadata from a captured photo
UIKIT_EXTERN NSString *const UIImagePickerControllerLivePhoto NS_AVAILABLE_IOS(9_1) __TVOS_PROHIBITED; // a PHLivePhoto
/
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info
{
[picker dismissViewControllerAnimated:YES completion:nil];
UIImage *image = [info objectForKey:UIImagePickerControllerEditedImage];
// 保存图片到本地沙盒,
[self saveImage:image withName:@"avatar.png"];
NSString *fullPath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent:@"avatar.png"];
UIImage *saveImage = [[UIImage alloc] initWithContentsOfFile:fullPath];
// 设置图片显示
self.imageView.image = saveImage;
self.imageViewR.image = saveImage;
}
- (void)saveImage:(UIImage *)currentImage withName:(NSString *)imageName
{
NSData *imageData = UIImageJPEGRepresentation(currentImage, 1); // 1为不缩放保存,取值为(0~1)
// 获取沙河路径
NSString *fullPath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent:imageName];
// 将照片写入文件
[imageData writeToFile:fullPath atomically:NO];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end