UIImagePickerController

【iPhone】UIImagePickerController 查看图片，视频，录像

UIImagePickerController

－－ the only sanctioned way to get videos/movies or images/pictures on supported devices

<UIImagePickerControllerDelegate,UINavigationControllerDelegate>

用UIImagePickerController选择、显示图片或视频，主要注意UIImagePickerController几个属性的设置

一：UI 显示样式，显示的格式确定

1：sourceType

@property(nonatomic) UIImagePickerControllerSourceType sourceType

enum {

UIImagePickerControllerSourceTypePhotoLibrary,

UIImagePickerControllerSourceTypeCamera,

UIImagePickerControllerSourceTypeSavedPhotosAlbum

};

typedef NSUInteger UIImagePickerControllerSourceType;

sourceType用来确定用户界面显示的样式：

共三种格式（模拟器上的效果图）

UIImagePickerControllerSourceTypePhotoLibrary,

UIImagePickerControllerSourceTypeCamera,





UIImagePickerControllerSourceTypeSavedPhotosAlbum



为了区分是否支持视频格式，一般要用到下面这个函数，以便确定mediaTypes。

+ (BOOL)isSourceTypeAvailable:(UIImagePickerControllerSourceType)sourceType

2: mediaTypes

@property(nonatomic,copy) NSArray *mediaTypes

mediaTypes用来确定再picker里显示那些类型的多媒体文件，图片？视频？

+ (NSArray *)availableMediaTypesForSourceType:(UIImagePickerControllerSourceType)sourceType

二：选取动作处理

UIImagePickerControllerDelegate


通过代理来完成用户在选中图片，或者choose视频时的处理方式：

共有三个可选的代理方法

– imagePickerController:didFinishPickingMediaWithInfo:

– imagePickerControllerDidCancel:

– imagePickerController:didFinishPickingImage:editingInfo:
Deprecated in iPhone OS 3.0

- (void)imagePickerController:(UIImagePickerController *)picker
didFinishPickingMediaWithInfo:(NSDictionary *)info

info中包括选取的照片，视频的主要信息

NSString *const UIImagePickerControllerMediaType; 选取的类型
public.image public.movie

NSString *const UIImagePickerControllerOriginalImage; 修改前的UIImage object.

NSString *const UIImagePickerControllerEditedImage; 修改后的UIImage object.

NSString *const UIImagePickerControllerCropRect; 原始图片的尺寸NSValue object containing a CGRect data type

NSString *const UIImagePickerControllerMediaURL; 视频在文件系统中 的 NSURL地址

保存视频主要时通过获取其NSURL 然后转换成NSData

实例代码如下：

- (void) pickImage: (id) sender

{

UIImagePickerController *ipc = [[UIImagePickerController
alloc]
init];

if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]){

ipc.sourceType =
UIImagePickerControllerSourceTypePhotoLibrary;

ipc.mediaTypes =[UIImagePickerController
availableMediaTypesForSourceType:ipc.sourceType];

}

ipc.delegate = self;

ipc.allowsImageEditing =
NO;

[self
presentModalViewController:ipc animated:YES];

}

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

{

NSString *mediaType = [info
objectForKey:UIImagePickerControllerMediaType];

if ([mediaType
isEqualToString:@"public.image"]){

//
UIImage *selectedImage = [info objectForKey:UIImagePickerControllerOriginalImage];

UIImage *image = [info
objectForKey:@"UIImagePickerControllerOriginalImage"];

NSLog(@"found an image");

[UIImageJPEGRepresentation(image,
1.0f)
writeToFile:[self
findUniqueSavePath]
atomically:YES];

SETIMAGE(image);

CFShow([[NSFileManager
defaultManager] directoryContentsAtPath:[NSHomeDirectory()
stringByAppendingString:@"/Documents"]]);

}

else
if ([mediaType isEqualToString:@"public.movie"]){

NSURL *videoURL = [info
objectForKey:UIImagePickerControllerMediaURL];

NSLog(@"found a video");

NSData *webData = [NSData
dataWithContentsOfURL:videoURL];

//NSData *video = [[NSString alloc] initWithContentsOfURL:videoURL];

[webData writeToFile:[self findUniqueMoviePath]
atomically:YES];

CFShow([[NSFileManager
defaultManager] directoryContentsAtPath:[NSHomeDirectory()
stringByAppendingString:@"/Documents"]]);

//
NSLog(videoURL);

}

[picker dismissModalViewControllerAnimated:YES];

}