【iPhone】UIImagePickerController 查看图片，视频，录像

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

<UIImagePickerControllerDelegate,UINavigationControllerDelegate>

选择、显示图片或视频，主要注意几个属性的设置

一：UI 显示样式，显示的格式确定

1：

@property(nonatomic) UIImagePickerControllerSourceType sourceType

enum {

UIImagePickerControllerSourceTypePhotoLibrary,

UIImagePickerControllerSourceTypeCamera,

UIImagePickerControllerSourceTypeSavedPhotosAlbum

};

typedef NSUInteger UIImagePickerControllerSourceType;

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:  

@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

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:  

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 = [[UIImagePickerControlleralloc] init];

        if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]){

     ipc.sourceType =  UIImagePickerControllerSourceTypePhotoLibrary;

      ipc.mediaTypes =[UIImagePickerControlleravailableMediaTypesForSourceType:ipc.sourceType];  

        } 

ipc.delegate = self;

ipc.allowsImageEditing = NO;

[selfpresentModalViewController: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:[selffindUniqueSavePath] atomically:YES];

    SETIMAGE(image);

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

}

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

NSURL *videoURL = [info objectForKey:UIImagePickerControllerMediaURL];

NSLog(@"found a video");

        NSData *webData = [NSDatadataWithContentsOfURL:videoURL];

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

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

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

//NSLog(videoURL);

}

[picker dismissModalViewControllerAnimated:YES];

}

SDK 3.1重要更新：

In iPhone OS 3.1 and later, you can assign a custom view to the property and use that view to present additional information or manage the interactions between the camera interface and your code.