iOS调用系统相机，访问系统相册功能实现

        我们在做应用过程中，难免会遇到要设置用户头像这样的功能，我这里总结了一个调用系统相机，相册的功能实现，写出来与大家分享，如有不足还请指正：

1.我们在调用这个功能的时候，一般都有个用来填充图片的ImageView和点击ImageView触发此方法的事件，这里我就写个ImageView和Button来演示，下面是实现整个功能的代码：

#import "ViewController.h"

#define kWidth [UIScreen mainScreen].bounds.size.width

#define kHeight [UIScreen mainScreen].bounds.size.height

@interface
ViewController ()<UIActionSheetDelegate,UIImagePickerControllerDelegate>

{

    BOOL isFullScreen;

}

@property(nonatomic,strong)UIImageView *imageView;

@end

@implementation ViewController

- (void)viewDidLoad {

    [superviewDidLoad];

    _imageView = [[UIImageViewalloc]initWithFrame:CGRectMake(100,100,
200,
200)];

    _imageView.backgroundColor = [UIColorgrayColor];

    [self.viewaddSubview:_imageView];

    

    UIButton *chooseBtn = [UIButtonbuttonWithType:UIButtonTypeCustom];

    chooseBtn.frame =
CGRectMake(100,
30, 100,
40);

    [chooseBtn addTarget:selfaction:@selector(chooseImage:)forControlEvents:UIControlEventTouchUpInside];

    [chooseBtn setBackgroundColor:[UIColorbrownColor]];

    [chooseBtn setTitle:@"选择照片"forState:UIControlStateNormal];

    [self.viewaddSubview:chooseBtn];

}

#pragma mark -
保存图片至沙盒

- (void) saveImage:(UIImage *)currentImage withName:(NSString *)imageName

{

    

    NSData *imageData =
UIImageJPEGRepresentation(currentImage,
0.5);

    //
获取沙盒目录

    NSString *fullPath = [[NSHomeDirectory()stringByAppendingPathComponent:@"Documents"]stringByAppendingPathComponent:imageName];

    

    //
将图片写入文件

    [imageData writeToFile:fullPath
atomically:NO];

}

#pragma mark - image picker delegte

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

{

    [picker dismissViewControllerAnimated:YEScompletion:^{}];

    

    UIImage *image = [infoobjectForKey:UIImagePickerControllerOriginalImage];

    

    [selfsaveImage:imagewithName:@"currentImage.png"];

    

    NSString *fullPath = [[NSHomeDirectory()stringByAppendingPathComponent:@"Documents"]stringByAppendingPathComponent:@"currentImage.png"];

    

    UIImage *savedImage = [[UIImagealloc]
initWithContentsOfFile:fullPath];

    

    isFullScreen =NO;

    [self.imageViewsetImage:savedImage];

    

    self.imageView.tag =100;

    

}

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker

{

    [selfdismissViewControllerAnimated:YEScompletion:^{}];

}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

    

    isFullScreen = !isFullScreen;

    UITouch *touch = [touches
anyObject];

    

    CGPoint touchPoint = [touch
locationInView:self.view];

    

    CGPoint imagePoint =
self.imageView.frame.origin;

    //touchPoint.x
，touchPoint.y
就是触点的坐标

    

    //
触点在imageView内，点击imageView时放大,再次点击时缩小

    if(imagePoint.x <= touchPoint.x && imagePoint.x +self.imageView.frame.size.width
>=touchPoint.x && imagePoint.y <=  touchPoint.y && imagePoint.y+self.imageView.frame.size.height
>= touchPoint.y)

    {

        //
设置图片放大动画

        [UIViewbeginAnimations:nilcontext:nil];

        // 动画时间

        [UIViewsetAnimationDuration:1];

        

        if (isFullScreen) {

            // 放大尺寸

            

            self.imageView.frame =CGRectMake(0,0,
kWidth, kHeight);

        }

        else {

            // 缩小尺寸

            self.imageView.frame =CGRectMake(100,100,
200, 200);

        }

          // commit动画

        [UIViewcommitAnimations];

        

    }

    

}

#pragma mark - actionsheet delegate

-(void) actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex

{

    if (actionSheet.tag ==255) {

        

        NSUInteger sourceType =
0;

        

        //
判断是否支持相机

        if([UIImagePickerControllerisSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
{

            

            switch (buttonIndex) {

                case
0:

                    //
取消

                    return;

                case
1:

                    //
相机

                    sourceType =
UIImagePickerControllerSourceTypeCamera;

                    break;

                    

                case
2:

                    //
相册

                    sourceType =
UIImagePickerControllerSourceTypePhotoLibrary;

                    break;

            }

        }

        else {

            if (buttonIndex ==
0) {

                

                return;

            } else {

                sourceType =
UIImagePickerControllerSourceTypeSavedPhotosAlbum;

            }

        }

        //
跳转到相机或相册页面

        UIImagePickerController *imagePickerController = [[UIImagePickerControlleralloc]
init];

        

        imagePickerController.delegate =
self;

        

        imagePickerController.allowsEditing =
YES;

        

        imagePickerController.sourceType = sourceType;

        

        [self
presentViewController:imagePickerControlleranimated:YEScompletion:^{}];

        

    }

}

- (void)chooseImage:(UIButton *)btn {

    

    UIActionSheet *sheet;

   
// 判断是否支持相机

    if([UIImagePickerControllerisSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])

    {

        sheet  = [[UIActionSheetalloc]
initWithTitle:@"选择"delegate:selfcancelButtonTitle:nildestructiveButtonTitle:@"取消"otherButtonTitles:@"拍照",@"从相册选择",nil];

    }

    else {

        sheet = [[UIActionSheetalloc]
initWithTitle:@"选择"delegate:selfcancelButtonTitle:nildestructiveButtonTitle:@"取消"otherButtonTitles:@"从相册选择",nil];

    }

    sheet.tag =
255;

    [sheet showInView:self.view];

}

@end

2.奇怪的是我们不签代理，功能也能实现，为了保险起见，还是签订代理；到此，要实现的基本功能已经完全展示出来了，我们再根据自己项目的需求来改动就可以了。

3.希望对大家有所帮助。