iOS学习：调用相机，选择图片上传，带预览功能

摘要  iOS调用相机，iOS调用相册，保存至应用程序沙盒，高保真压缩图片，并有点击放大预览，再次点击缩回至原大小，带动画效果，附源码下载地址。 Xcode版本4.5.1 类库ios6.0

IOS调用相机  图片预览  图片上传  压缩图片  模拟器添加图片

目录[-]

判断是否支持相机，跳转到相机或相册界面

七、保存图片 高保真压缩图片方法

八、实现点击图片预览功能，滑动放大缩小，带动画

ps：模拟器添加图片

源码下载地址： 

一、新建工程

二、拖控件，创建映射

三、在.h中加入delegate

1 @interface ViewController : UIViewController<UIActionSheetDelegate,UIImagePickerControllerDelegate,UINavigationControllerDelegate>

四、实现按钮事件

01 -(IBAction)chooseImage:(id)sender {
02
03     UIActionSheet *sheet;
04 <p>
05 // 判断是否支持相机
06 </p>
07 if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
08
09        {
10            sheet  = [[UIActionSheet alloc] initWithTitle:@"选择" delegate:self cancelButtonTitle:nil destructiveButtonTitle:@"取消" otherButtonTitles:@"拍照",@"从相册选择", nil];
11
12        }
13
14     else {
15
16         sheet = [[UIActionSheet alloc] initWithTitle:@"选择" delegate:self cancelButtonTitle:nil destructiveButtonTitle:@"取消" otherButtonTitles:@"从相册选择", nil];
17
18     }
19
20     sheet.tag = 255;
21
22     [sheet showInView:self.view];
23
24 }

五、实现actionSheet delegate事件

判断是否支持相机，跳转到相机或相册界面

01 -(void) actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
02 {
03     if (actionSheet.tag == 255) {
04
05         NSUInteger sourceType = 0;
06
07         // 判断是否支持相机
08         if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
09
10             switch (buttonIndex) {
11                 case 0:
12                     // 取消
13                     return;
14                 case 1:
15                     // 相机
16                     sourceType = UIImagePickerControllerSourceTypeCamera;
17                     break;
18
19                 case 2:
20                     // 相册
21                     sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
22                     break;
23             }
24         }
25         else {
26             if (buttonIndex == 0) {
27
28                 return;
29             } else {
30                 sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
31             }
32         }
33 <p>
34 // 跳转到相机或相册页面
35 </p>
36 UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
37
38         imagePickerController.delegate = self;
39
40         imagePickerController.allowsEditing = YES;
41
42         imagePickerController.sourceType = sourceType;
43
44         [self presentViewController:imagePickerController animated:YES completion:^{}];
45
46         [imagePickerController release];
47     }
48 }

六、实现ImagePicker delegate 事件

01 #pragma mark - image picker delegte
02 - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
03 {
04     [picker dismissViewControllerAnimated:YES completion:^{}];
05
06     UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage];
07     /* 此处info 有六个值
08      * UIImagePickerControllerMediaType; // an NSString UTTypeImage)
09      * UIImagePickerControllerOriginalImage;  // a UIImage 原始图片
10      * UIImagePickerControllerEditedImage;    // a UIImage 裁剪后图片
11      * UIImagePickerControllerCropRect;       // an NSValue (CGRect)
12      * UIImagePickerControllerMediaURL;       // an NSURL
13      * UIImagePickerControllerReferenceURL    // an NSURL that references an asset in the AssetsLibrary framework
14      * UIImagePickerControllerMediaMetadata    // an NSDictionary containing metadata from a captured photo
15      */
16     // 保存图片至本地，方法见下文
17     [self saveImage:image withName:@"currentImage.png"];
18
19     NSString *fullPath = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:@"currentImage.png"];
20
21     UIImage *savedImage = [[UIImage alloc] initWithContentsOfFile:fullPath];
22
23     isFullScreen = NO;
24     [self.imageView setImage:savedImage];
25
26     self.imageView.tag = 100;
27
28 }
29 - (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
30 {
31     [self dismissViewControllerAnimated:YES completion:^{}];
32 }

七、保存图片
高保真压缩图片方法

NSData * UIImageJPEGRepresentation ( UIImage *image, CGFloat compressionQuality
)

此方法可将图片压缩，但是图片质量基本不变，第二个参数即图片质量参数。 

01 #pragma mark - 保存图片至沙盒
02 - (void) saveImage:(UIImage *)currentImage withName:(NSString *)imageName
03 {
04
05     NSData *imageData = UIImageJPEGRepresentation(currentImage, 0.5);
06     // 获取沙盒目录
07
08     NSString *fullPath = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:imageName];
09     // 将图片写入文件
10
11     [imageData writeToFile:fullPath atomically:NO];
12 }

八、实现点击图片预览功能，滑动放大缩小，带动画

01 -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
02 {
03
04     isFullScreen = !isFullScreen;
05     UITouch *touch = [touches anyObject];
06
07     CGPoint touchPoint = [touch locationInView:self.view];
08
09     CGPoint imagePoint = self.imageView.frame.origin;
10     //touchPoint.x ，touchPoint.y 就是触点的坐标
11
12     // 触点在imageView内，点击imageView时 放大,再次点击时缩小
13     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)
14     {
15         // 设置图片放大动画
16         [UIView beginAnimations:nil context:nil];
17         // 动画时间
18         [UIView setAnimationDuration:1];
19
20         if (isFullScreen) {
21             // 放大尺寸
22
23             self.imageView.frame = CGRectMake(0, 0, 320, 480);
24         }
25         else {
26             // 缩小尺寸
27             self.imageView.frame = CGRectMake(50, 65, 90, 115);
28         }
29
30         // commit动画
31         [UIView commitAnimations];
32
33     }
34
35 }

九、上传图片，使用ASIhttpRequest类库实现，由于本文重点不是网络请求，故不对ASIHttpRequest详细讲述，只贴出部分代码

01 ASIFormDataRequest *requestReport  = [[ASIFormDataRequest alloc] initWithURL:服务器地址];
02
03 NSString *Path = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:@"currentImage.png"];
04
05 [requestReport setFile:Path forKey:@"picturepath"];
06
07 [requestReport buildPostBody];
08
09 requestReport.delegate = self;
10
11 [requestReport startAsynchronous];

效果图如下：

          ->

      

      

ps：模拟器添加图片

1.模拟器无法调用相机；

2.模拟器添加图片方法：将图片拖至模拟器主屏，会由模拟器safari打开，长按可保存至模拟器相册，即可进行模拟器调试了。

3.关于调用相机，是系统自带的，不知道如何修改英文标题为中文，如cancel换为取消等，望知道的大虾们不吝告知，万分感谢

源码下载地址： 

115网盘礼包接收地址：  http://115.com/lb/5lbqrhfl 
115网盘礼包码：5lbqrhfl

code4App下载地址：http://code4app.com/ios/51a8023c6803fa2b06000000

原始地址：http://my.oschina.net/joanfen/blog/134677