iOS學習：調用相機，選擇圖片上傳，帶預覽功能

2019-11-08 00:26:43

字體：大中小

來源：轉載

供稿：網友

一、新建工程

二、拖控件，創建映射

三、在.h中加入delegate

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

四、實現按鈕事件

-(IBAction)chooseImage:(id)sender { UIActionSheet *sheet;

// 判斷是否支持相機

if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) { sheet = [[UIActionSheet alloc] initWithTitle:@"選擇" delegate:self cancelButtonTitle:nil destructiveButtonTitle:@"取消" otherButtonTitles:@"拍照",@"從相冊選擇", nil]; } else { sheet = [[UIActionSheet alloc] initWithTitle:@"選擇" delegate:self cancelButtonTitle:nil destructiveButtonTitle:@"取消" otherButtonTitles:@"從相冊選擇", nil]; } sheet.tag = 255; [sheet showInView:self.view]; }

五、實現actionSheet delegate事件

判斷是否支持相機，跳轉到相機或相冊界面

-(void) actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex{ if (actionSheet.tag == 255) { NSUInteger sourceType = 0; // 判斷是否支持相機 if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) { switch (buttonIndex) { case 0: // 取消 return; case 1: // 相機 sourceType = UIImagePickerControllerSourceTypeCamera; break; case 2: // 相冊 sourceType = UIImagePickerControllerSourceTypePhotoLibrary; break; } } else { if (buttonIndex == 0) { return; } else { sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum; } }

// 跳轉到相機或相冊頁面

UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init]; imagePickerController.delegate = self; imagePickerController.allowsEditing = YES; imagePickerController.sourceType = sourceType; [self PResentViewController:imagePickerController animated:YES completion:^{}]; [imagePickerController release]; }}六、實現ImagePicker delegate 事件#pragma mark - image picker delegte- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{ [picker dismissViewControllerAnimated:YES completion:^{}]; UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage]; /* 此處info 有六個值 * UIImagePickerControllerMediaType; // an NSString UTTypeImage) * UIImagePickerControllerOriginalImage; // a UIImage 原始圖片 * UIImagePickerControllerEditedImage; // a UIImage 裁剪后圖片 * UIImagePickerControllerCropRect; // an NSValue (CGRect) * UIImagePickerControllerMediaURL; // an NSURL * UIImagePickerControllerReferenceURL // an NSURL that references an asset in the AssetsLibrary framework * UIImagePickerControllerMediaMetadata // an NSDictionary containing metadata from a captured photo */ // 保存圖片至本地，方法見下文 [self saveImage:image withName:@"currentImage.png"]; NSString *fullPath = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:@"currentImage.png"]; UIImage *savedImage = [[UIImage alloc] initWithContentsOfFile:fullPath]; isFullScreen = NO; [self.imageView setImage:savedImage]; self.imageView.tag = 100; }- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker{ [self dismissViewControllerAnimated:YES completion:^{}];}

七、保存圖片高保真壓縮圖片方法

NSData * UIImageJPEGRepresentation ( UIImage *image, CGFloat compressionQuality)此方法可將圖片壓縮，但是圖片質量基本不變，第二個參數即圖片質量參數。 #pragma mark - 保存圖片至沙盒- (void) saveImage:(UIImage *)currentImage withName:(NSString *)imageName{ NSData *imageData = UIImageJPEGRepresentation(currentImage, 0.5); // 獲取沙盒目錄 NSString *fullPath = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:imageName]; // 將圖片寫入文件 [imageData writeToFile:fullPath atomically:NO];}

八、實現點擊圖片預覽功能，滑動放大縮小，帶動畫

-(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 就是觸點的坐標 // 觸點在imageView內，點擊imageView時放大,再次點擊時縮小 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) { // 設置圖片放大動畫 [UIView beginAnimations:nil context:nil]; // 動畫時間 [UIView setAnimationDuration:1]; if (isFullScreen) { // 放大尺寸 self.imageView.frame = CGRectMake(0, 0, 320, 480); } else { // 縮小尺寸 self.imageView.frame = CGRectMake(50, 65, 90, 115); } // commit動畫 [UIView commitAnimations]; } }九、上傳圖片，使用ASIhttpRequest類庫實現，由于本文重點不是網絡請求，故不對ASIHttpRequest詳細講述，只貼出部分代碼ASIFormDataRequest *requestReport = [[ASIFormDataRequest alloc] initWithURL:服務器地址]; NSString *Path = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:@"currentImage.png"]; [requestReport setFile:Path forKey:@"picturepath"];[requestReport buildPostBody];requestReport.delegate = self;[requestReport startAsynchronous];

效果圖如下：