iOS學習：調用相機，選擇圖片上傳，帶預覽功能

時間 2019-11-07

標籤 ios 學習調用相機選擇圖片上傳預覽功能欄目 iOS 简体版

原文原文鏈接

1、新建工程ios

2、拖控件，建立映射服務器

3、在.h中加入delegate網絡

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

4、實現按鈕事件app

-(IBAction)chooseImage:(id)sender {
    
    UIActionSheet *sheet;
<p>
// 判斷是否支持相機
</p>
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];
    
}

5、實現actionSheet delegate事件動畫

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;
            }
        }
<p>
// 跳轉到相機或相冊頁面
</p>
UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
        
        imagePickerController.delegate = self;
        
        imagePickerController.allowsEditing = YES;
        
        imagePickerController.sourceType = sourceType;
        
        [self presentViewController:imagePickerController animated:YES completion:^{}];
        
        [imagePickerController release];
    }
}

6、實現ImagePicker delegate 事件ui

#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 裁剪後圖片
     * 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:^{}];
}

7、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，可是圖片質量基本不變，第二個參數即圖片質量參數。 atom

#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];
}

8、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 就是觸點的座標
    
    // 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];
        
    }
    
}

9、上傳圖片，使用ASIhttpRequest類庫實現，因爲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spa

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];

效果圖以下：.net

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