如何檢測用戶何時點擊UIImagePickerController中的「Record」按鈕？

Question

我想，當用戶點擊錄製按鈕在UIImagePicker控制器，但沒有委託方法告訴我們，當他們達到創紀錄顯示倒計時。我能設置最大持續時間，但我想給1分鐘警告或東西的影響，但我不知道該怎麼做

videoPickerCtrl = [[UIImagePickerController alloc] init]; 
videoPickerCtrl.delegate = self; 
videoPickerCtrl.sourceType =  UIImagePickerControllerSourceTypeCamera; 
videoPickerCtrl.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:videoPickerCtrl.sourceType]; 
videoPickerCtrl.allowsEditing = NO; 
videoPickerCtrl.videoMaximumDuration = 170; 
videoPickerCtrl.mediaTypes = [NSArray arrayWithObject:(NSString *)kUTTypeMovie]; 

編輯：

我做不到找到一個解決方案，所以我做了我自己的自定義視頻選取控制器。希望別人能找到它有用： https://github.com/saliksyed/CustomVideoCapture

Answer 1

好。所以我很確定我想實現的目標是不可能的。我將重新創建標準的UIImagePickerController界面，用於使用AVFoundation作爲後端的視頻。希望一旦完成，我會在github上發佈它。

Answer 2

當用戶點擊該按鈕後，你可以提供自己的錄音按鈕你沒有得到通知：設置圖像拾取，以隱藏其標準控件（showsCameraControls），並提供一個自定義覆蓋視圖（cameraOverlayView）。在該覆蓋視圖中，放置一個您連接到目標/操作的自定義按鈕，並在您調用-startVideoCapture的操作方法中。

Answer 3

我創建了您要使用自定義重疊視圖尋找同樣的效果。

你需要創建一個模態窗口的UIVideoEditorController實例誰的videoPath酒店距離imagePickerController:didFinishPickingMediaWithInfo:方法，你應該在處理的userInfo關鍵UIImagePickerControllerMediaURL。

HTH

Answer 4

對於其他人，這可以，如果你使用的UIImagePickerController定製覆蓋圖來完成。只需將所需的所有控件添加到視圖中，然後將該父視圖設置爲屬性cameraOverlayView。

Answer 5

在一個完美的世界裏，你會希望蘋果提供只是一對夫婦的代表，將做到這一點的。例如：

• （無效）imagePickerControllerDidStartVideoCapturing：（的UIImagePickerController *）選擇器
• （無效）imagePickerControllerDidStopVideoCapturing：（的UIImagePickerController *）選擇器

現實然而（按照蘋果文檔）是：

• 針對UIImagePickerController的協議太基本了，無法做到這一點
• 此類旨在原樣使用，不支持子類
• 此類的視圖層次是私人的，不能修改

文檔還指出：「你可以自定義視圖分配給cameraOverlayView屬性並使用該視圖呈現附加信息或管理攝像頭界面和您的代碼之間的交互「。

在我的應用程序中，我需要提供「UIProgressView」以指示可以錄製視頻的時間。爲了做到這一點，我需要能夠檢測視頻捕捉開始的時刻。

我不想禁用本機相機控制，因爲它們很酷，而且我很懶，所以我不想花太多時間重新發明輪子。我所需要的只是捕捉一個大紅色按鈕被啓動或停止錄製的事實。

我的解決辦法是「覆蓋」原來的啓動/停止與自定義視圖錄制按鈕，讓用戶交互的這一觀點如下：

overlayView = [[UIView alloc] initWithFrame:self.view.frame]; 

// Start/ Stop fake button 
UIView *ssView = [[UIView alloc] initWithFrame:CGRectMake(self.view.frame.size.width/2 - 35, self.view.frame.size.height - 71, 70, 70)]; 
[ssView setUserInteractionEnabled:YES]; 

// Background color below is only there to make sure my pseudo-button overlaps native Start/Stop button. Comment out the line below to leave it transparent 
[ssView setBackgroundColor:[UIColor colorWithRed:0 green:1 blue:0 alpha:0.5f]]; 

UITapGestureRecognizer *t = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)]; 
[ssView addGestureRecognizer:t]; 

[overlayView addSubview:ssView]; 

// My own progress bar 
UIProgressView *p = [[UIProgressView alloc] initWithProgressViewStyle:UIProgressViewStyleDefault]; 
[p setTintColor:[UIColor redColor]]; 
[p setCenter:CGPointMake(30, 130)]; 
[p setTransform:CGAffineTransformMakeRotation(M_PI/2)]; 
[p setProgress:0]; 

[overlayView addSubview:p]; 

pickerController.cameraOverlayView = overlayView; 

然後我定義的事件處理程序用於抽頭如下：

-(void)tapped:(id)sender { 

    if (isRecording) { 
     [pickerController stopVideoCapture]; 
     NSLog(@"Video capturing stopped..."); 
     // add your business logic here ie stop updating progress bar etc... 
     [pickerController.cameraOverlayView setHidden:YES]; 
     isRecording = NO; 
     return; 
    } 

    if ([pickerController startVideoCapture]) { 
     NSLog(@"Video capturing started..."); 
     // add your business logic here ie start updating progress bar etc... 
     isRecording = YES; 
    } 

} 

接口文件的全碼：

#import <UIKit/UIKit.h> 
#import <MobileCoreServices/MobileCoreServices.h> 

@interface ViewController : UIViewController <UIImagePickerControllerDelegate> 
- (IBAction)openCamera:(id)sender; 

@end 

Implementati on file：

#import "ViewController.h" 

@interface ViewController() { 
    UIImagePickerController *pickerController; 
    UIView* overlayView; 
    BOOL isRecording; 
} 

@end 

@implementation ViewController 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    // Do any additional setup after loading the view, typically from a nib. 

    isRecording = NO; 

    pickerController = [[UIImagePickerController alloc] init]; 
    pickerController.delegate = self; 
    pickerController.allowsEditing = NO; 
    pickerController.videoMaximumDuration = 30.0f; 
    pickerController.sourceType = UIImagePickerControllerSourceTypeCamera; 
    pickerController.mediaTypes = [[NSArray alloc] initWithObjects: (NSString *) kUTTypeMovie, nil]; 

    // I want default controls be available here... 
    pickerController.showsCameraControls = YES; 

    overlayView = [[UIView alloc] initWithFrame:self.view.frame]; 

    // Start/ Stop fake button 
    UIView *ssView = [[UIView alloc] initWithFrame:CGRectMake(self.view.frame.size.width/2 - 35, self.view.frame.size.height - 71, 70, 70)]; 
    [ssView setUserInteractionEnabled:YES]; 
    // Background color below is only there to make sure myt pseudo-button overlaps native Start/Stop button 
    [ssView setBackgroundColor:[UIColor colorWithRed:0 green:1 blue:0 alpha:0.5f]]; 

    UITapGestureRecognizer *t = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)]; 
    [ssView addGestureRecognizer:t]; 

    [overlayView addSubview:ssView]; 

    // My own progress bar 
    UIProgressView *p = [[UIProgressView alloc] initWithProgressViewStyle:UIProgressViewStyleDefault]; 
    [p setTintColor:[UIColor redColor]]; 
    [p setCenter:CGPointMake(30, 130)]; 
    [p setTransform:CGAffineTransformMakeRotation(M_PI/2)]; 
    [p setProgress:0]; 

    [overlayView addSubview:p]; 

    pickerController.cameraOverlayView = overlayView; 

} 

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker { 
    // Cancel button tapped 
    [picker dismissViewControllerAnimated:YES completion:nil]; 
} 

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

    NSLog(@"Got image : %@", info); 
    [picker dismissViewControllerAnimated:YES completion:nil]; 

    // Do something with video captured 
} 

-(void)tapped:(id)sender { 

    if (isRecording) { 
     [pickerController stopVideoCapture]; 
     NSLog(@"Video capturing stopped..."); 
     // add your business logic here ie stop updating progress bar etc... 
     [pickerController.cameraOverlayView setHidden:YES]; 
     isRecording = NO; 
     return; 
    } 

    if ([pickerController startVideoCapture]) { 
     NSLog(@"Video capturing started..."); 
     // add your business logic here ie start updating progress bar etc... 
     isRecording = YES; 
    } 

} 

- (IBAction)openCamera:(id)sender { 
    [pickerController.cameraOverlayView setHidden:NO]; 
    [self presentViewController:pickerController animated:YES completion:nil];  
} 
@end 

您可能已經注意到，一旦視頻捕捉停止後，我隱藏了cameraOverlayView。

[pickerController.cameraOverlayView setHidden:YES]; 

這是爲了讓「重拍/播放和使用」本地控制工作視頻錄製結束後正常。