在自定义图像选择器叠加层上执行“使用照片”按钮

Question

我正在为图像选择器控制器创建完全自定义的叠加层。第一阶段很简单：我通过记录/拍摄按钮获得第一个视图，该按钮调用takePicture() 方法。

下一阶段是将 UI 更改为“重拍”或“使用照片”，这也是我自己的设计。 “重拍”大概可以通过再次调用presentViewController 来模仿。我应该如何模仿“使用照片”按钮？

Answer 1

您可以轻松继承UIImagePickerController

Objective-C

@interface CameraViewController : UIImagePickerController

@property (readwrite, nonatomic) NSInteger state; // 0 - auto 1 - on 2 - off

@end

@implementation CameraViewController

- (instancetype)init {
    self = [super init];
    if (self) {
        if (!TARGET_IPHONE_SIMULATOR) {
            self.sourceType = UIImagePickerControllerSourceTypeCamera;
            self.showsCameraControls = NO;
            self.cameraCaptureMode = UIImagePickerControllerCameraCaptureModePhoto;
        } else {
            self.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
        }
        self.modalPresentationStyle = UIModalPresentationFullScreen;
        self.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
        self.allowsEditing = NO;
        self.mediaTypes = @[(NSString *)kUTTypeImage];
        [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(orientationChanged)
                                                     name:UIDeviceOrientationDidChangeNotification
                                                   object:nil];

    }
    return self;
}

- (void)dealloc {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

@end

然后覆盖 viewDidLoad 并通过创建 UIView 对象并将其设置为 self.cameraOverlayView 来根据您的需要自定义 UI。在我的示例中，它是自定义 Flash 按钮。

- (void)viewDidLoad {
    [super viewDidLoad];

    UIView *view = [[UIView alloc] initWithFrame:self.view.bounds];
    view.backgroundColor = [UIColor clearColor];
    UIButton *changeFlashButton = [UIButton buttonWithType:UIButtonTypeCustom];
    changeFlashButton.frame = CGRectMake(70, 27, 40, 40);
    [changeFlashButton setImage:[UIImage imageNamed:@"flash_auto"] forState:UIControlStateNormal];
    self.cameraFlashMode = UIImagePickerControllerCameraFlashModeAuto;
    changeFlashButton.showsTouchWhenHighlighted = YES;
    [changeFlashButton addTarget:self action:@selector(changeFlashValue:) forControlEvents:UIControlEventTouchUpInside];
    [view addSubview:changeFlashButton];
    if (!TARGET_IPHONE_SIMULATOR) {
        self.cameraFlashMode = UIImagePickerControllerCameraFlashModeAuto;
        changeFlashButton.alpha = [[self class] isFlashAvailableForCameraDevice:self.cameraDevice];
        self.cameraOverlayView = view;
    }
}

- (void)changeFlashValue:(UIButton*)aSwitch {
    if (self.state == 0) { //auto - on
        self.state = 1;
        [self.flashSwitch setImage:[UIImage imageNamed:@"flash_on"] forState:UIControlStateNormal];
        self.cameraFlashMode = UIImagePickerControllerCameraFlashModeOn;
        return;
    }
    if (self.state == 1) { //on - off
        self.state = 2;
        [self.flashSwitch setImage:[UIImage imageNamed:@"flash_off"] forState:UIControlStateNormal];
        self.cameraFlashMode = UIImagePickerControllerCameraFlashModeOff;
        return;
    }
    if (self.state == 2) { //off - auto
        self.state = 0;
        [self.flashSwitch setImage:[UIImage imageNamed:@"flash_auto"] forState:UIControlStateNormal];
        self.cameraFlashMode = UIImagePickerControllerCameraFlashModeAuto;
        return;
    }
}

您对相机的控制可能是这样的

请注意，为了不向用户显示“重拍”和“使用照片”按钮，您需要将 allowsEditing 设置为 false

实际上 Swift 2.2+

也是如此

class CameraViewController: UIImagePickerController {

    var state: Int?

    init() {
        super.init(navigationBarClass: nil, toolbarClass: nil)
        #if (arch(i386) || arch(x86_64)) && (os(iOS) || os(watchOS) || os(tvOS)) // any simulator
            self.sourceType = .PhotoLibrary
        #else
            self.sourceType = .Camera
            self.showsCameraControls = false
            self.cameraCaptureMode = .Photo
        #endif

        self.modalPresentationStyle = .FullScreen
        self.modalTransitionStyle = .CrossDissolve
        self.allowsEditing = false
        self.mediaTypes = [UIImagePickerControllerMediaType]
        UIDevice.currentDevice().beginGeneratingDeviceOrientationNotifications()
        NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(orientationChanged), name: UIDeviceOrientationDidChangeNotification, object: nil)
    }

    // strange compiler requirements
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    deinit {
        NSNotificationCenter.defaultCenter().removeObserver(self)
    }

    func orientationChanged() {
        // update to the new orientation
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        let view: UIView = UIView(frame: self.view.bounds)
        view.backgroundColor = UIColor.clearColor()
        var changeFlashButton: UIButton = UIButton(type: .Custom)
        changeFlashButton.frame = CGRectMake(70, 27, 40, 40)
        changeFlashButton.setImage(UIImage(named: "flash_auto"), forState: .Normal)
        self.cameraFlashMode = .Auto
        changeFlashButton.showsTouchWhenHighlighted = true
        changeFlashButton.addTarget(self, action: #selector(changeFlashValue(_:)), forControlEvents: .TouchUpInside)
        view.addSubview(changeFlashButton)
        #if (arch(i386) || arch(x86_64)) && (os(iOS) || os(watchOS) || os(tvOS)) // any simulator
        #else
            self.cameraFlashMode = .Auto
            changeFlashButton.alpha = UIImagePickerController.isFlashAvailableForCameraDevice(self.cameraDevice) ? 1 : 0
        #endif
    }

    func changeFlashValue(aSwitch: UIButton) {
        if self.state == 0 {
            // auto - on
            self.state = 1
            self.flashSwitch.setImage(UIImage.imageNamed("flash_on"), forState: .Normal)
            self.cameraFlashMode = .On
            return
        }
        if self.state == 1 {
            // on - off
            self.state = 2
            self.flashSwitch.setImage(UIImage.imageNamed("flash_off"), forState: .Normal)
            self.cameraFlashMode = .Off
            return
        }
        if self.state == 2 {
            // off - auto
            self.state = 0
            self.flashSwitch.setImage(UIImage.imageNamed("flash_auto"), forState: .Normal)
            self.cameraFlashMode = .Auto
            return
        }
    }
}

Answer 2

您可以通过显示一个视图控制器来模仿使用照片，该控制器允许用户选择编辑拍摄的图像并添加保存和取消按钮。听起来怎么样？