Enabling the photo library button on the UIImagePickerController

问题

Does anyone know how to enable the photo album button on the UIImagePickerController when its in the camera mode? Like how the camera app on on the iphone can toggle between image and video taking and also has the button to view the photo library?

回答1:

I'm afraid that this can't be done in that easy way (just enable or disable some magic feature). For some simple requirement, you can use cameraOverlayView and showsCameraControls to make the implementation.

If you want to switch between photo/video mode, i think you can check this demo: http://developer.apple.com/library/ios/#samplecode/AVCam/Introduction/Intro.html

回答2:

This can be done via the following lines:

- (void) navigationController: (UINavigationController *) navigationController  willShowViewController: (UIViewController *) viewController animated: (BOOL) animated {
    if (imagePickerController.sourceType == UIImagePickerControllerSourceTypePhotoLibrary) {
        UIBarButtonItem* button = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCamera target:self action:@selector(showCamera:)];
        viewController.navigationItem.rightBarButtonItems = [NSArray arrayWithObject:button];
    } else {
        UIBarButtonItem* button = [[UIBarButtonItem alloc] initWithTitle:@"Library" style:UIBarButtonItemStylePlain target:self action:@selector(showLibrary:)];
        viewController.navigationItem.leftBarButtonItems = [NSArray arrayWithObject:button];
        viewController.navigationItem.title = @"Take Photo";
        viewController.navigationController.navigationBarHidden = NO; // important
    }
}

- (void) showCamera: (id) sender {
    imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;
}

- (void) showLibrary: (id) sender {
    imagePickerController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
}

回答3:

Here is an example app and very simple library that lets you get the Take Photo or Choose from Library just like Facebook does. https://github.com/fulldecent/FDTake

回答4:

I have done this tweaking Apple's PhotoPicker example app. I have removed all the camera controls and added my own button. When clicked, UIImagePickerControllerSourceType is set to the UIImagePickerControllerSourceTypePhotoLibrary.

The tricky part for me was "dismissing" (might be technically the wrong word) the Photo Library after the image was picked. I did this by setting the source type back to UIImagePickerControllerSourceTypeCamera. This brings back the camera overlay view.

ViewController.h

#import <UIKit/UIKit.h>
#import <CoreGraphics/CoreGraphics.h>
#import <ImageIO/ImageIO.h>


@interface ViewController : UIViewController <UIImagePickerControllerDelegate> {

//

}

@property (nonatomic, strong) UIImagePickerController *imagePicker;
- (IBAction)uploadNewPhotoTapped:(id)sender;
@end


ViewController.m

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

 //Other code

- (IBAction)uploadNewPhotoTapped:(id)sender {

    UIImagePickerController *imagePickController=[[UIImagePickerController alloc]init];
    //You can use isSourceTypeAvailable to check

    if ([UIImagePickerController    isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
    {
        imagePickController.sourceType=UIImagePickerControllerSourceTypeCamera;
        imagePickController.showsCameraControls=YES;
        //  self.usingPopover = NO;
    }
    else if ([UIImagePickerController  isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) {//Check PhotoLibrary  available or not
        imagePickController.sourceType=UIImagePickerControllerSourceTypePhotoLibrary;
        imagePickController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
    }
    else if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeSavedPhotosAlbum]) //Check front Camera available or not
        imagePickController.sourceType=UIImagePickerControllerSourceTypeSavedPhotosAlbum;
    //else //!!!!!!!!!!!exception

    imagePickController.delegate=self;
    imagePickController.allowsEditing=NO;

    [self presentModalViewController:imagePickController animated:YES];
}


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

    UIImage *originalImage=[info objectForKey:UIImagePickerControllerOriginalImage];

    //Do whatever with your image   
    NSData *data = UIImageJPEGRepresentation (
                                          originalImage,
                                          1.0
                                          );

    [self dismissModalViewControllerAnimated:YES];
}

   // Other code
   @end

回答5:

Swift2 version of @epsilontik code:

    //mediaPicker is your UIImagePickerController
func navigationController(navigationController: UINavigationController, willShowViewController viewController: UIViewController, animated: Bool) {
    if(mediaPicker.sourceType == UIImagePickerControllerSourceType.PhotoLibrary){
        let button = UIBarButtonItem(title: "Take picture", style: UIBarButtonItemStyle.Plain, target: self, action: "showCamera")
        viewController.navigationItem.rightBarButtonItem = button
    }else{
        let button = UIBarButtonItem(title: "Choose picture", style: UIBarButtonItemStyle.Plain, target: self, action: "choosePicture")
        viewController.navigationItem.rightBarButtonItem = button
        viewController.navigationController?.navigationBarHidden = false
        viewController.navigationController?.navigationBar.translucent = true
    }
}

func showCamera(){
    mediaPicker.sourceType = UIImagePickerControllerSourceType.Camera
}

func choosePicture(){
    mediaPicker.sourceType = UIImagePickerControllerSourceType.PhotoLibrary
}

来源：https://stackoverflow.com/questions/8528880/enabling-the-photo-library-button-on-the-uiimagepickercontroller