UIImagePickerController and a Simple Example

iPhone's camera is really fun for me.
Here is my note about UIImagePickerController and a simple example.


Three ways to pick image

//Pick from Camera
imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;

//Pick from all folders in the gallery
imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

//Pick from PhotosAlbum(camera roll)
imagePicker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;

Check camera's existence

//Check Camera available or not
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])

//Check PhotoLibrary available or not
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) 

//Check front Camera available or not
if ([UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront])

UIImagePickerControllerDelegate protocol

//Tells the delegate that the user picked a still image or movie.
 (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
}

//Tells the delegate that the user cancelled the pick operation.
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
}

//Tells the delegate that the user picked an image. (Deprecated in iOS 3.0. Use imagePickerController:didFinishPickingMediaWithInfo: instead.)
- (void)imagePickerController:(UIImagePickerController *)picker 
didFinishPickingImage:(UIImage *)image 
  editingInfo:(NSDictionary *)editingInfo
{
}

A simple basic camera code example:
(UIKit,Foundation,CoreGraphics)

ViewController.h

#import <UIKit/UIKit.h>
@interface ViewController : UIViewController<UIImagePickerControllerDelegate,UINavigationControllerDelegate>

@property(nonatomic,retain)IBOutlet UIImageView *imageView;
@property(nonatomic,retain)IBOutlet UIBarButtonItem *saveImageBotton;

-(IBAction)showCameraAction:(id)sender;
-(IBAction)saveImageAction:(id)sender;

@end

Protocol UIImagePickerController and UINavigationController.
UIImagePickerController is a subclass of the UINavigationController.
UIImageView can't show video,need to use MPMoviePlayer instance(Property view).

ViewController.m

#import "ViewController.h"

@implementation ViewController

@synthesize imageView;
@synthesize saveImageBotton;

#pragma mark - Show camera

-(IBAction)showCameraAction:(id)sender
{
    UIImagePickerController *imagePickController=[[UIImagePickerController alloc]init];
    imagePickController.sourceType=UIImagePickerControllerSourceTypeCamera;
    imagePickController.delegate=self;
    imagePickController.allowsEditing=TRUE;
    [self presentModalViewController:imagePickController animated:YES];
    [imagePickController release];
}

#pragma mark - Save photo

-(IBAction)saveImageAction:(id)sender
{
    UIImage *image=imageView.image;
    UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
    saveImageBotton.enabled=FALSE;
}

#pragma mark - When finish shoot

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    UIImage *image=[info objectForKey:UIImagePickerControllerEditedImage];
    imageView.image=image;
    saveImageBotton.enabled=TRUE;
    [self dismissModalViewControllerAnimated:YES];
}

#pragma mark - Release object

- (void)dealloc {
    [imageView release];
    [saveImageBotton release];
    [super dealloc];
}

#pragma mark

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Release any cached data, images, etc that aren't in use.
}

#pragma mark - View lifecycle

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

- (void)viewDidUnload
{
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
}

- (void)viewWillDisappear:(BOOL)animated
{
 [super viewWillDisappear:animated];
}

- (void)viewDidDisappear:(BOOL)animated
{
 [super viewDidDisappear:animated];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return YES;
}

@end

PS1:
According to the following,you can set imageView Mode
imageView.contentMode = UIViewContentModeScaleAspectFit;
you can set it to any of the following

UIViewContentModeScaleToFill,
UIViewContentModeScaleAspectFit,
UIViewContentModeScaleAspectFill,
UIViewContentModeRedraw,
UIViewContentModeCenter,
UIViewContentModeTop,
UIViewContentModeBottom,
UIViewContentModeLeft,
UIViewContentModeRight,
UIViewContentModeTopLeft,
UIViewContentModeTopRight,
UIViewContentModeBottomLeft,
UIViewContentModeBottomRight


PS2:
[Other Properties]
cameraCaptureMode
--->UIImagePickerControllerCameraCaptureModePhoto(Default) or UIImagePickerControllerCameraCaptureModeVideo

cameraDevice
--->UIImagePickerControllerCameraDeviceFront or UIImagePickerControllerCameraDeviceRear(Default)

cameraFlashMode
--->Close：UIImagePickerControllerCameraFlashModeOff = -1
--->Auto：UIImagePickerControllerCameraFlashModeAuto = 0 (Default)
--->Open：UIImagePickerControllerCameraFlashModeOn = 1

cameraOverlayView
--->about Customized