IOS开发---菜鸟学习之路--（十五）-如何实现拍照功能

本章将来讲解下如何实现拍照的功能

我们需要的实现的效果是 

    

好了 直接开始内容吧

首先我们需要新建一个ViewController

就叫AddPictureViewController

然后选择.h文件进行如下修改

#import <UIKit/UIKit.h>

@interface AddPictureViewController : UIViewController<UIImagePickerControllerDelegate,UINavigationControllerDelegate,UIAlertViewDelegate>
{
    UITextView *contenttextview;
    UIImageView *contentimageview;
    NSString *lastChosenMediaType;

}
@property(nonatomic,retain) IBOutlet UITextView *contenttextview;
@property(nonatomic,retain)  IBOutlet   UIImageView *contentimageview;
@property(nonatomic,copy)        NSString *lastChosenMediaType;
-(IBAction)buttonclick:(id)sender;

@end

我们需要添加以下两个库

QuartzCore

MobileCoreServices

在项目的General里找到  linked Frameworks and libraries 添加两个类库

然后修改XIB文件

并建立相关链接

最后就是.m文件部分的代码了。

我就直接上代码了 大家可以直接复制过去 然后再理解

#import "AddPictureViewController.h"
#import <QuartzCore/QuartzCore.h>
#import <QuartzCore/CoreAnimation.h>
#import <MobileCoreServices/UTCoreTypes.h>
@interface AddPictureViewController ()

@end

@implementation AddPictureViewController
@synthesize contentimageview;
@synthesize contenttextview;
@synthesize lastChosenMediaType;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
}
-(IBAction)buttonclick:(id)sender
{
    UIAlertView *alert=[[UIAlertView alloc] initWithTitle:@"请选择图片来源" message:@"" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"拍照",@"从手机相册选择", nil];
    [alert show];
}
- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
#pragma 拍照选择模块
-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
    if(buttonIndex==1)
        [self shootPiicturePrVideo];
    else if(buttonIndex==2)
        [self selectExistingPictureOrVideo];
}
#pragma  mark- 拍照模块
//从相机上选择
-(void)shootPiicturePrVideo{
    [self getMediaFromSource:UIImagePickerControllerSourceTypeCamera];
}
//从相册中选择
-(void)selectExistingPictureOrVideo{
    [self getMediaFromSource:UIImagePickerControllerSourceTypePhotoLibrary];
}
#pragma 拍照模块
-(void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
    self.lastChosenMediaType=[info objectForKey:UIImagePickerControllerMediaType];
    if([lastChosenMediaType isEqual:(NSString *) kUTTypeImage])
    {
        UIImage *chosenImage=[info objectForKey:UIImagePickerControllerEditedImage];
        contentimageview.image=chosenImage;
    }
    if([lastChosenMediaType isEqual:(NSString *) kUTTypeMovie])
    {
        UIAlertView *alert=[[UIAlertView alloc] initWithTitle:@"提示信息!" message:@"系统只支持图片格式" delegate:nil cancelButtonTitle:@"确认" otherButtonTitles: nil];
        [alert show];
        
    }
    [picker dismissModalViewControllerAnimated:YES];
}
-(void) imagePickerControllerDidCancel:(UIImagePickerController *)picker{
    [picker dismissModalViewControllerAnimated:YES];
}
-(void)getMediaFromSource:(UIImagePickerControllerSourceType)sourceType
{
    NSArray *mediatypes=[UIImagePickerController availableMediaTypesForSourceType:sourceType];
    if([UIImagePickerController isSourceTypeAvailable:sourceType] &&[mediatypes count]>0){
        NSArray *mediatypes=[UIImagePickerController availableMediaTypesForSourceType:sourceType];
        UIImagePickerController *picker=[[UIImagePickerController alloc] init];
        picker.mediaTypes=mediatypes;
        picker.delegate=self;
        picker.allowsEditing=YES;
        picker.sourceType=sourceType;
        NSString *requiredmediatype=(NSString *)kUTTypeImage;
        NSArray *arrmediatypes=[NSArray arrayWithObject:requiredmediatype];
        [picker setMediaTypes:arrmediatypes];
        [self presentModalViewController:picker animated:YES];
    }
    else{
        UIAlertView *alert=[[UIAlertView alloc] initWithTitle:@"错误信息!" message:@"当前设备不支持拍摄功能" delegate:nil cancelButtonTitle:@"确认" otherButtonTitles: nil];
        [alert show];
    }
}
static UIImage *shrinkImage(UIImage *orignal,CGSize size)
{
    CGFloat scale=[UIScreen mainScreen].scale;
    CGColorSpaceRef colorSpace=CGColorSpaceCreateDeviceRGB();
    CGContextRef context=CGBitmapContextCreate(NULL, size.width *scale,size.height*scale, 8, 0, colorSpace, kCGImageAlphaPremultipliedFirst);
    CGContextDrawImage(context, CGRectMake(0, 0, size.width*scale, size.height*scale), orignal.CGImage);
    CGImageRef shrunken=CGBitmapContextCreateImage(context);
    UIImage *final=[UIImage imageWithCGImage:shrunken];
    CGContextRelease(context);
    CGImageRelease(shrunken);
    return  final;
}

@end

最后就实现效果了