一、UIImagePickerController
这个文章大部分摘别人的，自己总结下来更方便用一点
UIImagePickerController是系统提供的用来获取图片和视频的接口
获取的途径为相机，图库，相册
分为以下几个步骤：
- 初始化UIImagePickerController 类；
- 设置UIImagePickerController 实例的数据来源类型（下面解释）；
- 设置代理；
- 如果需要做图片修改的话设置allowsEditing =yes。
数据来源的类型有三种
enum {
UIImagePickerControllerSourceTypePhotoLibrary ,//来自图库
UIImagePickerControllerSourceTypeCamera ,//来自相机
UIImagePickerControllerSourceTypeSavedPhotosAlbum //来自相册
};
用之前要检测设备是否支持
if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
{
NSLog(@"支持相机");
}
if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary])
{
NSLog(@"支持图库");
}
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeSavedPhotosAlbum])
{
NSLog(@"支持相片库");
}
二、UIImagePickerController属性详解：
//指定使用照相机模式,可以指定使用相册／照片库
imagepicker.sourceType = UIImagePickerControllerSourceTypeCamera;
//设置当拍照完或在相册选完照片后，是否跳到编辑模式进行图片剪裁。只有当showsCameraControls属性为true时才有效果
imagepicker.allowsEditing = YES;
//设置拍照时的下方的工具栏是否显示，如果需要自定义拍摄界面，则可把该工具栏隐藏
imagepicker.showsCameraControls = YES;
//设置使用后置摄像头，可以使用前置摄像头
imagepicker.cameraDevice = UIImagePickerControllerCameraDeviceRear;
//设置闪光灯模式
/* typedef NS_ENUM(NSInteger, UIImagePickerControllerCameraFlashMode) { UIImagePickerControllerCameraFlashModeOff = -1, UIImagePickerControllerCameraFlashModeAuto = 0, UIImagePickerControllerCameraFlashModeOn = 1 }; */
imagepicker.cameraFlashMode = UIImagePickerControllerCameraFlashModeAuto;
//设置相机支持的类型，拍照和录像
imagepicker.mediaTypes = @[(NSString*)kUTTypeImage,(NSString*)kUTTypeMovie];
//设置拍摄时屏幕的view的transform属性，可以实现旋转，缩放功能
// imagepicker.cameraViewTransform = CGAffineTransformMakeRotation(M_PI*45/180);
// imagepicker.cameraViewTransform = CGAffineTransformMakeScale(1.5, 1.5);
//所有含有cameraXXX的属性都必须要sourceType是UIImagePickerControllerSourceTypeCamera时设置才有效果，否则会有异常
//设置UIImagePickerController的代理
imagepicker.delegate = self;
-(void)showCamera{ //用模态方式呈现imagepicker，这个方法之后就会跳到对应的源位置，相机或者相册图库 [self presentModalViewController:imagepicker animated:YES];}
代理方法
当用户选取完成后调用；
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker;
当用户取消选取时调用；
- (void)imagePickerController:(UIImagePickerController *)picker
didFinishPickingMediaWithInfo:(NSDictionary *)info;
最后是我自己的实现，一般也就这么用了，点击相框进入相册，选一张图点choose，出来后相框就是选择的图了
#import "ThirdViewController.h"
//签订协议
@interface ThirdViewController ()<UINavigationControllerDelegate,UIImagePickerControllerDelegate>
@property (nonatomic,retain)UIImageView *myImageView;
@end
@implementation ThirdViewController
- (void)viewDidLoad {
[super viewDidLoad];
//创建一块imageView
_myImageView = [[UIImageView alloc]initWithFrame:CGRectMake((414-300)/2, 200, 300, 300)];
_myImageView.backgroundColor = [UIColor whiteColor];
//打开交互
_myImageView.userInteractionEnabled = YES;
[self.view addSubview:_myImageView];
//添加一个手势
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(selectImage:)];
[_myImageView addGestureRecognizer:tapGesture];
}
//实现手势的方法，进入相册
-(void)selectImage:(UIButton*)sender
{ //创建ImagePickController
UIImagePickerController *myPicker = [[UIImagePickerController alloc]init];
//创建源类型
UIImagePickerControllerSourceType mySourceType = UIImagePickerControllerSourceTypePhotoLibrary;
myPicker.sourceType = mySourceType;
//设置代理
myPicker.delegate = self;
//设置可编辑
myPicker.allowsEditing = YES;
//通过模态的方式推出系统相册
[self presentViewController:myPicker animated:YES completion:^{
NSLog(@"进入相册");
}];
}
#pragma mark -- 实现imagePicker的代理方法
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info
{
//取得所选取的图片,原大小,可编辑等，info是选取的图片的信息字典
UIImage *selectImage = [info objectForKey:UIImagePickerControllerEditedImage];
//设置图片进相框
self.myImageView.image = selectImage;
[picker dismissViewControllerAnimated:YES completion:^{
NSLog(@"模态返回") ;
}];
}
@end
效果如下
中间有个相框，点一下进入相册，在相册中选择一张图片，点choose，出来相框的图片就变了
