一.從相冊(cè)里面選擇圖片到App中

1.選擇單張

    1>.UIImagePickerController(自帶選擇界面的)
    2>.AssetsLibrary(選擇界面需要開發(fā)者自己搭建)
    3>.Photos(選擇界面需要開發(fā)者自己搭建)

2.多張圖片選擇(圖片數(shù)量>2)

    1>.AssetsLibrary
    2>.Photos

二.利用相機(jī)拍一張照片到APP

   1>.UIImagePickerController
   2>.AVcaptureSeccion.可以定義拍照界面樣式

選擇單張照片

/// 選擇照片
- (IBAction)selectPhoto:(UIButton *)sender {
    UIAlertController *alterConroller = [UIAlertController alertControllerWithTitle:@"請(qǐng)選擇方式" message:nil preferredStyle:UIAlertControllerStyleActionSheet];
    UIAlertAction *cameraAction = [UIAlertAction actionWithTitle:@"照相機(jī)" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        [self openCamera];
    }];
    UIAlertAction *albumAction = [UIAlertAction actionWithTitle:@"相冊(cè)" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
        [self openAlbum];
    }];
    [alterConroller addAction:albumAction];
    [alterConroller addAction:cameraAction];
    [self presentViewController:alterConroller animated:YES completion:nil];
}
/// 打開照相機(jī)
- (void)openCamera{
    //UIImagePickerControllerSourceTypePhotoLibrary, 從所有相冊(cè)選擇
    //UIImagePickerControllerSourceTypeCamera, //拍一張照片
    //UIImagePickerControllerSourceTypeSavedPhotosAlbum//從moments選擇一張照片
    //判斷照相機(jī)能否使用
    if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) return;
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.sourceType = UIImagePickerControllerSourceTypeCamera;
    picker.delegate = self;
    [self presentViewController:picker animated:YES completion:nil];
}
/// 打開相冊(cè)
- (void)openAlbum{
    //UIImagePickerControllerSourceTypePhotoLibrary, 從所有相冊(cè)選擇
    //UIImagePickerControllerSourceTypeCamera, //拍一張照片
    //UIImagePickerControllerSourceTypeSavedPhotosAlbum//從moments選擇一張照片
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
    picker.delegate = self;
    [self presentViewController:picker animated:YES completion:nil];
}
#pragma mark - ******UIImagePickerControllerDelegate******
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info{
    [picker dismissViewControllerAnimated:YES completion:nil];
    self.imageView.image = info[UIImagePickerControllerOriginalImage];
    NSLog(@"%@",info);
}

• 注意事項(xiàng)

UIImagePickerController的代理有2個(gè)遵循2個(gè)代理<UINavigationControllerDelegate, UIImagePickerControllerDelegate>