调用系统相册或系统相机,用到的是**UIImagePickerController**
。要遵循两个协议UIImagePickerControllerDelegate,UINavigationControllerDelegate。
具体代码如下:
调用相册:
self.imagePicker = [[UIImagePickerController alloc]init];
self.imagePicker.allowsEditing = YES;
self.imagePicker.delegate = self;
self.imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
self.imagePicker.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypePhotoLibrary];
[self presentViewController:self.imagePicker animated:YES completion:nil];
在上面的sourceType分为三种:
typedef NS_ENUM(NSInteger, UIImagePickerControllerSourceType) {
UIImagePickerControllerSourceTypePhotoLibrary,//相册
UIImagePickerControllerSourceTypeCamera,//相机
UIImagePickerControllerSourceTypeSavedPhotosAlbum//图片库
} __TVOS_PROHIBITED;
当调用系统相机时,使用UIImagePickerControllerSourceTypeCamera这个类型
//处理点击拍照
UIImagePickerControllerSourceType sourceType = UIImagePickerControllerSourceTypeCamera;
if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
[self showHUDMessage:@"相机不可用"];//这里判断相机可不可以用
}else{
self.imagePicker = [[UIImagePickerController alloc]init];
self.imagePicker.allowsEditing = YES;
self.imagePicker.delegate = self;
self.imagePicker.sourceType = sourceType;
self.imagePicker.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypeCamera];
[self presentViewController:self.imagePicker animated:YES completion:nil];
}
实现代理方法:
pragma mark - **************** 选择图片回调方法
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info{
UIImage *image = info[UIImagePickerControllerEditedImage];//获取选择的图片
_lostImageView.image = image;
[self dismissViewControllerAnimated:YES completion:nil];
}
-(void)imagePickerControllerDidCancel:(UIImagePickerController *)picker{
[self dismissViewControllerAnimated:YES completion:nil];
}
写入沙盒:
pragma mark 获取沙盒中完整的文件路径
-(NSString *)getFilePath:(NSString *)fileName{
NSString *filePath;
//获取沙盒Documents目录路径
NSArray *docPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docPath = docPaths[0];
//跟文件名组合起来(使用NSString的实例方法stringByAppendingPathComponent: 组成文件的完整路径)
filePath = [docPath stringByAppendingPathComponent:fileName];
NSLog(@"filePath:%@",filePath);
return filePath;
}
/**
* 将图片写进沙盒
*/
-(void)writeImageToDocPathsWith:(NSString *)imageName{
//1、获取文件管理器(NSFileManager的类方法defaultManager:)
NSFileManager *fileManager = [NSFileManager defaultManager];
//2、检查文件是否存在(NSFileManager的实例方法fileExistsAtPath: ,参数是文件路径,需要调用方法获取)
_filePath = [self getFilePath:[NSString stringWithFormat:@"%@.png",imageName]];
if (![fileManager fileExistsAtPath:_filePath]) {
//2.1、不存在此文件的话,创建该文件(NSFileManager的createFileAtPath: contents: attributes:实例方法)
[fileManager createFileAtPath:_filePath contents:nil attributes:nil];
}
//3、写入文件内容,创建一个NSFileHandle,相当于打开(NSFileHandle的fileHandleForWritingAtPath:类方法)
NSFileHandle *fileHandle = [NSFileHandle fileHandleForWritingAtPath:_filePath];
//4、写入内容(获取内容字符串,调用内容字符串的dataUsingEncoding:实例方法转换成NSData类型,调用NSFileHandle的实例方法writeData:写入文件)
NSData *fileData = UIImagePNGRepresentation(_lostImageView.image); //[fileHandle truncateFileAtOffset:0];//相当于覆盖文件
//文件句柄指向文件末尾,相当于给文件追加内容
[fileHandle seekToEndOfFile];
//写文件
[fileHandle writeData:fileData];
//5、写入完成之后关闭文件(调用NSFileHandle的实例方法closeFile:)
[fileHandle closeFile];
}