关于图片的等比缩放，从相机和照片选取头像，显示圆形头像

话不多说，应该都是大家经常使用的功能，就总结了下，分享给朋友们，希望多提宝贵意见
1.通过相机和从相片中选择设置头像

//MARK:通过相机和从相片中选择设置头像
//弹出提示框，选择获取头像的方式
//从相册获取图片
- (void)takePictureClick:(UIButton *)sender
{
// /*注：使用，需要实现以下协议：UIImagePickerControllerDelegate,
// UINavigationControllerDelegate
// */
// UIImagePickerController *picker = [[UIImagePickerController alloc]init];
// //设置图片源(相簿)
// picker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
// //设置代理
// picker.delegate = self;
// //设置可以编辑
// picker.allowsEditing = YES;
// //打开拾取器界面
// [self presentViewController:picker animated:YES completion:nil];
UIActionSheet* actionSheet = [[UIActionSheetalloc]
initWithTitle:@"请选择文件来源"
delegate:self
cancelButtonTitle:@"取消"
destructiveButtonTitle:nil
otherButtonTitles:@"照相机",@"摄像机",@"本地相簿",@"本地视频",nil];
[actionSheet showInView:self.view];

}

#pragma 点击按钮选择选取图片的方法
- (void)actionclickedButtonAtIndex:(NSInteger)buttonIndex
{
NSLog(@"buttonIndex = [%ld]",(long)buttonIndex);
switch (buttonIndex) {
case0://照相机
{
UIImagePickerController *imagePicker = [[UIImagePickerControlleralloc]
init];
imagePicker.delegate =self;
imagePicker.allowsEditing =YES;
imagePicker.sourceType =UIImagePickerControllerSourceTypeCamera;
// [self presentModalViewController:imagePicker animated:YES];
[selfpresentViewController:imagePickeranimated:YEScompletion:nil];
}
break;
case1://摄像机
{
UIImagePickerController *imagePicker = [[UIImagePickerControlleralloc]
init];
imagePicker.delegate =self;
imagePicker.allowsEditing =YES;
imagePicker.sourceType =UIImagePickerControllerSourceTypeCamera;
imagePicker.videoQuality =UIImagePickerControllerQualityTypeLow;
// [self presentModalViewController:imagePicker animated:YES];
[selfpresentViewController:imagePickeranimated:YEScompletion:nil];
}
break;
case2://本地相簿
{
UIImagePickerController *imagePicker = [[UIImagePickerControlleralloc]
init];
imagePicker.delegate =self;
imagePicker.allowsEditing =YES;
imagePicker.sourceType =UIImagePickerControllerSourceTypePhotoLibrary;
// [self presentModalViewController:imagePicker animated:YES];
[selfpresentViewController:imagePickeranimated:YEScompletion:nil];
}
break;
case3://本地视频
{
UIImagePickerController *imagePicker = [[UIImagePickerControlleralloc]
init];
imagePicker.delegate =self;
imagePicker.allowsEditing =YES;
imagePicker.sourceType =UIImagePickerControllerSourceTypePhotoLibrary;
// [self presentModalViewController:imagePicker animated:YES];
[selfpresentViewController:imagePickeranimated:YEScompletion:nil];
}
break;
default:
break;
}
}
#pragma mark -
#pragma UIImagePickerController Delegate方法
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary
*)info
{
if ([[info objectForKey:UIImagePickerControllerMediaType] isEqualToString:(__bridge NSString *)kTTypeImage]) {
UIImage *img = [infoobjectForKey:UIImagePickerControllerEditedImage];
[selfperformSelector:@selector(saveImage:) withObject:img
afterDelay:0.5];
}
elseif ([[info objectForKey:UIImagePickerControllerMediaType] isEqualToString:(__bridge
NSString *)kUTTypeMovie]) {
NSString *videoPath = [[infoobjectForKey:UIImagePickerControllerMediaURL]path];
self.fileData = [NSData dataWithContentsOfFile:videoPath];
}
// [picker dismissModalViewControllerAnimated:YES];
[picker dismissViewControllerAnimated:YEScompletion:nil];
}
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
// [picker dismissModalViewControllerAnimated:YES];
[picker dismissViewControllerAnimated:YEScompletion:nil];
}
- (void)saveImage:(UIImage *)image {
// NSLog(@"保存头像！");
// [userPhotoButton setImage:image forState:UIControlStateNormal];
BOOL success;
NSFileManager *fileManager = [NSFileManagerdefaultManager];
NSError *error;

NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,
YES);
NSString *documentsDirectory = [pathsobjectAtIndex:0];
NSString *imageFilePath = [documentsDirectorystringByAppendingPathComponent:@"selfPhoto.jpg"];
NSLog(@"imageFile->>%@",imageFilePath);
success = [fileManager fileExistsAtPath:imageFilePath];
if(success) {
success = [fileManager removeItemAtPath:imageFilePatherror:&error];
}
// UIImage *smallImage=[self scaleFromImage:image toSize:CGSizeMake(80.0f, 80.0f)];//将图片尺寸改为80*80
UIImage *smallImage = [selfthumbnailWithImageWithoutScale:imagesize:CGSizeMake(93,93)];
[UIImageJPEGRepresentation(smallImage,1.0f)
writeToFile:imageFilePathatomically:YES];//写入文件
UIImage *selfPhoto = [UIImageimageWithContentsOfFile:imageFilePath];//读取图片文件
// [userPhotoButton setImage:selfPhoto forState:UIControlStateNormal];
self.imv.image = selfPhoto;
}
// 改变图像的尺寸，方便上传服务器
- (UIImage *) scaleFromImage: (UIImage *) image toSize: (CGSize) size
{
UIGraphicsBeginImageContext(size);
[image drawInRect:CGRectMake(0,0,
size.width, size.height)];
UIImage *newImage =UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
//MARK: 2.保持原始图片的长宽比，生成需要尺寸的图片
//2.保持原来的长宽比，生成一个缩略图
- (UIImage *)thumbnailWithImageWithoutScale:(UIImage *)image size:(CGSize)asize
{
UIImage *newimage;
if (nil == image) {
newimage = nil;
}
else{
CGSize oldsize = image.size;
CGRect rect;
if (asize.width/asize.height > oldsize.width/oldsize.height)
{
rect.size.width = asize.height*oldsize.width/oldsize.height;
rect.size.height = asize.height;
rect.origin.x = (asize.width - rect.size.width)/2;
rect.origin.y =0;
}
else{
rect.size.width = asize.width;
rect.size.height = asize.width*oldsize.height/oldsize.width;
rect.origin.x =0;
rect.origin.y = (asize.height - rect.size.height)/2;
}
UIGraphicsBeginImageContext(asize);
CGContextRef context =UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [[UIColorclearColor]
CGColor]);
UIRectFill(CGRectMake(0,0,
asize.width, asize.height));//clear background
[image drawInRect:rect];
newimage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
}
return newimage;
}

//MARK:3.显示圆形头像
- (void)showRound{
NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,
YES);
NSString *documentsDirectory = [pathsobjectAtIndex:0];
NSString *imageFilePath = [documentsDirectorystringByAppendingPathComponent:@"selfPhoto.jpg"];
NSLog(@"imageFile->>%@",imageFilePath);
UIImage *selfPhoto = [UIImageimageWithContentsOfFile:imageFilePath];
self.imv.image = selfPhoto;
[self.imv.layersetCornerRadius:CGRectGetHeight([self.imvbounds])
/ 2]; //修改半径，实现头像的圆形化
self.imv.layer.masksToBounds
= YES;

}