我们在开发的过程中，很多项目中都有很多各式各样的图片，这样一来，难免就会有保存图片到相册的功能，其实很简单，今天空下来了，我详细的写一下：
首先先创建一个UIImageView对象：
@property(nonatomic,strong)UIImageView *img;
然后懒加载一下：
-(UIImageView *)img{
if(!_img) {
_img = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"1.jpg"]];
}
return _img;
}
在viewDidLoad中创建一个长按的手势添加到图片对象上（一般都是长按图片弹出二次确认框保存图片到相册）：
//图片添加到主视图上
[self.view addSubview:self.img];
//1.创建长按手势
UILongPressGestureRecognizer *longTap = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(imglongTapClick:)];
//2.开启人机交互
self.img.userInteractionEnabled = YES;
//3.添加手势
[self.img addGestureRecognizer:longTap];
然后就是实现长按手势的方法
#pragma mark 长按手势弹出警告视图确认
-(void)imglongTapClick:(UILongPressGestureRecognizer*)gesture{
if(gesture.state==UIGestureRecognizerStateBegan){
UIAlertController *alertControl = [UIAlertController alertControllerWithTitle:@"提示" message:@"确认保存图片到相册吗" preferredStyle:UIAlertControllerStyleActionSheet];
UIAlertAction *cancel = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
NSLog(@"取消保存图片");
}];
UIAlertAction *confirm = [UIAlertAction actionWithTitle:@"确认" style:UIAlertActionStyleDestructive handler:^(UIAlertAction * _Nonnull action) {
NSLog(@"确认保存图片");
// 保存图片到相册
UIImageWriteToSavedPhotosAlbum(self.img.image,self,@selector(imageSavedToPhotosAlbum:didFinishSavingWithError:contextInfo:),nil);
}];
[alertControl addAction:cancel];
[alertControl addAction:confirm];
[self presentViewController:alertControl animated:YES completion:nil];
}
}
然后执行保存图片后的回调方法
#pragma mark 保存图片后的回调
- (void)imageSavedToPhotosAlbum:(UIImage*)image didFinishSavingWithError: (NSError*)error contextInfo:(id)contextInfo{
NSString*message =@"提示";
if(!error) {
message =@"成功保存到相册";
UIAlertController *alertControl = [UIAlertController alertControllerWithTitle:@"提示" message:message preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *action = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDestructive handler:^(UIAlertAction * _Nonnullaction) { }];
[alertControl addAction:action];
[self presentViewController:alertControl animated:YES completion:nil];
}else{
message = [errordescription];
UIAlertController *alertControl = [UIAlertController alertControllerWithTitle:@"提示" message:message preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *action = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnullaction) { }];
[alertControl addAction:action];
[self presentViewController:alertControl animated:YES completion:nil];
}
}
这样还没有完成，运行保存图片的时候会出错，因为还没有开启访问相册的权限，这个权限和在相册选取图片的权限可是不一样的，在info.plist中加入key为Privacy - Photo Library Additions Usage Description，Value随便写（例：需要访问您的本地相册）。好了，大功告成！！
