이것은 화판의 항목 부분 코드이다

잠금 해제 후 UINavgationController 추가

FunctionViewController *vc = [[FunctionViewController alloc] init];
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:vc];
[nav setNavigationBarHidden:YES];
[self presentViewController:nav animated:YES completion:nil];

도판을 그리면 손가락 조작이 화면을 떠난 후에도 계속 그림을 그릴 수 있다

//       ，lineModel     ，       CGMutablePathRef
@property(nonatomic, strong) NSMutableArray *lineModels; 

  - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
      LineModel *lineModel = [[LineModel alloc] init];
      lineModel.path = CGPathCreateMutableCopy(self.path); //   self.path         
      lineModel.lineWidth = 2;
      lineModel.color = [UIColor blackColor];
      [self.lineModels addObject:lineModel];
      
      CGPathRelease(self.path);
      self.path = nil;
      
  }

- (void)drawRect:(CGRect)rect {
    //           
    [self.lineModels enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        LineModel *model = obj;
        CGContextRef context = UIGraphicsGetCurrentContext();
        CGContextAddPath(context, model.path);
        CGContextSetLineWidth(context, model.lineWidth);
        CGContextSetStrokeColorWithColor(context, model.color.CGColor);
        CGContextDrawPath(context, kCGPathStroke);
    }];
    
    if (self.path) {
        CGContextRef context = UIGraphicsGetCurrentContext();
        CGContextAddPath(context, self.path);
        CGContextSetLineWidth(context, 2);
        CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
        CGContextDrawPath(context, kCGPathStroke);
    }
}

다양한 작업을 위한 새 ToolView 클래스

#import 

@interface ToolView : UIView

@property (nonatomic, copy) void(^penBlock)(void);
@property (nonatomic, copy) void(^eraserBlock)(void);
@property (nonatomic, copy) void(^colorBlock)(void);
@property (nonatomic, copy) void(^undoBlock)(void);
@property (nonatomic, copy) void(^clearBlock)(void);
@property (nonatomic, copy) void(^saveBlock)(void);
@property (nonatomic, copy) void(^sliderBlock)(CGFloat width);

@end

-(void) configToolView {
    
    __weak typeof (self) weakself = self;
    self.toolView.penBlock = ^{
        weakself.bEraserMode = NO;
        weakself.canvasView.color = [UIColor blackColor]; //weakself.lastColor;
        weakself.canvasView.lineWidth = weakself.lastLineWidth;
        
    };
    
    self.toolView.eraserBlock = ^{
        weakself.bEraserMode = YES;
        weakself.canvasView.color = [UIColor whiteColor];
        weakself.canvasView.lineWidth = 50;
    };
    
    self.toolView.colorBlock = ^{
        
    };
    
    self.toolView.undoBlock = ^{
        [weakself.canvasView undo];
    };
    
    self.toolView.clearBlock = ^{
        [weakself.canvasView clear];
    };
    
    self.toolView.saveBlock = ^{
        
    };
    
    self.toolView.sliderBlock = ^(CGFloat width) {
        if (!weakself.bEraserMode) {
            weakself.canvasView.lineWidth = width;
        }
        weakself.lastLineWidth = width;
        
    };
}

@property BOOL bEraserMode;
@property UIColor *lastColor;
@property CGFloat lastLineWidth;

#import 
@interface CanvasView : UIView
...
-(void)undo;
-(void)clear;
...
@end

도판을 그리다

    -(ColorView *) colorView {
    if (!_colorView) {
        _colorView = [[ColorView alloc] initWithFrame:self.view.frame];
    }
    return _colorView;
    }

@interface ColorView : UIView
...
@property (nonatomic, copy) void(^selectColorBlock)(UIColor *color);
...
@end

-(ColorView *) colorView {
    if (!_colorView) {
        _colorView = [[ColorView alloc] initWithFrame:self.view.frame];
        __weak typeof (self) weakify = self;
        _colorView.selectColorBlock = ^(UIColor *color) {
            if (!weakify.bEraserMode) {
                weakify.canvasView.color = color;
            }
            weakify.lastColor = color;
        };
    }
    return _colorView;
}

앨범에 저장

    //  info.pkist      
    NSPhotoLibraryUsageDescription
        
    NSPhotoLibraryAddUsageDescription
        
    

//        
#import 
#import 
...
//    block  
self.toolView.saveBlock = ^{
    [weakself saveImageToAlbum:[weakself screenView:weakself.canvasView]];
        
};
...
//   
-(UIImage *) screenView:(UIView *)view {
    CGRect rect = view.frame;
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    [view.layer renderInContext:context];
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}
...
/**
     

 @param image   image
 */
-(void) saveImageToAlbum:(UIImage *)image {
    
    //          
    PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
    if (status == PHAuthorizationStatusDenied || status == PHAuthorizationStatusRestricted) {
        NSLog(@"      ");
    } else {
        UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:),(__bridge void *)self);
        
        
    }
}