How will i remove UIBezierPath from the uiview on button click.? - ios

Question

I am working on digital signature on uiview. i create it normaly by this code, but i am not able to remove bezier path on button click.i am sharing my code PLease look at my code.
#import "Signature.h"
#implementation Signature {
UIBezierPath *path;
UIImage *incrementalImage;
CGPoint pts[5]; // we now need to keep track of the four points of a Bezier segment and the first control point of the next segment
uint ctr;
}
- (id)initWithCoder:(NSCoder *)aDecoder
{
if (self = [super initWithCoder:aDecoder])
{
[self setMultipleTouchEnabled:NO];
[self setBackgroundColor:[UIColor greenColor]];
path = [UIBezierPath bezierPath];
[path setLineWidth:2.0];
}
return self;
}
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self setMultipleTouchEnabled:NO];
path = [UIBezierPath bezierPath];
[path setLineWidth:2.0];
}
return self;
}
- (void)drawRect:(CGRect)rect
{
[incrementalImage drawInRect:rect];
[path stroke];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
ctr = 0;
UITouch *touch = [touches anyObject];
pts[0] = [touch locationInView:self];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint p = [touch locationInView:self];
ctr++;
pts[ctr] = p;
if (ctr == 4)
{
pts[3] = CGPointMake((pts[2].x + pts[4].x)/2.0, (pts[2].y + pts[4].y)/2.0); // move the endpoint to the middle of the line joining the second control point of the first Bezier segment and the first control point of the second Bezier segment
[path moveToPoint:pts[0]];
[path addCurveToPoint:pts[3] controlPoint1:pts[1] controlPoint2:pts[2]]; // add a cubic Bezier from pt[0] to pt[3], with control points pt[1] and pt[2]
[self setNeedsDisplay];
// replace points and get ready to handle the next segment
pts[0] = pts[3];
pts[1] = pts[4];
ctr = 1;
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
[self drawBitmap];
[self setNeedsDisplay];
[path removeAllPoints];
ctr = 0;
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"hello");
[self touchesEnded:touches withEvent:event];
}
- (void)drawBitmap
{
UIGraphicsBeginImageContextWithOptions(self.bounds.size, YES, 0.0);
if (!incrementalImage) // first time; paint background white
{
UIBezierPath *rectpath = [UIBezierPath bezierPathWithRect:self.bounds];
[[UIColor greenColor] setFill];
[rectpath fill];
}
[incrementalImage drawAtPoint:CGPointZero];
[[UIColor blackColor] setStroke];
[path stroke];
incrementalImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
}
- (void)erase {
NSLog(#"Erase Testing...");
// self->path = nil; //Set current path nil
//path = [UIBezierPath bezierPath];
// [self setNeedsDisplay];
}
I call erase method on unbutton click from another class, but I am not able to remove uibezeripath.

Answer 1

Try using this to remove the UIBezierPath,
[path removeAllPoints];
If you use CAShapeLayer *rectLayer = [[CAShapeLayer alloc] init]; aswell then call this line too,
[rectLayer removeFromSuperlayer];

Answer 2

Check how i am using this in one of my project if it can help,
- (void)drawRect:(CGRect)rect {
[_path stroke];
}
- (id)initWithFrame:(CGRect)frame{
self = [super initWithFrame: frame];
if (self) {
// set Multiple touches Enabled to false for allow only single touch.
[self setMultipleTouchEnabled: NO];
_path = [UIBezierPath bezierPath];
// set Line width.
[_path setLineWidth:2.0];
}
return self;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
isMouseswipped = NO; //for touches eneded to make dot
ctr = 0;
UITouch *myTouch = [touches anyObject];
pts[0] = [myTouch locationInView: self];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
isMouseswipped = YES; //for touches eneded to make dot
CustomSignatureViewController *csvc = [[CustomSignatureViewController alloc]init];
UITouch *touch = [touches anyObject];
CGPoint p = [touch locationInView: self];
ctr++;
pts[ctr] = p;
if (ctr == 4) {
pts[3] = CGPointMake((pts[2].x + pts[4].x)/2.0, (pts[2].y + pts[4].y)/2.0);
[_path moveToPoint: pts[0]];
[_path addCurveToPoint: pts[3] controlPoint1:pts[1] controlPoint2:pts[2]];
[self setNeedsDisplay];
pts[0] = pts[3];
pts[1] = pts[4];
ctr = 1;
csvc.status = 1;
self.status = 1;
}
}
- (void)erase {
_path = nil;
_path = [UIBezierPath bezierPath];
[_path setLineWidth:2.0];
[self setNeedsDisplay];
}
This is custom class which returns uiview to fraw signature. It is subclass of UIView.
So when required signature, i import this class and instantiate it and got uiview object on which i can draw. then capture that view as image using graphics beginimage context!
Update :
In viewcontroller i am calling method like,
-(void)clear : (id)sender{
[signView erase];
signView.status = 0;
}
signView is signature class(as mentioned above)'s object. and erase is public method declared in .h file of signature class. (note : signature class is subclass of uiview so intance of it returns view onject so signView is uiview object)
Hope this will help :)

Answer 3

use this code it will help you
- (void)resetPath {
path = nil;
path = [UIBezierPath bezierPath];
[self setNeedsDisplay];
}
create this method in .h file of your subclass. From your UIViewController class you call this method whenever you need it
- (IBAction)youraction:(id)sender
{
[self.subclassedView resetPath];
}