I want to determine whether the tapped location is in region or not. I have 4 CGPoints and I know this can be done by using UITouch. Also, I have screen tapped location by using the function
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *myTouch = [[touches allObjects] objectAtIndex: 0];
CGPoint currentPos = [myTouch locationInView:self.view];
}
And for example my 4 CGPoints are
self.firstPoint = CGPointMake(50.0f, 50.0f);
self.secondPoint = CGPointMake(200.0, 50.0);
self.thirdPoint = CGPointMake(200.0, 200.0);
self.fourthPoint = CGPointMake(50.0, 120.0);
Thanks in advance
You should use a CGRect to represent the rect instead of four CGPoints and then use CGRectContainsPoint() to check if the rect contains the point.
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
CGPoint location = [touch locationInView:touch.view];
image=[UIImage imageNamed:#"anyImage.gif"];
newView = [[UIImageView alloc]initWithImage:image];
if (location.y<480|| location.y>50)
{
//write your code
}
}
Related
How can I move CGRect with uitouches? If anyone has idea please explain.
if(areaSelected)
return;
UITouch *mytouch=[[touches allObjects] objectAtIndex:0];
[myPath addLineToPoint:[mytouch locationInView:self]];
[self setNeedsDisplay];
Hi as per my understanding you need to move the cropped image to one place to other place so you need to code it in the touches stuff...
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
CGPoint location = [touch locationInView:touch.view];
cloud.center = location;
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
[self touchesBegan:touches withEvent:event];
}
Here cloud is the UIImageView you can make it as cropped image ....
cloud.image=croppedImage; //[you must assign this first...]
i hope it helps you...
You need to reset the frame of the rectangle:
[cropRect setFrame:CGRectMake(<new x coordinate>, <new y coordinate>, width, height)]
For various reasons, I've moved these methods from a UIView subclass to my viewcontroller. And I finally got it working, except for one thing. Not only am I able to drag the UIImageviews I've programmatically created, but the actual view controllers view is draggable too. Creating this much undesired effect. I guess it's the fact that it's touches anyobject, and the background itself is an object. I'm just not sure how exclude the background. I would think that it would need the "UserInteraction enabled", but I guess not? I only want it to make UIImageViews draggable. Please forgive my noobness. I'm still learning.
I have all the imageviews i'd want "touchable" in an NSMutableDictionary called "letterDictionary". Would it be possible to only have touch apply to what's in the dictionary?
http://imgur.com/W08dI
- (void) touchesBegan:(NSSet*)touches withEvent:(UIEvent*)event {
UITouch *touch = [touches anyObject];
touchPoint = [touch locationInView:self.view];
movingLetter = [touch view];
CGPoint pointInside = [touch locationInView:[touch view]];
if ([movingLetter pointInside:pointInside withEvent:event]) touchedInside = YES;
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
if (touchedInside) {
UITouch *touch = [touches anyObject];
CGPoint newPoint = [touch locationInView:self.view]; // get the new touch location
movingLetter.center = CGPointMake(movingLetter.center.x + newPoint.x - touchPoint.x, movingLetter.center.y + newPoint.y - touchPoint.y);
touchPoint = newPoint;
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
if (touchedInside) {
UITouch *touch = [touches anyObject];
CGPoint newPoint = [touch locationInView:self.view];
movingLetter.center = CGPointMake(movingLetter.center.x + newPoint.x - touchPoint.x, movingLetter.center.y + newPoint.y - touchPoint.y);
if (CGRectIntersectsRect([movingLetter frame], [placeHolder frame]))
{
movingLetter.center = placeHolder.center;
}
}
touchedInside = NO;
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
touchedInside = NO;
}
You have the view that was touched,
UITouch *touch = [touches anyObject];
touchPoint = [touch locationInView:self.view];
movingLetter = [touch view];
just test to see if it is the class you are looking for (e.g. a UIImageView) then return
UITouch *touch = [touches anyObject];
if (![[touch view] isKindOfClass:[UIImageView class]])
{
return;
}
In this touchesBegen Method :
-(void)touchesBegan:(NSSet* )touches withEvent:(UIEvent *)event
{
[self.view endEditing:YES];
UITouch *touch = [touches anyObject];
_previousPoint1 = [touch previousLocationInView:self.main_uiview];
_previousPoint2 = [touch previousLocationInView:self.main_uiview];
_currentPoint = [touch locationInView:self.main_uiview];
[self touchesMoved:touches withEvent:event];
self.bezierPath = [UIBezierPath bezierPath];
[self.bezierPath moveToPoint:_currentPoint];
}
TouchesMove Method
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent* )event
{
UITouch *touch = [touches anyObject];
_previousPoint2 = _previousPoint1;
_previousPoint1 = [touch previousLocationInView:self.main_uiview];
_currentPoint = [touch locationInView:self.main_uiview];
lastPoint = _currentPoint;
[_bezierPath addLineToPoint:lastPoint];
// calculate mid point
CGPoint mid1 = midPoint4(_previousPoint1, _previousPoint2);
CGPoint mid2 = midPoint4(_currentPoint, _previousPoint1);
UIGraphicsBeginImageContextWithOptions(self.bg_imageview.frame.size, NO, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(context,brush);
CGContextSetLineCap(context, kCGLineCapRound);
CGContextSetLineJoin(context,kCGLineJoinRound);
[self.bg_imageview.image drawInRect:CGRectMake(0, 0, self.bg_imageview.frame.size.width, self.bg_imageview.frame.size.height)];
CGContextMoveToPoint(context, mid1.x, mid1.y);
// Use QuadCurve is the key
CGContextAddQuadCurveToPoint(context, _previousPoint1.x, _previousPoint1.y, mid2.x, mid2.y);
CGContextSetLineCap(context, kCGLineCapRound);
CGContextSetStrokeColorWithColor(context,[UIColor blackColor].CGColor);
CGContextSetLineWidth(context, 3.0);
CGContextStrokePath(context);
self.bg_imageview.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();}
I'm making a simple dial that rotates as you drag your finger across it. It rotates great, but it also rotates when i touch anywhere on the screen and drag my finger.
How can i restrict the first touches to be only inside my imageview object? or where am i going wrong?
this is my code of trouble:
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
UIImage *image1 = [UIImage imageNamed:#"nav#2x.png"];
wheelfrom = [[UIImageView alloc] initWithImage:image1];
wheelfrom.frame =CGRectMake(10, -130, 300, 300);
[self addSubview:wheelfrom];
}
return self;
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch =[[[event allTouches] allObjects] lastObject];
firstLoc = [touch locationInView:self];
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch =[[[event allTouches] allObjects] lastObject];
CGPoint curLoc = [touch locationInView:self];
float fromAngle = atan2( firstLoc.y-wheelfrom.center.y,
firstLoc.x-wheelfrom.center.x );
float toAngle = atan2( curLoc.y-wheelfrom.center.y,
curLoc.x-wheelfrom.center.x );
float newAngle = angle + (toAngle - fromAngle);
CGAffineTransform cgaRotate = CGAffineTransformMakeRotation(newAngle);
wheelfrom.transform = cgaRotate;
angle = newAngle;
}
Thanks for your help!
You try like this,
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [[event allTouches] anyObject];
CGPoint location = [touch locationInView:self.view];
if(CGRectContainsPoint(wheelfrom.frame, location))
{
//do your things
}
}
You can try by checking if the point of touch is within the frame of the image view.Do what you want only if its yes.
Inside -(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event, check the firstLoc is within your range.
Is it possible to drag UIView around the iOS screen while it has both image and text? e.g. small cards. Could you point me to the similar (solved) topic? I haven't found any.
This is what a neat solution, based on pepouze's answer, would look like (tested, it works!)
- (void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *aTouch = [touches anyObject];
CGPoint location = [aTouch locationInView:self];
CGPoint previousLocation = [aTouch previousLocationInView:self];
self.frame = CGRectOffset(self.frame, (location.x - previousLocation.x), (location.y - previousLocation.y));
}
While UIView does not have a built-in support for moving itself along the user dragging, it should be not so difficult to implement it. It is even easier when you are only dealing with dragging on the view, and not other actions such as tapping, double tapping, multi-touches etc.
First thing to do is to make a custom view, say DraggableView, by subclassing UIView. Then override UIView's touchesMoved:withEvent: method, and you can get a current dragging location there, and move the DraggableView. Look at the following example.
-(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *aTouch = [touches anyObject];
CGPoint location = [aTouch locationInView:self.superview];
[UIView beginAnimations:#"Dragging A DraggableView" context:nil];
self.frame = CGRectMake(location.x, location.y,
self.frame.size.width, self.frame.size.height);
[UIView commitAnimations];
}
And because all subviews of the DraggableView object will be moved, too. So put all your images and texts as subviews of the DraggableView object.
What I implemented here is very simple. However, if you want more complex behaviors for the dragging, (for example, the user have to tap on the view for a few seconds to move the view), then you will have to override other event handling methods (touchesBegan:withEvent: and touchesEnd:withEvent) as well.
An addition to MHC's answer.
If you don't want the upper left corner of the view
to jump under your finger, you can also override touchesBegan
like this:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *aTouch = [touches anyObject];
offset = [aTouch locationInView: self];
}
and change MHC's touchesMoved to:
-(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *aTouch = [touches anyObject];
CGPoint location = [aTouch locationInView:self.superview];
[UIView beginAnimations:#"Dragging A DraggableView" context:nil];
self.frame = CGRectMake(location.x-offset.x, location.y-offset.y,
self.frame.size.width, self.frame.size.height);
[UIView commitAnimations];
}
you should also define CGPoint offset in the interface:
#interface DraggableView : UIView
{
CGPoint offset;
}
EDIT:
Arie Litovsky provides more elegant solution that allows you to ditch the ivar: https://stackoverflow.com/a/10378382/653513
Even though rokjarc solution works, using
CGPoint previousLocation = [aTouch previousLocationInView:self.superview];
avoids the CGPoint offset creation and the call to touchesBegan:withEvent:
Here is a solution to drag a custom UIView (it can be scaled or rotated through its transform), which can hold images and/or text (just edit the Tile.xib as required):
- (void) touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event
{
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView:self];
CGPoint previous = [touch previousLocationInView:self];
if (!CGAffineTransformIsIdentity(self.transform)) {
location = CGPointApplyAffineTransform(location, self.transform);
previous = CGPointApplyAffineTransform(previous, self.transform);
}
self.frame = CGRectOffset(self.frame,
(location.x - previous.x),
(location.y - previous.y));
}
This work for me. My UIView rotated and scaled
- (void) touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView:self];
CGPoint previous = [touch previousLocationInView:self];
if (!CGAffineTransformIsIdentity(self.transform)) {
location = CGPointApplyAffineTransform(location, self.transform);
previous = CGPointApplyAffineTransform(previous, self.transform);
}
CGRect newFrame = CGRectOffset(self.frame,
(location.x - previous.x),
(location.y - previous.y));
float x = CGRectGetMidX(newFrame);
float y = CGRectGetMidY(newFrame);
self.center = CGPointMake(x, y);
}
I am working on a app and i want to move a UIImage in the Y axis only, not in Xaxis, here's what i did till now
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
stretchPoint = [[touches anyObject]locationInView:self.view];
arrowImage.center = stretchPoint;
}
The above code is moving the arrowImage in both the axis,
stretchPoint is an instance of CGPoint, My app is in portrait mode, can anyone give me a basic idea to how to do this, as the arrowImage is a instance of UIImageView.
this should work fine:
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint currentPoint = [touch locationInView:self.view];
currentPoint.x = arrowImage.center.x;
arrowImage.center = currentPoint;
}
Subclass the UIImage and implement the following code
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint currentPoint = [touch locationInView:[self superview]];
CGPoint newCenter = CGPointMake(self.center.x, currentPoint.y);
self.center = newCenter;
}
I am not sure as have not tested,but you can implement something like this :
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint currentPoint = [touch locationInView:self.view];
currentPoint.y = 20;
}
Something like:
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
stretchPoint = [[touches anyObject] locationInView:self.view];
arrowImage.frame = CGPointMake(arrowImage.origin.x,
stretchPoint.y,
arrowImage.size.width,
arrowImage.size.height);
}