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iOS

Posted by Junaid Abd
Junaid Abd
Courses Plus Student 32 Points

Create 'gravity' that affect buttons?

How do I create 'gravity' in my all so when a button is pressed the rest of the buttons will fall to the bottom if the screen. Also how can I have one or two buttons which are immune to this?

Language- Swift

David Marinez
David Marinez
2,610 Points

You can add "UIGravityBehavior" to all buttons you want to fall. If you want them to have collision with the screen you need to add "UICollisionBehavior". You can do something like this:

@interface yourClass() @property (strong, nonatomic) UIDynamicAnimator *animator; @end

-(void) animateButton: (UIButton *) button toFall: (BOOL) fallingDown withMagnitud: (CGFloat) magnitude { [self.animator removeAllBehaviors];

[self getFrameFromButton:button];

UIGravityBehavior *gravity = [[UIGravityBehavior alloc] initWithItems:@[button]];

UICollisionBehavior *collision = [[UICollisionBehavior alloc] initWithItems:@[button]];

UIDynamicItemBehavior *behavior = [[UIDynamicItemBehavior alloc] initWithItems:@[button]];

[behavior setResistance:1];

[self.animator addBehavior:behavior];

[collision setTranslatesReferenceBoundsIntoBoundary:YES];

collision.collisionDelegate = self.delegate;

collision.collisionMode = UICollisionBehaviorModeEverything;

[gravity setGravityDirection:CGVectorMake(0, 100)];

[gravity setMagnitude:5];

[self.animator addBehavior:gravity];

[self.animator addBehavior:collision];

}