How to animate imageview from off screen

Question

I have an imageview I put onto the view controller of a circle.

I would like to start that circle from off screen and move it to the location I've put it.

What would be the best way to animate it?

Answer 1

Try this;

-(void)viewWillAppear {
    [UIView animateWithDuration:5
                          delay:5
                        options:UIViewAnimationOptionCurveEaseOut
                     animations:^{
                             CGRect frame = view.frame;
                             frame.origin.y = self.view.frame.size.height-200;
                             frame.origin.x = 0;
                             view.frame = frame;
                         }completion:^(BOOL finished) {}];
}

You many animation option's [UIViewAnimationOptions]

    UIViewAnimationOptionCurveEaseInOut,
    UIViewAnimationOptionCurveLinear,
    UIViewAnimationOptionTransitionFlipFromLeft,
    UIViewAnimationOptionTransitionCurlUp,
    UIViewAnimationOptionTransitionCrossDissolve,
    UIViewAnimationOptionTransitionFlipFromTop..

Answer 2

You want to create your image view off-screen. Its easiest if you set it up in Interface Builder that way. you can create it on-screen, add a constraint to place it at the target location, note the value, and then change the constraint's constant so the view is moved off-screen.

Then control-drag the constraint into your view controller and create an outlet to it.

To animate the image view on-screen, change the constraint's constant value to the "on-screen" value you noted above, and then call layoutIfNeeded() on the view from inside an a UIView animateWithDuration block.

If you want to add the image view in code then you need to add it off-screen, add it as a subview, and then trigger a UIView animation to move it back on-screen. You should probably also do the positioning with constraints as outlined above, although it gets more complicated because you have to create those constraints in code.