Drag UIView without disabling its child controls iPhone/iPad

Question

I have a UIView control (white rectangle in image)

Moreover I am able to drag that control...

And when I press the button I load a subview which is another nib that I created and I placed random controls in it to illustrate my point...

If you guys are interested in finding out how I placed that nib file in that UIView control take a look at this question. I don't thing you have to read it in order to understand my question.

Anyways the problem when loading that nib file is that I can no longer drag the top UIView. Because of this I changed:

for:

in the UIView of the subview. In otherwords the UIView of the nib file that I am placing in the UIView that has the white background.

and when I did that I was able to drag the control but the controls inside the subview no longer works. I have also tried placing the touchesMoved method in the subview instead but when I do that the application behaves strange. Plus the purpose of placing the nib file in a UIView control was to avoid repeating the same drag funcionality on several nib files.

I actually need to create an application like a power point presentation and I need to change the slide as the user slides the UIView and if it's cords are less than x for example then I load the next slide (nib file) in that uiview controller. Maybe there is a simpler way of doing what I need but if I get this drag to work I am done cause I would just have to do that functionality just once.

Answer 1

You should leave the UserInteractionEnabled flag on for your subview if you want it to respond to events.

One way to achieve this would be to do your dragging using a UIGestureRecognizer.

UIPanGestureRecognizer is perfect for this ( UIGestureRecognizer at apple )

Basically you'd attach the gesturerecognizer to the view which you want to pan then adjust it's position in the callbacks it provides.

UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc]
                                      initWithTarget:self action:@selector(handlePanGesture:)];
panGesture.minimumNumberOfTouches = 1;
[draggableSubview addGestureRecognizer:panGesture];
[panGesture release];

Then in the handlePanGesture method you figure out how far the user panned using the translationInView method of the recognizer which it gets passed and translate the subview accordingly.