Question

I have a UIControl subclass which follows the UIAccessibilityContainer informal protocol: it returns NO to -isAccessibilityElement, delivers the correct -accessibilityElementCount and elements in the accessors.

Each UIAccessibilityElement which is created to represent an accessibility region is created successfully, and the frame is a 1:1 mapping of another CGRect I’m drawing.

E.g., I’m drawing into {94, 99}, {209, 350}} and the -accessibilityFrame on the UIAccessibilityElement is set to the same CGRect value.

However, when in landscape (or upside-down portrait) orientation, the frames (only for accessibility elements, drawing still works fine) are rotated incorrectly. The top-left point relative to the frame is always the corner top-left of the home button.

Here’s a screenshot from the simulator:

As you can see, it’s in landscape mode, and the frame is totally impossibly not what it’s specifying.

Here’s the code driving the creation of the elements:

CGRect localRect = someCGRectVariable;
CGRect globalRect = CGRectOffset(localRect, CGRectGetMinX(self.accessibilityFrame), CGRectGetMinY(self.accessibilityFrame));

UIAccessibilityElement *accElem = [[UIAccessibilityElement alloc]initWithAccessibilityContainer:self];

accElem.isAccessibilityElement = YES;
accElem.accessibilityFrame = globalRect;
accElem.accessibilityHint = [NSString stringWithFormat:NSLocalizedString(@"xyz %@", nil), someName];
accElem.accessibilityTraits = UIAccessibilityTraitButton;
accElem.accessibilityLabel = nameValue;

It looks to me like the rotation is busted, but I can’t put my finger on it. It’s worth noting that it works perfectly fine in portrait mode.

Answer 1

accessibilityFrame returns its answer in screen coordinates, without adjusting for device rotation.

Somewhere in Apple’s docs it suggests you use [UIWindow convertRect:toWindow:] in this sort of case.