旋转时UICollectionView不适配iPad屏幕

Question

#pragma mark Rotation handling methods

-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:
(NSTimeInterval)duration {
NSLog(@"IS ROTATING");
// Fade the collectionView out
[self.collectionView setAlpha:0.0f];

// Suppress the layout errors by invalidating the layout
[self.collectionView.collectionViewLayout invalidateLayout];

// Calculate the index of the item that the collectionView is currently displaying
CGPoint currentOffset = [self.collectionView contentOffset];
self.currentIndex = currentOffset.x / self.collectionView.frame.size.width;
}

- (void)viewWillLayoutSubviews;
{
[super viewWillLayoutSubviews];
UICollectionViewFlowLayout *flowLayout = (id)self.collectionView.collectionViewLayout;

if (UIDeviceOrientationIsLandscape([[UIApplication sharedApplication] statusBarOrientation])) {
    flowLayout.itemSize = CGSizeMake(self.view.bounds.size.width, self.view.bounds.size.height);
} else {
    flowLayout.itemSize = CGSizeMake(self.view.bounds.size.width, self.view.bounds.size.height);
}

[flowLayout invalidateLayout]; //force the elements to get laid out again with the new size
}


-(void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation {

// Force realignment of cell being displayed
CGSize currentSize = self.view.bounds.size;
float offset = self.currentIndex * currentSize.width;
[self.collectionView setContentOffset:CGPointMake(offset, 0)];


NSLog(@"CURRENT bounds: %f",self.view.bounds.size.width);
NSIndexPath *indexPath = [NSIndexPath indexPathForItem:self.currentIndex inSection:0];
[self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:UICollectionViewScrollPositionLeft animated:NO];


// Fade the collectionView back in
[UIView animateWithDuration:0.125f animations:^{
    [self.collectionView setAlpha:1.0f];
}];


}

这就是代码。我只想图像保持全屏和集合视图是符合肖像。我可以看到单元格正在尝试调整，但是集合视图本身并没有调整大小。有什么建议/修复方法吗？

Answer 1

您在何处设置collectionView的新帧？您可以在willAnimateRotationToInterfaceOrientation: duration:或didRotateFromInterfaceOrientation:中设置它，或者如果它等于superview的大小，则将大小调整蒙版设置为灵活的宽度或高度。

_collectionView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;

在viewWillLayoutSubviews中，您将itemSize设置为横向和纵向相同，这是有意的吗？