https://dl.dropboxusercontent.com/s/u91qmcqg1tdabv4/stackoverflow-01.png
Like this, but, return will make 0.5 change to 0.
Call this method(use UICollectionViewDelegateFlowLayout):
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
if (_heightIsZero)
return CGSizeMake(320, 0);
else
return CGSizeMake(320, 75);
}
This height is the calculation of pixels and you cannot put pixels in point; they are always numbers 0,1,2,3,4...
Related
I have to display some images in my UICollectionView. In my case, I have 3 different types of image (Square, Portrait, landscape). What I did till now to show the different types of items :
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
UIImage *image = [imageArray objectAtIndex:indexPath.row];
return CGSizeMake(image.size.width, image.size.height);
}
- (UIEdgeInsets)collectionView:(UICollectionView*)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
return UIEdgeInsetsMake(0, 0, 0, 0); // top, left, bottom, right
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
return 0.0;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section
{
return 0;
}
The problem that actually the items are displayed like the image bellow:
But the result wanted is to show the images like a mosaic as the image :
PS: I've tried some frameworks such as : RFQuiltLayout and MosaicLayout but it does not work either (same result as mine).
I believe that I am not the first to have this kind of problem to resolve.
Thank you for your contributions in advance.
Regards
Helo all,
I have create a UIcollectionView cell.I want set the height & width propotional to all devices.For eg.If height 80 & width is 90 on iphone 5s then it should be propotional on other devices as well.I am using this method.
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
return CGSizeMake(80, 90);
}
Try using this
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{
return CGSizeMake(self.view.frame.size.width/.25, self.view.frame.size.width/.28);
}
All you have to do is multiply the dimensions of your cell by whatever proportion you desire. If 80x90 is the size you want on the iPhone 5, then calculate the appropriate multipliers by consulting a guide like this one. For example, the 5's point resolution is 320 x 568, and the 6's is 375 x 667, so your width multiplier will be 375/320, and the height one will be 667/568. (I'll let you do the math. :))
use this
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{
return CGSizeMake(self.view.frame.size.width/2, self.view.frame.size.width/2);
-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section{
return 0
;}
-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section{
return 0; }
I'm using a collection view inside of a static table view cell and I'm using autolayout to define the collection view's frame. Also, I'm using FlowLayout as the collectionViewLayout.
The problem:
The behaviour is just as expected for the iPhone 4s and 5 screen. (same width)
Once the width changes (iPhone 6 and 6 Plus), the collection view resizes properly, but the content keeps it size.
This happens both for the cells and for the sections.
Extra info:
I'm setting collectionViewLayout minimumInteritemSpacingForSectionAtIndex to zero.
The width of the cells is always being set to tableView.frame.size.width / 2
Where I configure the layout:
CGFloat headerHeight = 52;
collectionViewLayout.sectionInset = UIEdgeInsetsMake(0, 0, 0, 0);
collectionViewLayout.headerReferenceSize = CGSizeMake(self.width, headerHeight);
This is what it looks now. The green part represents the UICollectionView. Black and blue the cells. The dividing lines should be resizing and the cells should be divided in 2 columns.
From the code you posted, you are just setting the size for the header but I suppose you also have something like
collectionViewLayout.itemSize = CGSizeMake(self.collectionView.frame.width/2, height);
The important part is in which method you configure this, because if you do it in viewDidLoad the views are not correctly layouted yet so the width would just be the one set in the storyboard, no matter on which device you run your app.
The solution would be to place the code above in viewWillLayoutSubviews
- (void)viewWillLayoutSubviews {
[super viewWillLayoutSubviews];
collectionViewLayout.itemSize = CGSizeMake(self.collectionView.frame.width/2, height);
collectionViewLayout.headerReferenceSize = CGSizeMake(self.collectionView.frame.width/2, height);
}
Another way would be to implement the flowLayout delegate method:
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
return cCGSizeMake(collectionView.frame.width/2, CUSTOM_HEIGHT);
}
// The same for the header
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout referenceSizeForHeaderInSection:(NSInteger)section {
return cCGSizeMake(collectionView.frame.width/2, CUSTOM_HEIGHT);
}
Make sure you set the delegate for the collectionView
Let me know how it goes :)
Update
For the cells, add these methods too:
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
return CGRectZero;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
return 0;
}
As for the sectionHeader, maybe you need to check the constraints you have there, for the separator for example.
Be sure to use all the following for precise styling:
-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView;
-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section;
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath;
-(UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section;
-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section;
-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section;
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath;
-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath;
To change the cell content size, use this:
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
return CGSizeMake((kScreenWidth/2-8), 44); // Use your own X and Y sizes
}
I am attempting to lay my UICollectionView out such that it is a 2x3 grid per page. Here is what I am getting so far:
As you can see, the next "page" is peeping in from the right, which I don't want. I figured if I know my width is always going to be 320pts (iPhone only), then I would want my cells to be 130pts in width with 15pts on either side.
Code for layout delegate:
- (CGSize)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout*)collectionViewLayout
sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
return CGSizeMake(130, 130);
}
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout*)collectionViewLayout
insetForSectionAtIndex:(NSInteger)section {
return UIEdgeInsetsMake(20.0f, 15.0f, 20.0f, 15.0f);
}
And also cellForItemAtIndexPath:
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView
cellForItemAtIndexPath:(NSIndexPath *)indexPath{
CustCollectionViewCell *cell =
[collectionView dequeueReusableCellWithReuseIdentifier:kReuseID
forIndexPath:indexPath];
//Set up list name label
cell.LblListName.font = [self getDefaultFontWithSize:15.0f];
cell.LblListName.textColor = fontAndTertiaryColor;
cell.LblListName.textAlignment = NSTextAlignmentCenter;
cell.LblListName.text = #"Failtron";
//cell.LblListName.adjustsFontSizeToFitWidth = YES;
cell.backgroundColor = secondaryColor;
cell.parallaxIntensity = kParallaxMotion;
[Utilities createViewBorder:cell];
return cell;
}
I thought an inset would act like padding in CSS but I believe I'm off the mark with that one, I should also note that in the UIStoryboard my layout is set to flow. Please let me know if I am missing any relevant code, this is my first attempt with a UICollectionView. I would like this to scroll horizontally as well.
Ok, there are tons of ways to manipulate layouts for a UICollectionView, but sounds like since you are using "flow" you can just implement <UICollectionViewDelegateFlowLayout> in your .h and then use the following methods to tweak your layout to your liking:
#pragma mark – UICollectionViewDelegateFlowLayout
- (CGSize)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout*)collectionViewLayout
sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
// Size of the cell
CGSize retval = CGSizeMake(130,130);
return retval;
}
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout*)collectionViewLayout
insetForSectionAtIndex:(NSInteger)section {
//top, left, bottom, right
return UIEdgeInsetsMake(0, 20, 0, 20);
}
- (CGFloat)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout *)collectionViewLayout
minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
//Minimum spacing between cells
CGFloat interimSpacing = 0.0f;
return interimSpacing;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout *)collectionViewLayout
minimumLineSpacingForSectionAtIndex:(NSInteger)section {
// Minimum spacing between lines. In your case,
this is the distance between columns
// If your scroll direction was vertical,
this would be the distance between rows
CGFloat lineSpacing = 20.0f;
return lineSpacing;
}
I've prepopulated this code with some values that should be pretty darn close to what you wanted to accomplish.
Alternatively, all of this can be done in Interface Builder by selecting the UICollectionView and adjusting the values in the Size Inspector, albeit more confusing in my opinion.
UICollectionView- How to remove spacing above first cell?
I have the top inset = 0, and lines = 10
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{
if (indexPath.row == 0) {
return CGSizeMake(collectionView.width, 44);
}
return CGSizeMake(300, 150);
}
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
return UIEdgeInsetsMake(0, 10, 10, 10);
}
Seems it is something to do with setting the first cell to a different size
if i remove the check for row ==0 in sizeForItemAtIndexPath and return same for all cells it is flush with the top.
Any ideas?
Solution is just to write inside viewDidLoad
self.automaticallyAdjustsScrollViewInsets = NO;
I did it following way (tested on iOS7, 55 is a magic value):
#pragma mark - UICollectionViewDelegateFlowLayout
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout referenceSizeForHeaderInSection:(NSInteger)section
{
//-55 is a tweak value to remove top spacing
return CGSizeMake(1, -55);
}
Alternative way using your code:
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
return UIEdgeInsetsMake(-55, 10, 10, 10);
}
If you'd like to use Interface Builder, you can uncheck "Adjust Scroll View Insets" on the View Controller's Attribute Inspector:
Or use Amit's answer to do it programatically.
I don't think so that one is your top inset. Edit your question with some piece of code you have applied.
If it was collectionView inset then it should remove by passing 0 as top inset.
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
return UIEdgeInsetsMake(0, 10, 10, 10);
}
And the following layout delegate used for row spacing.
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section
{
return 30;
}
Using srtuct and spring set the collectionview autoresizing mask like this and also make sure you set the frame y to 0