Use of IOS Uicollectionview (create UI in code)

Adding CollectionView to the controller

Initialize the CollectionView in the Viewdidload method of the Controller

static NSString *id = @ "Collectionviewcell";

-(void) Viewdidload {

[Super Viewdidload];

//Uicollectionview *collectionview = [[Uicollectionview alloc]initwithframe:self.view.bounds]; This initialization method cannot be compiled by

Uicollectionview *collectionview = [[Uicollectionview alloc]initwithframe:self.view.bounds collectionViewLayout:[[  Uicollectionviewflowlayout Alloc]init]]; //Do not use uicollectionviewlayout,uicollectionviewlayout here is the abstract base class, is dedicated to subclass inheritance; Uicollectionviewflowlayout is the most basic layout.

Collectionview.datasource = self;

Collectionview.delegate = self;

[Self.view Addsubview:collectionview];

　A Collectionviewcell is typically customized because the system is prefabricated collectionviewcell, unlike Tableviewcell, which has Label,imageview, Collectionviewcell only 2 View:backgroundview and Selectedbackgroundview

[CollectionView registerclass:[Customcell class] Forcellwithreuseidentifier:id];

}

#pragma mark-collectionviewdatasource

-(Nsinteger) Numberofsectionsincollectionview: (Uicollectionview *) CollectionView

{

return 1; //As with TableView

}

-(Nsinteger) CollectionView: (Uicollectionview *) CollectionView numberofitemsinsection: (NSInteger) Section

{

return self.photos.count; //As with TableView

}

-(Uicollectionviewcell *) CollectionView: (Uicollectionview *) CollectionView Cellforitematindexpath: (NSIndexPath *) Indexpath

{

Customcell *cell = (Customcell *) [CollectionView dequeuereusablecellwithreuseidentifier:id ForIndexPath:indexPath];

//Do not need to write if (!cell) {initialize cell;}

///Indexpath.row, may collectionview layout more free, not like TableView is generally "line", so more people like to use Indexpath.item bar

[Cell.imagev setimage:[uiimage Imagenamed:self.photos[indexpath. Item]];

return cell;

}

Custom Collectionviewcell

CustomCell.h

@interface Customcell:uicollectionviewcell

@property (nonatomic, weak) Uiimageview *imagev;

@end

customcell.m

-(ID) initWithFrame: (CGRect) frame

{

self = [super Initwithframe:frame];

if (self) {

Uiimageview *imageview = [[Uiimageview alloc]init];

Imageview.frame = CGRectMake (5, 5, 40, 40);

[Self addsubview:imageview];

_imagev = ImageView;

}

return self;

}

Use of IOS Uicollectionview (create UI in code)