无法访问集合视图单元格信息

Question

您好，我正在尝试通过 UIsegmentedcontrol 访问 UICollection 视图单元格信息。

在集合视图中，我有四个标签和 UIsegmented control.When我点击分段控件，我想显示标签值。

这是我的代码。

- (UIView *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
CollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"CELL" forIndexPath:indexPath];
cell.mySegmentedControl.tag = indexPath.row;
selectedSegment = cell.mySegmentedControl.selectedSegmentIndex;
[cell.mySegmentedControl addTarget:self action:@selector(segmentValueChanged:) forControlEvents:UIControlEventValueChanged];
cell.caseid.text=[tmpDict objectForKey:@"CaseId"];
caseid = [tmpDict objectForKey:@"CaseId"];
}

- (void) segmentValueChanged: (UISegmentedControl *) sender {
//NSInteger index = sender.tag;
if(sender.selectedSegmentIndex == 0)
{
 NSString *localcaseid = caseid; // it shows default value may be first cell value.
CollectionViewCell * cell = [[CollectionViewCell alloc]init];
NSString *localcaseid = cell.caseid.text; //it prints null value
}
else
{
}

以上代码不适用于 me.any 帮助 appreciated.I 想要显示该特定单元格的信息。

Answer 1

    if(sender.selectedSegmentIndex == 0) {
        NSString *localcaseid = caseid;
        NSIndexPath *tempIndexPath = [NSIndexPath indexPathForRow:sender.tag inSection:0];
        CollectionViewCell *cell = (CollectionViewCell *)[CollectionView cellForItemAtIndexPath:tempIndexPath];
        NSString *localcaseid = cell.caseid.text;
        NSLog(@"%@",localcaseid);
    }
    else {
    }

Answer 2

// CustomCell.h

#import <UIKit/UIKit.h>
@protocol CollectionViewCellDelegate;

@interface CustomCollectionViewCell : UICollectionViewCell

@property(weak, nonatomic) id<CollectionViewCellDelegate> delegate;

@end

// CustomCell.m

#import "CollectionViewCell.h"

// Create your delegate
@protocol CollectionViewCellDelegate <NSObject>
- (void)collectionViewCell:(CustomCollectionViewCell *)cell segmentedControlChangedValue:(UISegmentedControl *)control;
@end

@implementation CustomCollectionViewCell

// Implement this delegate call on the cell, not on the viewController
- (void) segmentValueChanged: (UISegmentedControl *) sender {
    // Call your delegate with the cell added as parameter
    [self.delegate collectionViewCell:self segmentedControlChangedValue:sender];
}

@end

在您的 viewcontroller 中，确保它正在向委托人确认，在您的 viewController 声明旁边添加 <CollectionViewCellDelegate> 并导入单元格头文件。

// ViewController.h

#import "CustomCollectionViewCell.h"

@interface ViewController : UIViewController <CollectionViewCellDelegate>

// ViewController.m

// 将cellForItem中的delegate分配给你VC

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
    // create your cell
    // assign your cell's delegate to self
    cell.delegate = self
}

    // Declare the delegate method on the viewController
    - (void)collectionViewCell:(CustomCollectionViewCell *)cell segmentedControlChangedValue:(UISegmentedControl *)control {
        // here you now have access to the cell, where the segmented was pressed in
        // Do what you need to and make sure you reload the data at the end of this function, when you have set up your cell

        [self.collectionView reloadData];
    }

无法访问集合视图单元格信息

Unable to access UICollection view cell infromation

xcode

objective-c

ios

uicollectionview

uicollectionviewcell