我正在密切关注此页面http://klanguedoc.hubpages.com/hub/iOS-How-To-Display-Detail-Data-from-UITableView-in-Detail-View-Controller除了最后的组件之外,我几乎可以完美地复制它。准备ForSegue方法。
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
if ([[segue identifier] isEqualToString:@"showDetail"]) {
klViewController *detailViewController = [segue destinationViewController];
detailViewController.treeData = [self.ds objectAtIndex:[self.tableView indexPathForSelectedRow].row];
}
}
我尝试仔细观察并尝试找到其他在线的prepareForSegue方法示例,但它们都指向同一个方向,这意味着该方法和代码是正确的!
xcode 发出的错误是 ARC 问题 - 'NSString' 没有可见的 @interface 声明选择器 'isEqualToString:'
谁能给我指出正确的方向吗?
如果我错了,请纠正我,但是这个prepareForSegue方法应该在tableview类中吗?如果不是,请告诉我,因为我是 xcode 的新手,而且教程有点模糊,因此我担心我错过了解释代码应该去的地方。
提前非常感谢:)
编辑:
SampleData.h
#import <Foundation/Foundation.h>
@interface SampleData : NSObject
@property (nonatomic,strong) NSString * treeName;
@property (nonatomic,strong) NSString * treeDescription;
@end
示例数据.m
#import "SampleData.h"
@implementation SampleData
@synthesize treeName, treeDescription;
@end
SampleDataDOA.h
#import <Foundation/Foundation.h>
#import "SampleData.h"
@interface SampleDataDAO : NSObject
@property (nonatomic,strong) NSMutableArray *someDataArray;
-(NSMutableArray *)PopulateDataSource;
@end
示例数据DOA.m
#import "SampleDataDAO.h"
@implementation SampleDataDAO
@synthesize someDataArray;
-(NSMutableArray *)PopulateDataSource
{
someDataArray= [[NSMutableArray alloc]initWithCapacity:3];
SampleData * mydata= [[SampleData alloc]init];
mydata.treeName = @"Oak";
mydata.treeDescription = @"an oak is a tree or shurb bla bla bla";
[someDataArray addObject:mydata];
mydata=nil;
mydata=[[SampleData alloc]init];
mydata.treeName=@"Douglas Fir";
mydata.treeDescription=@"Douglas Fir are medium-size to extremely large evergreen trees";
[someDataArray addObject:mydata];
mydata=nil;
mydata=[[SampleData alloc]init];
mydata.treeName=@"Sugar Maple";
mydata.treeDescription=@"Sugar Maple is a species of Maple. Sugar Maple is best known for it's sweet leaves as it contain natural sugar and is extremely healthy and beneficial to our health";
[someDataArray addObject:mydata];
mydata=nil;
return someDataArray;
}
@end
TableViewController.h
#import <UIKit/UIKit.h>
#import "SampleDataDAO.h"
#import "SampleData.h"
#import "ViewController.h"
@interface TableViewController : UITableViewController
@property(nonatomic,strong) SampleDataDAO* daoDS;
@property (nonatomic,strong) NSMutableArray *ds;
@end
TableViewController.m(方法prepareForSegue出错)
#import "TableViewController.h"
@interface TableViewController ()
@end
@implementation TableViewController
@synthesize daoDS,ds;
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if( [[segue identifier] isEqualtoString:@"showDetail"]){
ViewController * detailViewController = [segue destinationViewController];
detailViewController.treeData=[self.ds objectAtIndex:[self.tableView indexPathForSelectedRow].row];
}
}
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
daoDS = [[SampleDataDAO alloc]init];
self.ds = daoDS.PopulateDataSource;
// Uncomment the following line to preserve selection between presentations.
// self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// Return the number of rows in the section.
return 3;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"treeCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil){
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// Configure the cell...
SampleData * sample = [self.ds objectAtIndex:indexPath.row];
cell.textLabel.text = sample.treeName;
NSLog(@"Cell Value %d %@", indexPath.row, cell.textLabel.text);
return cell;
}
/*
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the specified item to be editable.
return YES;
}
*/
/*
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (editingStyle == UITableViewCellEditingStyleDelete) {
// Delete the row from the data source
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
}
else if (editingStyle == UITableViewCellEditingStyleInsert) {
// Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
}
}
*/
/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
}
*/
/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the item to be re-orderable.
return YES;
}
*/
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
// Navigation logic may go here. Create and push another view controller.
/*
<#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:@"<#Nib name#>" bundle:nil];
// ...
// Pass the selected object to the new view controller.
[self.navigationController pushViewController:detailViewController animated:YES];
*/
}
@end
ViewController.h
#import <UIKit/UIKit.h>
#import "SampleData.h"
@interface ViewController : UIViewController
@property (strong, nonatomic) IBOutlet UITextView *treeInfo;
@property (nonatomic, strong) SampleData * treeData;
@end
ViewController.m
#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController
@synthesize treeData, treeInfo;
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}
@end
P.S - 代码几乎与网站中的 1 类似,主要区别是我删除了代码的图片部分。
编辑 - 错误日志文件 'NSString' 没有可见的 @interface 声明选择器 'isEqualtoString:' if( [[segue 标识符] isEqualtoString:@"showDetail"]){
错误下划线位于“[[”处,希望这对你们找出真正的错误有帮助._。
最佳答案
首先,改变:
if ([[segue identifier] isEqualToString:@"showDetail"]) {
到
if ([segue.identifier isEqualToString:@"showDetail"]) {
和
klViewController *detailViewController = [segue destinationViewController];
至
klViewController *detailViewController = segue.destinationViewController;
此外,我倾向于将 Segue 连接到 ViewController 或 TableViewController 本身,而不是连接到 tableview 单元格。然后在 cellForRowAtIndexPath 中,我会关闭 segue 并传入 IndexPath,如下所示:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[self performSegueWithIdentifier:@"showDetail" sender:indexPath];
}
然后使用你的prepareForSegue方法我会这样做:
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
if ([segue.identifier isEqualToString:@"showDetail"]) {
// Get the indexPath
NSIndexPath *indexPath = (NSIndexPath *)sender;
klViewController *detailViewController = segue.destinationViewController;
detailViewController.treeData = [self.ds objectAtIndex:indexPath.row;
}
}
关于iphone - iOS 将数据从 tableview 传递到新 View ,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/10828460/