在 iOS 中获取 JSON 数据并填充 TableView

Posted 2023-03-15

【中文标题】在 iOS 中获取 JSON 数据并填充 TableView

【英文标题】：Getting JSON data and populate TableView in iOS

【发布时间】：2011-10-08 03:58:56

【问题描述】：

晚上好！

我需要一些帮助。我从 Google Places API 获取一些 JSON 格式的数据，但我没有在 iPad 中填充 TableView（基于拆分视图的应用程序）。我从 ios 开发开始，所以可能有很多错误！我使用了一个项目示例，该示例使用 Twitter API 来检索帖子并只是重命名了 JSON 数据名称。

我有四个文件在项目中使用并实现功能：

SimpleSplitController.h
SimpleSplitController.m
SplitSampleAppDelegate.h
SplitSampleAppDelegate.m

我在 SplitSampleDelegate.m 文件中收到一个错误，因为它在那里进行了检查...

如果有人可以帮助我，我将非常感激！

以下是实现的代码：

SplitSampleAppDelegate.h

#import <UIKit/UIKit.h>

@class APTabBarControllerForSplitController;

@interface SplitSampleAppDelegate : NSObject <UIApplicationDelegate, UITabBarControllerDelegate> 

    NSMutableData *responseData;
    NSMutableArray *tweets;



@property (nonatomic, retain) IBOutlet UIWindow *window;

@property (nonatomic, retain) IBOutlet APTabBarControllerForSplitController *tabBarController;

@property (nonatomic, retain) NSMutableArray *tweets;

@end

SplitSampleAppDelegate.m

#import "SplitSampleAppDelegate.h"
#import "APTabBarControllerForSplitController.h"

@implementation SplitSampleAppDelegate

@synthesize window=_window;

@synthesize tabBarController=_tabBarController;

@synthesize tweets;

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions 

    self.tabBarController.delegate = self;

    // Override point for customization after application launch.
    // Add the tab bar controller's current view as a subview of the window
    // Add the view controller's view to the window and display.
    responseData = [[NSMutableData data] retain];
    tweets = [NSMutableArray array];
    NSURLRequest *request = [NSURLRequest requestWithURL:
                             [NSURL URLWithString:@"https://maps.googleapis.com/maps/api/place/search/json?location=-15.815347,-47.9164097&radius=500&types=restaurant&sensor=true&key=AIzaSyBLY-lBALViJ6ybrgtOqQGhsCDQtsdKsnc"]];
    [[NSURLConnection alloc] initWithRequest:request delegate:self];



    self.window.rootViewController = self.tabBarController;
    [self.window makeKeyAndVisible];
    return YES;


#pragma mark NSURLConnection delegate methods
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response 
    [responseData setLength:0];


- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data 
    [responseData appendData:data];


- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error 


- (void)connectionDidFinishLoading:(NSURLConnection *)connection 
    [connection release];
    NSString *responseString = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
    [responseData release];

    NSDictionary *results = [responseString JSONValue];

    NSMutableArray *allTweets = [results objectForKey:@"results"];

    //This is the part that I get an ERROR
    [viewController setTweets:allTweets];
    [window addSubview:viewController.view];
    [window makeKeyAndVisible];

SimpleSplitController.h

#import <UIKit/UIKit.h>
#import "APSplitViewController.h"
#import <MapKit/MapKit.h>

@interface SimpleSplitController : APSplitViewController 
    NSMutableData *responseData;
    NSArray *tweets;


@property (nonatomic, retain) UIViewController *left;
@property (nonatomic, retain) UIViewController *right;
@property (nonatomic, retain) NSArray *tweets;

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context;

@end

SimpleSplitController.m

#import "SimpleSplitController.h"
#import <QuartzCore/QuartzCore.h>
#import "JSON/JSON.h"
#import "Tweet.h"

@interface SimpleSplitController()
- (UIColor *) randomColor;
- (UIViewController*) randomViewController1;
- (UIViewController*) randomViewController2;
- (UIViewController*) randomViewController3;
- (void) buttonPushRandomViewController1;
- (void) buttonPushRandomViewController2;

@end

@implementation SimpleSplitController

@synthesize left, right;

@synthesize tweets;

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 

    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) 
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
    

    // Configure the cell...

    NSDictionary *aTweet = [tweets objectAtIndex:[indexPath row]];

    cell.textLabel.text = [aTweet objectForKey:@"name"];
    cell.textLabel.adjustsFontSizeToFitWidth = YES;
    cell.textLabel.font = [UIFont systemFontOfSize:12];
    cell.textLabel.minimumFontSize = 10;
    cell.textLabel.numberOfLines = 4;
    cell.textLabel.lineBreakMode = UILineBreakModeWordWrap;

    cell.detailTextLabel.text = [aTweet objectForKey:@"vicinity"];

    NSURL *url = [NSURL URLWithString:[aTweet objectForKey:@"icon"]];
    NSData *data = [NSData dataWithContentsOfURL:url];
    cell.imageView.image = [UIImage imageWithData:data];
    cell.selectionStyle = UITableViewCellSelectionStyleNone;
    return cell;

【参考方案1】：

你可能在这里错了。您正在检查对象，而不是值。

 NSMutableArray *allTweets = [results valueForKey:@"results"];

你的问题已经解决了。