iOS从.plist文件加载数据

Question

我是iOS开发的新手。 目前，我正在尝试从.plist文件中获取数据并显示在UITableView上 。 在运行应用程序时，Xcode没有提供任何错误，但是我的应用程序除了显示此内容外，什么都没有显示

这是我的代码

TestAppTableViewController.h

#import <UIKit/UIKit.h>

@interface TestAppTableViewController : UITableViewController

@property (nonatomic,strong) NSArray *content;

@end 

TestAppTableViewController.m

#import "TestAppTableViewController.h"

@interface TestAppTableViewController ()

@end

@implementation TestAppTableViewController

@synthesize content = _content;

- (NSArray *) content{
    if (!_content) {
        _content = [[NSArray alloc]initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"Data" ofType:@"plist"]];
    }

    return _content;
}

- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    // 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)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{

    // Return the number of sections.
    return 0;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    return [self.content count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    // Configure the cell...

    cell.textLabel.text = [[self.content objectAtIndex:indexPath.row]valueForKey:@"city"];
    cell.detailTextLabel.text = [[self.content objectAtIndex:indexPath.row]valueForKey:@"state"];
    return cell;
}

Data.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<array>
    <dict>
        <key>city</key>
        <string>New York</string>
        <key>state</key>
        <string>NY</string>
        <key>cityText</key>
        <string>This is the description of the city that goes in the tex view just testing.</string>
    </dict>
    <dict>
        <key>city</key>
        <string>Los Angeles</string>
        <key>state</key>
        <string>CA</string>
        <key>cityText</key>
        <string>This the second item&apos;s textview</string>
    </dict>
    <dict>
        <key>city</key>
        <string>Chicago</string>
        <key>state</key>
        <string>IL</string>
        <key>cityText</key>
        <string>here is the text view description for the third item.</string>
    </dict>
    <dict>
        <key>city</key>
        <string>Sandiago</string>
        <key>state</key>
        <string>CA</string>
        <key>cityText</key>
        <string>Here is another city from california</string>
    </dict>
    <dict>
        <key>city</key>
        <string>Talahasy</string>
        <key>state</key>
        <string>FL</string>
        <key>cityText</key>
        <string>Talahasy is the capital of the florida state.</string>
    </dict>
    <dict>
        <key>city</key>
        <string>Boise</string>
        <key>state</key>
        <string>Idaho</string>
        <key>cityText</key>
        <string>boise is the capital of idaho and i have no idea where that is.</string>
    </dict>
</array>
</plist>

我无法找出问题所在。 那么，我的问题是代码中的问题是什么？ 如何显示plist文件中的数据？ 我浏览了上一个问题的stackoverflow，但这并没有帮助我。

Answer 1

您的表视图至少需要一个部分-

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
    {

    // Return the number of sections.
    return 1;// make this 1
}

还可以尝试像这样使用objectForKey代替（尽管根据文档说明，如果键不是以@开头，它会自动调用）并输入强制类型转换。

cell.textLabel.text = (NSString*)[[self.content objectAtIndex:indexPath.row] objectForKey:@"city"];
cell.detailTextLabel.text = (NSString*)[[self.content objectAtIndex:indexPath.row] objectForKey:@"state"];

如果您仍然一无所获，那么值得检查一下内容实际上是否包含plist数据。 在您的-（NSArray *）content方法中 ，返回之前可能值得记录_content的计数。 还要确认self.content = _content

Answer 2

我认为问题出在这里，您应该返回1或除0以外的任何数字：

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{

    // Return the number of sections.
    return 0;
}

Answer 3

@interface ViewController:UIViewController <UITableViewDelegate, UITableDataSource>

只要看到您的plist，您就可以使用字典了。 所以像下面的代码一样实现，可以帮助您

- (void)viewDidLoad {

    tableView.delegate = self;
    tableView.dataSource = self;

    NSString *path = [[NSBundle mainBundle] pathForResource:@"yourFilename" ofType:@"plist"];
    NSArray *contentArray = [NSArray arrayWithContentsOfFile:path];
    // Having outlet for tableArray variable.
    tableArray = [[NSMutableArray alloc]initWithArray:contentArray copyItems:YES];

    [super viewDidLoad];

}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return [tableArray count];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
   // In your case dictionary contains strings with keys and values. The below line returns dictionary only. not array..
    NSDictionary *dictionary = [tableArray objectAtIndex:section];
    return dictionary.allKeys.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *cellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:cellIdentifier];
    }
    NSDictionary *dictionaryOfArray = [tableArray objectAtIndex:indexPath.section];
    NSArray *keysArray = dictionaryOfArray.allKeys;
    cell.textLabel.text = [keysArray objectAtIndex:indexPath.row];
    cell.detailTextLabel.text = [dictionaryOfArray valueForKey:[keysArray objectAtIndex:indexPath.row]];
    return cell;
}