我正在尝试为我的 UITableView 调用 [MyTableviewController.tableview reloaddata] 函数。我认为这样做的最佳位置是 UITableViewController 子类的 -(void) viewWillAppear 方法。

代码在创建类时并没有创建，我尝试实现该方法但收效甚微。

在对 SO 和其他各种网站进行一些研究后，我发现问题可能在于 UIViewController 子类是导航 Controller 的一部分，而导航 Controller 又是选项卡栏 Controller 的一部分。发布的一般建议和代码是对 Controller 中的一个(哪个？)进行子类化并实现 -viewWillAppear 消息。

我的问题是: 1. 有没有办法在不子类化另一个 Controller 的情况下调用这个急需的方法？ 2.如果是这样，我该怎么做？ 3.如果没有，您能否准确地向我解释我必须做什么，更重要的是，为什么我必须这样做？

这是 UITableViewController 的完整代码:

//
//  OverViewController.m
//  NoificationTest
//
//  Created by Mirko Winckel on 15.03.12.
//  Copyright (c) 2012 __MyCompanyName__. All rights reserved.
//

#import "OverViewController.h"
#import "SecondOverViewController.h"
#import "Globals.h"

@interface OverViewController ()

@end

@implementation OverViewController

@synthesize entrys;



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



- (void)viewDidLoad
{
    [super viewDidLoad];

    [self.tableView reloadData];

    if (entrys == nil) 
    {

    NSString* filePath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    NSString* fileName = [[Globals sharedGlobals].selectedProject stringByAppendingString:@".csv"];
    NSString* fileAtPath = [filePath stringByAppendingPathComponent:fileName];
    NSString* content = [[NSString alloc] initWithData:[NSData dataWithContentsOfFile:fileAtPath] encoding:NSUTF8StringEncoding];
    NSString *stringToFind =@"\n";
    entrys = [content componentsSeparatedByString:stringToFind];

    }


    /* 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{

    int weeks = 1+1;

    return weeks;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{

    NSString *sectionHeader = nil;

    if ( section == 0 ) {

       sectionHeader = @"Refresh - test";

    }

    if (  section == 1 ) {
        if ( [Globals sharedGlobals].selectedProject != nil){

            NSString* temp = @"Current in project ";
            [temp stringByAppendingString:[Globals sharedGlobals].selectedProject];

            sectionHeader = temp;

        }

        else {
            sectionHeader = @"No project selected";
        }
    }

    if (  section == 2 ) {
        sectionHeader = @"Week 3";
    }

    if (  section == 3 ) {
        sectionHeader = @"Week 4";
    }

    if (  section == 4 ) {
        sectionHeader = @"Week 5";
    }

    return sectionHeader;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    int rows;

    if (section == 0){
        rows = 1;
    }

    if (section == 1 ){
        rows = [entrys count] -1;
    }



    return rows ;
}

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

    if (cell == nil) {
           cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    NSString *oneLine = [entrys objectAtIndex:indexPath.row];
    NSArray *lineComponents = [oneLine componentsSeparatedByString:@";"];

    cell.textLabel.text = [lineComponents objectAtIndex:0];
    cell.textLabel.textColor = [UIColor colorWithRed:0.0 green:0.8 blue:0.2 alpha:1.0];

    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{



    if (indexPath.section == 0) {

        [self.tableView reloadData];

        [tableView deselectRowAtIndexPath:indexPath animated:YES];



    }






    if (indexPath.section == 1) {

    [tableView deselectRowAtIndexPath:indexPath animated:YES];

    SecondOverViewController *anotherViewController = [[SecondOverViewController alloc] initWithStyle:UITableViewStylePlain];

    NSArray *rowArray = [[entrys objectAtIndex:indexPath.row] componentsSeparatedByString:@";"];

    anotherViewController.oneRow = rowArray;

    [self.navigationController pushViewController:anotherViewController animated:YES];

    } 





    // 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

提前致谢:)

最佳答案

如果您的 ViewController 派生自 UITableViewController，请尝试以这种方式调用 reloadData 函数:

[self.tableView reloadData];

此外，我建议在 viewDidLoad 而不是 viewDidAppear 下调用 reloadData。后者可以意外调用多次(例如，当另一个 View 从堆栈中弹出时)，而前者只调用一次。

例如:

- (void)viewDidLoad {
    [super viewDidLoad];
    [self.tableView reloadData];
}

关于iphone - 在 UITableviewController 中调用 viewWillAppear，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/10652420/