我通过JSON将一些东西解析成表视图,但我遇到的问题是解析需要大约一秒钟(我知道这是由于网络指示器)但是然后有一个巨大的延迟,直到数据出现在表格视图。
我试着放置[tableView reloadData];在几个地方已经但没有成功。
这是我的代码。
我已将mainThreadQueue和myClassicoAPI定义为宏。
- (void)viewDidLoad
{
[super viewDidLoad];
arrayNeuheiten = [[NSArray alloc] init];
arrayArtikelName = [[NSArray alloc] init];
dictionaryNewStuff = [[NSDictionary alloc] init];
[self parseJSONWithURL:myClassicoAPI];
//[self performSelector:@selector(updateTableView) withObject:nil afterDelay:NO];
[neuheietenTable reloadData];
}
-(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
[neuheietenTable reloadData];
}
-(void) updateTableView {
[neuheietenTable reloadData];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(NSInteger)numberOfRowsInSection:(NSInteger)section {
return 1;
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
//return (self.arrayNeuheiten.count<17)?self.arrayNeuheiten.count : 17;
return MIN(18, arrayNeuheiten.count);
}
-(void) parseJSONWithURL: (NSURL *) jsonURL {
dispatch_async(mainThreadQueue, ^{
NSError *error = nil;
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
NSString *json =[NSString stringWithContentsOfURL:jsonURL encoding:NSJSONWritingPrettyPrinted error:&error];
if (error == nil) {
NSData *jsonData = [json dataUsingEncoding:NSJSONWritingPrettyPrinted];
dictionaryNewStuff = [NSJSONSerialization JSONObjectWithData:jsonData options:kNilOptions error:&error];
if (error == nil) {
dispatch_async(mainThreadQueue, ^{
arrayArtikelName = [[dictionaryNewStuff valueForKey:@"newstuff"] valueForKey:@"Neuheiten"];
arrayNeuheiten = [[dictionaryNewStuff valueForKey:@"newstuff"] valueForKey:@"Neuheiten"];
[neuheietenTable reloadData];
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
});
} else {
nil;
}
} else {
nil;
}
});
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"NeuheitenCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.textLabel.text = [[arrayArtikelName objectAtIndex:indexPath.row] objectForKey:@"name"];
return cell;
}
提前致谢
顿
答案 0 :(得分:2)
您正在主线程上加载同步的数据,这是坏的并阻塞了接口。 尝试使用NSURLConnection加载JSON数据并在
中重新加载UITableView(void)connectionDidFinishLoading:(NSURLConnection *)aConnection
您完成处理后的方法。
答案 1 :(得分:0)
你好我用一个公共网址修改代码并且工作正常。查看有助于解决问题的代码:
- (void)viewDidLoad
{
[super viewDidLoad];
arrayNeuheiten = [[NSArray alloc] init];
arrayArtikelName = [[NSArray alloc] init];
dictionaryNewStuff = [[NSDictionary alloc] init];
[neuheietenTable reloadData];
NSURL *url = [NSURL URLWithString:@"http://122.182.14.104:3004/build/product/15.json"];
[self parseJSONWithURL:url];
//[self performSelector:@selector(updateTableView) withObject:nil afterDelay:NO];
}
-(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(NSInteger)numberOfRowsInSection:(NSInteger)section {
return 1;
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
//return (self.arrayNeuheiten.count<17)?self.arrayNeuheiten.count : 17;
return arrayArtikelName.count;
}
-(void) parseJSONWithURL: (NSURL *) jsonURL {
NSError *error = nil;
NSString *json =[NSString stringWithContentsOfURL:jsonURL encoding:NSJSONWritingPrettyPrinted error:&error];
if (error == nil) {
NSData *jsonData = [json dataUsingEncoding:NSJSONWritingPrettyPrinted];
dictionaryNewStuff = [NSJSONSerialization JSONObjectWithData:jsonData options:kNilOptions error:&error];
if (error == nil) {
arrayArtikelName = [dictionaryNewStuff valueForKey:@"attributes"];
// arrayNeuheiten = [[dictionaryNewStuff valueForKey:@"newstuff"] valueForKey:@"Neuheiten"];
[neuheietenTable reloadData];
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
} else {
nil;
}
}
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"NeuheitenCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.textLabel.text = [[arrayArtikelName objectAtIndex:indexPath.row] objectForKey:@"name"];
return cell;
}