Pass string from UITableView to UIView in iOS

Question

I want to pass 2 string selected from UITableview (CompleteView) to new UIView (DetailView) This is my code:

In CompleteView.h()

@property (nonatomic, retain) NSString *memoString;
@property (nonatomic, retain) NSString *previewString;

In Completeview.m()

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{           
previewString = [PreviewArray objectAtIndex:indexPath.row];
            NSLog(@"Preview string %@",previewString);
            memoString = [MemoArray objectAtIndex:indexPath.row];
            NSLog(@"Memo string %@",memoString);

            DetailView *detailAlert = [[DetailView alloc] initWithFrame:CGRectMake(10, 40, 300, 300)];
            detailAlert.strPreview =previewString ;
            detailAlert.strMemo =  memoString;

            [self.view addSubview:detailAlert];
            [detailAlert show];
            [detailAlert release];
}

In DetailView()

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        originalFrame = frame;

        UIWebView *videoview = [[UIWebView alloc] initWithFrame:CGRectMake(10,80,275.0,150)];
        NSString *url=[NSURL URLWithString:strPreview];
        NSURL *nsurl=[NSURL URLWithString:url];
        NSURLRequest *nsrequest=[NSURLRequest requestWithURL:nsurl];
        [videoview loadRequest:nsrequest];
        [self addSubview:videoview];

    return self;
}

In DetailView.h

@property (nonatomic, retain) NSString* strMemo;
@property (nonatomic, retain) NSString* strPreview;

When run, previewString not send to DetailView. I'm debug, when run strPreview and strMemo in DetailView is 0x00000. Thanks in advance

Answer 1

You can pass custom Initialisers like below . If you wish you can add one parameter to custom Initialisers

In CompleteView.h()

@property (nonatomic, retain) NSString *memoString;
@property (nonatomic, retain) NSString *previewString;

In Completeview.m()

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{           
previewString = [PreviewArray objectAtIndex:indexPath.row];
            NSLog(@"Preview string %@",previewString);
            memoString = [MemoArray objectAtIndex:indexPath.row];
            NSLog(@"Memo string %@",memoString);

            DetailView *detailAlert = [[DetailView alloc] initWithFrame:CGRectMake(10, 40, 300, 300) andPreviewstring:previewString];
            detailAlert.strPreview =previewString ;
            detailAlert.strMemo =  memoString;

            [self.view addSubview:detailAlert];
            [detailAlert show];
            [detailAlert release];
}

In DetailView()

- (id)initWithFrame:(CGRect)frame andPreviewstring:(NSString *)stPreview
{
    self = [super initWithFrame:frame];
    if (self) {
        originalFrame = frame;

        UIWebView *videoview = [[UIWebView alloc] initWithFrame:CGRectMake(10,80,275.0,150)];
        NSString *url=[NSURL URLWithString:strPreview];
        NSURL *nsurl=[NSURL URLWithString:url];
        NSURLRequest *nsrequest=[NSURLRequest requestWithURL:nsurl];
        [videoview loadRequest:nsrequest];
        [self addSubview:videoview];

    return self;
}

In DetailView.h

@property (nonatomic, retain) NSString* strMemo;
@property (nonatomic, retain) NSString* strPreview;
- (id)initWithFrame:(CGRect)frame andPreviewstring:(NSString *)stPreview;

Answer 2

try this:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {           
    previewString = [PreviewArray objectAtIndex:indexPath.row];
    NSLog(@"Preview string %@",previewString);
    memoString = [MemoArray objectAtIndex:indexPath.row];
    NSLog(@"Memo string %@",memoString);

    DetailView *detailAlert = [[DetailView alloc] initWithFrame:CGRectMake(10, 40, 300, 300)];
    detailAlert.strPreview =previewString ;
    detailAlert.strMemo =  memoString;
    [detailAlert createWebView];

    [self.view addSubview:detailAlert];
    [detailAlert show];
    [detailAlert release];

}

write code for string allocation

- (id)initWithFrame:(CGRect)frame {
    self = [super initWithFrame:frame];
    if (self) {
        originalFrame = frame;

        //add following two lines
        strPreview = [[NSString alloc] init];
        strMemo = [[NSString alloc] init];
        //........
        return self;
}

-(void) createWebView {
    UIWebView *videoview = [[UIWebView alloc] initWithFrame:CGRectMake(10,80,275.0,150)];
    NSString *url=[NSURL URLWithString:strPreview];
    NSURL *nsurl=[NSURL URLWithString:url];
    NSURLRequest *nsrequest=[NSURLRequest requestWithURL:nsurl];
    [videoview loadRequest:nsrequest];
    [self addSubview:videoview];
}

Answer 3

The problem here is you are setting two properties in detail view after initializing DetailView. But you are trying to use a property values within the initializer which are yet to be set.

As I can see there are two options you can try out.

1. Write another initializer which accept these two properties. So that you can use those two properties in that initializer.

   • (id)initWithFrame:(CGRect)frame strMemo:(NSString *)memo strPreview:(NSString *)preview { self = [super initWithFrame:frame]; if (self) { originalFrame = frame;

     UIWebView *videoview = [[UIWebView alloc] initWithFrame:CGRectMake(10,80,275.0,150)];
     NSString *url=[NSURL URLWithString:preview];
     NSURL *nsurl=[NSURL URLWithString:url];
     NSURLRequest *nsrequest=[NSURLRequest requestWithURL:nsurl];
     [videoview loadRequest:nsrequest];
     [self addSubview:videoview];
     
     return self;
     

     }

2. Or else you can extract the logic in the current initializer and put them in to a separate method which you can called after setting two properties from the CompleteView.