有时无法以编程方式创建的UIButton触发按钮单击事件

Question

I have added UIScrollView from the storyboard and inside that scroll view I have another UIView as a container view. Behind the UIScrollView I have a UIImageView too as a sibling. This is my View hierarchy.

Now I am adding Views into this container view programmatically.

-(void)setUI
   {
      int i;
      for ( i=0; i<[array count]; i++) {

      NSLog(@"Object at index %i  %@",i,[array objectAtIndex:i]);

      UIView *view=[self GetAlertView:i];

    [self.contentView addSubview:view];
    float sizeOfContent = 0;

    if (notY+viewParent.frame.size.height>self.contentView.frame.size.height) {
        CGRect frame=self.contentView.frame;
        frame.size.height=notY;
        self.contentView.frame=frame;
    }



    self.mainScroll.contentSize = self.contentView.frame.size;


}

This is how I generate views.

-(UIView *)GetAlertView :(int)index
     {
       viewParent=[[UIView alloc] initWithFrame:CGRectMake(10, notY,     self.view.frame.size.width-20, 100)];
[viewParent setBackgroundColor:[UIColor clearColor]];
[viewParent setUserInteractionEnabled:YES];


UIImageView *backImage=[[UIImageView alloc] initWithFrame:CGRectMake(0, 0, viewParent.frame.size.width, viewParent.frame.size.height)];
[backImage setImage:[UIImage imageNamed:@"AlertBack"]];


//-------TITLE LABEL--------------

UILabel *lblTitle=[[UILabel alloc] initWithFrame:CGRectMake(20, 20, viewParent.frame.size.width-60, 30)];

[lblTitle setText:[[[array objectAtIndex:index] objectForKey:@"Info"] valueForKey:@"Headline"]];
[lblTitle setFont:[UIFont fontWithName:@"HelveticaNeue-Bold" size:15]];
[lblTitle setTextAlignment:NSTextAlignmentLeft];
[lblTitle setTextColor:[UIColor whiteColor]];

//-------ICON IMAGE------------

UIImageView *imgIco=[[UIImageView alloc] initWithFrame:CGRectMake(lblTitle.frame.origin.x+lblTitle.frame.size.width, 20, 30, 30)];

NSString *imgUrl=[[[[array objectAtIndex:index] objectForKey:@"Info"] objectForKey:@"Resource"] valueForKey:@"Uri"];
if([[array objectAtIndex:index] valueForKey:@"Realimg"]!=nil)
{
    [imgIco setImage:[[array objectAtIndex:index] valueForKey:@"Realimg"]];
}
else
{
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        NSURL *imageURL = [NSURL URLWithString:imgUrl];
        NSData *imageData = [NSData dataWithContentsOfURL:imageURL];
        UIImage *image = [UIImage imageWithData:imageData];
        dispatch_async(dispatch_get_main_queue(), ^{
            if(image!=nil){
                @try {
                    NSMutableDictionary *objectDict=[[NSMutableDictionary alloc] initWithDictionary:[[array objectAtIndex:index] mutableCopy]];
                    [objectDict setObject:image forKey:@"Realimg"];
                    [array replaceObjectAtIndex:index withObject:objectDict];

                }
                @catch (NSException *exception) {

                }
                @finally {

                }

            }

            [imgIco setImage:image];

        });
    });

}


UILabel *lblMessage=[[UILabel alloc] initWithFrame:CGRectMake(20, lblTitle.frame.origin.y+lblTitle.frame.size.height+10, viewParent.frame.size.width-40, 10)];
[lblMessage setUserInteractionEnabled:NO];

[lblMessage setNumberOfLines:0];
CGSize maximumLabelSize = CGSizeMake(viewParent.frame.size.width-40, FLT_MAX);
NSString *strDescript=[[[array objectAtIndex:index] objectForKey:@"Info"]valueForKey:@"Description"];


[lblMessage setText:strDescript];
[lblMessage setFont:[UIFont fontWithName:@"HelveticaNeue" size:14]];

CGSize expectedLabelSize = [strDescript sizeWithFont:lblMessage.font constrainedToSize:maximumLabelSize lineBreakMode:lblMessage.lineBreakMode];
//adjust the label the the new height.
CGRect newFrame = lblMessage.frame;
newFrame.size.height = expectedLabelSize.height;
lblMessage.frame = newFrame;
if (lblMessage.frame.size.height>10) {
    float extendedH=lblMessage.frame.size.height-10;


    CGRect newFrameMsg = viewParent.frame;
    newFrameMsg.size.height = viewParent.frame.size.height+extendedH;
    viewParent.frame = newFrameMsg;

    CGRect newImgFrame=backImage.frame;
    newImgFrame.size.height=backImage.frame.size.height+extendedH;
    backImage.frame=newImgFrame;

}

[lblMessage setTextColor:[UIColor whiteColor]];

NSLog(@"Circle %lu",[[[[[array objectAtIndex:index] objectForKey:@"Info"] objectForKey:@"Area"] objectForKey:@"Circle"] count]);
int circleCount=[[[[[array objectAtIndex:index] objectForKey:@"Info"] objectForKey:@"Area"] objectForKey:@"Circle"] count];

NSLog(@"Geocode %@",[[[[array objectAtIndex:index] objectForKey:@"Info"] objectForKey:@"Area"] objectForKey:@"Geocode"]);
NSString *strGeoCod=[[[[array objectAtIndex:index] objectForKey:@"Info"] objectForKey:@"Area"] objectForKey:@"Geocode"];

NSLog(@"Polygon %lu",[[[[[array objectAtIndex:index] objectForKey:@"Info"] objectForKey:@"Area"] objectForKey:@"Polygon"] count]);
int polygonCount=[[[[[array objectAtIndex:index] objectForKey:@"Info"] objectForKey:@"Area"] objectForKey:@"Polygon"] count];

UIImageView *imgEvac;
UIButton *btnEvac;


if (circleCount!=0 || [strGeoCod length]!=0 || polygonCount!=0) {
    //----------EVACUATE IMAGE---------------
    imgEvac=[[UIImageView alloc] initWithFrame:CGRectMake(20, lblMessage.frame.origin.y+lblMessage.frame.size.height+5, 20, 30)];
    [imgEvac setUserInteractionEnabled:NO];
    imgEvac.animationImages=[NSArray arrayWithObjects:[UIImage imageNamed:@"Evac1"],
                             [UIImage imageNamed:@"Evac2"],
                             [UIImage imageNamed:@"Evac3"],
                             [UIImage imageNamed:@"Evac4"],
                             [UIImage imageNamed:@"Evac5"],
                             [UIImage imageNamed:@"Evac6"],
                             [UIImage imageNamed:@"Evac7"],
                             [UIImage imageNamed:@"Evac8"],
                             [UIImage imageNamed:@"Evac9"],
                             [UIImage imageNamed:@"Evac10"],
                             [UIImage imageNamed:@"Evac11"],
                             [UIImage imageNamed:@"Evac12"],
                             [UIImage imageNamed:@"Evac13"],
                             [UIImage imageNamed:@"Evac14"],nil];
    imgEvac.animationDuration = 1.0f;
    imgEvac.animationRepeatCount = 0;
    [imgEvac startAnimating];



    //----------EVACUATE BUTTON-------------
    btnEvac=[UIButton buttonWithType:UIButtonTypeCustom] ;
    [btnEvac setTitle:@"Evacuate" forState:UIControlStateNormal];
    [btnEvac setTitleColor:[UIColor greenColor] forState:UIControlStateNormal];
    [btnEvac addTarget:self action:@selector(EvacuateClick:) forControlEvents:UIControlEventTouchUpInside];

    btnEvac.frame=CGRectMake(imgEvac.frame.origin.x+imgEvac.frame.size.width+5, lblMessage.frame.origin.y+lblMessage.frame.size.height+5, 75, 30);






    intlbldateX=btnEvac.frame.origin.x+btnEvac.frame.size.width;

}

else
{
    intlbldateX=20;
}





//----------DATE LABEL------------------
UILabel *lblDate=[[UILabel alloc] initWithFrame:CGRectMake(intlbldateX, lblMessage.frame.origin.y+lblMessage.frame.size.height+5, viewParent.frame.size.width-(intlbldateX+10), 30)];
[lblDate setUserInteractionEnabled:NO];
[lblDate setBackgroundColor:[UIColor redColor]];
[lblDate setText:[[array objectAtIndex:index]valueForKey:@"Sent"]];
[lblDate setFont:[UIFont fontWithName:@"HelveticaNeue-Bold" size:15]];
[lblDate setTextAlignment:NSTextAlignmentRight];
[lblDate setTextColor:[UIColor whiteColor]];

CGRect newFrame2=viewParent.frame;
newFrame2.size.height=viewParent.frame.size.height+10;
viewParent.frame=newFrame2;

CGRect newImgFrame2=backImage.frame;
newImgFrame2.size.height=backImage.frame.size.height+10;
backImage.frame=newImgFrame2;

//--------- VERTICLE LINE--------------

UIView *vwVerticle=[[UIView alloc] initWithFrame:CGRectMake(0, 0, 10, viewParent.frame.size.height)];
[vwVerticle setUserInteractionEnabled:NO];
[vwVerticle setBackgroundColor:[self colorWithHexString:[[[[[array objectAtIndex:index]objectForKey:@"Info"] objectForKey:@"Resource"] valueForKey:@"ColorCode"] stringByReplacingOccurrencesOfString:@"#" withString:@""]]];

[viewParent addSubview:backImage];
[viewParent addSubview:lblTitle];
[viewParent addSubview:imgIco];
[viewParent addSubview:lblMessage];
[viewParent addSubview:imgEvac];

[viewParent addSubview:lblDate];
[viewParent addSubview:vwVerticle];
[viewParent addSubview:btnEvac];


notY=viewParent.frame.origin.y+viewParent.frame.size.height+20;


return viewParent;

}

But my problem is this btnEvac is not clickable. But sometimes I can click it only one time. This is my button click event.

-(IBAction)EvacuateClick :(UIButton *)sender
  {
     NSLog(@"Evacuate clicked");
  }

Sometimes this is firing in the very first time. After that nothing happens. I dont know whats the reason.I have set the User interaction enabled=YES to my scroll view and container view too. but not to the splash image view. I hope I dont wanna set that too. Please help me.

Thanks

This is how I load more view to the bottom

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
float bottomEdge = self.mainScroll.contentOffset.y + self.mainScroll.frame.size.height;
if (bottomEdge >= self.mainScroll.contentSize.height) {
    // we are at the end

    //[self performSelectorInBackground:@selector(callscrol) withObject:nil];
    [self callscrol];
}

}

-(void)callscrol

{

if(!loading&& !resNull)
{
    float offs = (self.mainScroll.contentOffset.y+self.mainScroll.bounds.size.height);
    float val = (self.mainScroll.contentSize.height);
    if (offs==val)
    {
        loading=YES;
        start_rec+=1;

        [self performSelectorInBackground:@selector(LoadData) withObject:nil];

    }
}

}

And get more data from the server

-(void)LoadData

{

[self.actind startAnimating];
[self.actind setHidden:NO];
loading=YES;

NSString *serverURL =  [[[NSBundle mainBundle] infoDictionary] objectForKey:@"BaseURL"];
NSString *queryString=[NSString stringWithFormat:@"GetDisasterAlertsJson?authCode=%@&lastUpdated=%@&version=%@&langId=%@&pageNo=%@&noOfMessages=%@",dm.strAuthCode,lastUpdate,@"1.0",@"1",[NSString stringWithFormat:@"%i",start_rec],@"5"];
NSString *urlString=[NSString stringWithFormat:@"%@%@",serverURL,queryString];
// Create the request.
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:urlString]];
// Create url connection and fire request
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
    if (!data) {
        NSLog(@"%s: sendAynchronousRequest error: %@", __FUNCTION__, connectionError);
        return;
    } else if ([response isKindOfClass:[NSHTTPURLResponse class]]) {
        NSInteger statusCode = [(NSHTTPURLResponse *)response statusCode];
        if (statusCode != 200) {
            NSLog(@"%s: sendAsynchronousRequest status code != 200: response = %@", __FUNCTION__, response);
            return;
        }
    }

    NSError *parseError = nil;
    NSData *dataXMLRemoved=[self ReplaceXMLData:data];
    NSLog(@"======= Data XML Removed ======== %@",dataXMLRemoved);
    dictionary = [NSJSONSerialization JSONObjectWithData:dataXMLRemoved options:NSJSONReadingAllowFragments error:&parseError];

    if (!dictionary) {
        NSLog(@"%s: JSONObjectWithData error: %@; data = %@", __FUNCTION__, parseError, [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);
        resNull=NO;
        return;
    }


    // now you can use your `dictionary` object

    else
    {
        NSLog(@"JSON Dictionary================ %@",dictionary);
        array=[dictionary objectForKey:@"Cmessage"];
        NSLog(@"Array ####### %@",array);
        resNull=NO;
        loading=NO;
        [self.actind stopAnimating];
        [self.actind setHidden:YES];
        [self setUI];


    }
}];

}

Answer 1

I'm not sure if this is your problem but by default UIScrollViews delay touches from filtering through to embedded views for scrolling performance. This can make it seem like buttons aren't being triggered every time when really it just takes about a second for the touch event to fire on the embedded view.

Try turning this setting off on your scrollview.

self.mainScroll.delaysContentTouches = NO;