Scrolling top to bottom using UIScrollView - iphone

Question

I am looking for an example that show just vertical scrolling in iPhone.
The Apple supplied Scrolling example allows swiping of images left to
right.
Example Link
Example Link
I want to have my images scroll top to bottom like Instagram
App.
I research about it and found lots of example, but they all show
horizontal scrolling.
Example
Example
Example
Does anyone know how to do this?
I appreciate if you send me a link to a tutorial.

Answer 1

Hi i solved your problem with apple code,
just change the function with
- (void)layoutScrollImages
{
UIImageView *view = nil;
NSArray *subviews = [scrollView1 subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 0;
for (view in subviews)
{
if ([view isKindOfClass:[UIImageView class]] && view.tag > 0)
{
CGRect frame = view.frame;
frame.origin = CGPointMake(0,curXLoc);
view.frame = frame;
curXLoc += (kScrollObjHeight);
}
}
// set the content size so it can be scrollable
[scrollView1 setContentSize:CGSizeMake(([scrollView1 bounds].size.width),kNumImages * kScrollObjHeight)];
}
or if you want sample then i will give you

Answer 2

For your purpose refer your link:
http://idevzilla.com/2010/09/16/uiscrollview-a-really-simple-tutorial/
There is a code like:
scroll.contentSize = CGSizeMake(self.view.frame.size.width * numberOfViews, self.view.frame.size.height);
For horizontal scrolling you need to set the width of contentSize property to a higher value than the scroll view's frame width. Likewise for vertical scrolling you need to set the height of contentSize property to a higher value than the scroll view's frame height.
Reference
In the above code it can be done like:
scroll.contentSize = CGSizeMake(self.view.frame.size.width, numberOfViews * self.view.frame.size.height);

Answer 3

You can use the following code to scroll images from top to bottom and vice versa.!!
- (void)viewDidLoad
{
//....
UISwipeGestureRecognizer *recognizer;
//for scrolling up
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(SwipeUp)]; // calling method SwipeUp
[recognizer setDirection:(UISwipeGestureRecognizerDirectionUp)];
[[self view] addGestureRecognizer:recognizer];
//for scrolling down
UISwipeGestureRecognizer *recognizer1;
recognizer1 = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(SwipeDown)]; //calling method SwipeDown
[recognizer1 setDirection:(UISwipeGestureRecognizerDirectionDown)];
[[self view] addGestureRecognizer:recognizer1];
}
//Initialise and synthesise IBOutlet UIImageView *bgImage;
-(IBAction)SwipeUp
{
[bgImage setImage:[UIImage imageNamed:#"yourImage1"] ];
bgImage.opaque=YES;
[self.view addSubview:bgImage];
}
-(IBAction)SwipeDown
{
[bgImage setImage:[UIImage imageNamed:#"yourImage2"] ];
bgImage.opaque=YES;
[self.view addSubview:bgImage];
}

Answer 4

I don't know if I understood correctly what you want to accomplish but basically you can set the position of you scrollView using setContentOffset.
CGPoint bottomOffset = CGPointMake(0, scrollView.contentSize.height - self.scrollView.bounds.size.height);
[scrollView setContentOffset:bottomOffset animated:YES];

Answer 5

There are several ways of doing this for example:
Using the UITableView with Custom cell
Adding UIScrollingView & adding the content/images & increasing the
height of scrollview according to number of objects in array.
Here is the code snippet which creates a 2*2 Grid for images :
//Over here adding the image names into the Array
NSMutableArray *imageArray=[[NSMutableArray alloc]init];
[Arr addObject:[UIImage imageNamed:#"image_1.png"]];
[Arr addObject:[UIImage imageNamed:#"image_2.png"]];
[Arr addObject:[UIImage imageNamed:#"image_3.png"]];
[Arr addObject:[UIImage imageNamed:#"image_4.png"]];
[Arr addObject:[UIImage imageNamed:#"image_5.png"]];
// Initlaizing the ScrollView & setting the frame :
scrollView = [[UIScrollView alloc]initWithFrame:CGRectMake(0, 0,320, 460)];
[scrollView setBackgroundColor:[UIColor clearColor]];
scrollView.showsHorizontalScrollIndicator = NO;
scrollView.showsVerticalScrollIndicator = NO;
int row = 0;
int column = 0;
for(int i = 0; i < imageArray.count; i++) {
UIButton * button = [UIButton buttonWithType:UIButtonTypeCustom];
button.backgroundColor=[UIColor clearColor];
button.frame = CGRectMake(column*160+0,row*210+10, 160, 190);
[button setImage:[imageArray objectAtIndex:i] forState:UIControlStateNormal];
[button setBackgroundColor:[UIColor clearColor]];
[button addTarget:self action:#selector(chooseCustomImageTapped:) forControlEvents:UIControlEventTouchUpInside];
button.tag = i;
[view1 addSubview:button];
if (column == 1) {
column = 0;
row++;
} else {
column++;
}
}
[scrollView setContentSize:CGSizeMake(320, (row+1) * 210)];
[self.view addSubview:view1];
//Here is the method used for Tapping :
- (IBAction)chooseCustomImageTapped:(id)sender
{
}
Now,once the scrollView is ready for Vertical scrolling, you can do your own customization accordingly. I hope this would work for you.