Cocoa-touch – How to access subviews in nested UIScrollViews

cocoa-touchsubviewuiimageviewuiscrollview

I was having trouble getting a UIScrollView with multiple UIImageView subviews to zoom properly so I tried using a UIScrollView with multiple UIScrollView subviews inside of it and a UIImageView inside of each of those. That way one UIScrollView can only scroll and the other can only zoom.

My question is: How can I access subviews of a subview. I know that normally I can access subviews using [scrollView viewWithTag:tagInt]; for example, but I can't seem to access the subviews of a subview using [[scrollView viewWithTag:tagInt] viewWithTag:tagInt2]; since viewWithTag only returns a single UIView and not all of it's subviews.

I could always give each subview a unique tag and access them that way, but that doesn't seem to be the most elegant solution.

What is the best way to access a subView and then get to the subView's subview (ie: access my UIScrollView used for zooming which is a subview of my main view, and then access it's subView UIImageView)?

Best Answer

If you don't feel comfortable subclassing for now, you'd have to assign tags to the UIScrollViews containing images. You'd then have to do what the BobC suggested with a little more work.

for (UIView *subview in [myScrollView subviews])
{
   //check if the current subview is one of the UIScrollViews
   if (subview.tag > 100)
        //do something with the UIScrollView
}

Related Solutions

Ios – How to make a UITextField move up when the keyboard is present – on starting to edit

You will only need a ScrollView if the contents you have now do not fit in the iPhone screen. (If you are adding the ScrollView as the superview of the components just to make the TextField scroll up when keyboard comes up, then it's not needed.)
The standard way to prevent the TextFields from being covered by the keyboard is to move the view up/down whenever the keyboard is shown.

Here is some sample code:

#define kOFFSET_FOR_KEYBOARD 80.0

-(void)keyboardWillShow {
    // Animate the current view out of the way
    if (self.view.frame.origin.y >= 0)
    {
        [self setViewMovedUp:YES];
    }
    else if (self.view.frame.origin.y < 0)
    {
        [self setViewMovedUp:NO];
    }
}

-(void)keyboardWillHide {
    if (self.view.frame.origin.y >= 0)
    {
        [self setViewMovedUp:YES];
    }
    else if (self.view.frame.origin.y < 0)
    {
        [self setViewMovedUp:NO];
    }
}

-(void)textFieldDidBeginEditing:(UITextField *)sender
{
    if ([sender isEqual:mailTf])
    {
        //move the main view, so that the keyboard does not hide it.
        if  (self.view.frame.origin.y >= 0)
        {
            [self setViewMovedUp:YES];
        }
    }
}

//method to move the view up/down whenever the keyboard is shown/dismissed
-(void)setViewMovedUp:(BOOL)movedUp
{
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3]; // if you want to slide up the view

    CGRect rect = self.view.frame;
    if (movedUp)
    {
        // 1. move the view's origin up so that the text field that will be hidden come above the keyboard 
        // 2. increase the size of the view so that the area behind the keyboard is covered up.
        rect.origin.y -= kOFFSET_FOR_KEYBOARD;
        rect.size.height += kOFFSET_FOR_KEYBOARD;
    }
    else
    {
        // revert back to the normal state.
        rect.origin.y += kOFFSET_FOR_KEYBOARD;
        rect.size.height -= kOFFSET_FOR_KEYBOARD;
    }
    self.view.frame = rect;

    [UIView commitAnimations];
}


- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWillShow)
                                             name:UIKeyboardWillShowNotification
                                           object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWillHide)
                                             name:UIKeyboardWillHideNotification
                                           object:nil];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    // unregister for keyboard notifications while not visible.
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                             name:UIKeyboardWillShowNotification
                                           object:nil];

    [[NSNotificationCenter defaultCenter] removeObserver:self
                                             name:UIKeyboardWillHideNotification
                                           object:nil];
}

Svn – How to set max file size for commits in subversion

You just need to add a pre-commit hook on the Subversion repository. See this page for a good start on that.

Best Answer

Related Solutions

Ios – How to make a UITextField move up when the keyboard is present – on starting to edit

Svn – How to set max file size for commits in subversion

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