how to remove subviews from scrollview?

how do i remove all subviews from my scrollview...

i have a uiview and a button above it in the scrollview something like this....

here is my code to add subview in scroll view

-(void)AddOneButton:(NSInteger)myButtonTag {
lastButtonNumber = lastButtonNumber + 1;

if ((lastButtonNumber == 1) || ((lastButtonNumber%2) == 1)) {
btnLeft = 8;}
else if ((lastButtonNumber == 2) || ((lastButtonNumber%2) == 0)) {
btnLeft = 162;
}
CGRect frame1 = CGRectMake(btnLeft, btnTop, 150, 150);
CGRect frame2 = CGRectMake(btnLeft, btnTop, 150, 150);
UIButton *Button = [UIButton buttonWithType:UIButtonTypeCustom];
Button.frame = frame1;
Button.tag = myButtonTag;
[Button addTarget:self action:@selector(buttonClick:) forControlEvents:UIControlEventTouchUpInside];
[Button setBackgroundColor:[UIColor clearColor]];
[Button setBackgroundImage:[UIImage imageNamed:@"WaitScreen.png"] forState:UIControlStateHighlighted];

    GraphThumbViewControllerobj = [[GraphThumbViewController alloc] initWithPageNumber:[[GraphIdArray objectAtIndex:myButtonTag]intValue]];
    GraphThumbViewControllerobj.view.frame=frame2;
    GraphThumbViewControllerobj.lblCounter.text=[NSString stringWithFormat:@"%d of %d",myButtonTag+1,flashCardsId.count];
    GraphThumbViewControllerobj.lblQuestion.text=[flashCardText objectAtIndex:myButtonTag];
    [myScrollView addSubview:GraphThumbViewControllerobj.view];


[myScrollView addSubview:Button];


if ((lastButtonNumber == 2) || ((lastButtonNumber%2) == 0)) {
btnTop = btnTop + 162;
}
if (btnTop+150 > myScrollView.frame.size.height) {
myScrollView.contentSize = CGSizeMake((myScrollView.frame.size.width), (btnTop+160));}
}

and here is the code to remove subviews

if(myScrollView!=nil)
{
        while ([myScrollView.subviews count] > 0) {
            //NSLog(@"subviews Count=%d",[[myScrollView subviews]count]);
            [[[myScrollView subviews] objectAtIndex:0] removeFromSuperview];
}

alt text http://www.freeimagehosting.net/uploads/e5339a1f51.png

---

To remove all the subviews from any view, you can iterate over the subviews and send each a removeFromSuperview call:

// With some valid UIView *view:
for(UIView *subview in [view subviews]) {
    [subview removeFromSuperview];
}

This is entirely unconditional, though, and will get rid of all subviews in the given view. If you want something more fine-grained, you could take any of several different approaches:

Maintain your own arrays of views of different types so you can send them removeFromSuperview messages later in the same manner

Retain all your views where you create them and hold on to pointers to those views, so you can send them removeFromSuperview individually as necessary

Add an if statement to the above loop, checking for class equality. For example, to only remove all the UIButtons (or custom subclasses of UIButton) that exist in a view, you could use something like:

// Again, valid UIView *view:
for(UIView *subview in [view subviews]) {
    if([subview isKindOfClass:[UIButton class]]) {
        [subview removeFromSuperview];
    } else {
        // Do nothing - not a UIButton or subclass instance
    }
}

---

An old question; but as it's the first hit on Google for this I thought I'd also make a note that there's also this method:

[[myScrollView subviews] makeObjectsPerformSelector:@selector(removeFromSuperview)];

You can't do the isKindOfClass check with this, but it's still a good solution to know about.

Edit: Another point to note is that the scrollbar of a scrollview is added as a subview to that scrollview. Thus if you iterate through all the subviews of a scrollview you will come across it. If removed it'll add itself again - but it's important to know this if you're only expecting your own UIView subclasses to be in there.

Amendment for Swift 3:

myScrollView.subviews.forEach { $0.removeFromSuperview() }

---

To add to what Tim said, I noticed that you are tagging your views. If you wanted to remove a view with a certain tag you could use:

[[myScrollView viewWithTag:myButtonTag] removeFromSuperview];

链接地址: http://www.djcxy.com/p/74374.html

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