问题
i have an iPhone app in which i have several images. These images add in image view. That image view add sub view with scroll view. Now i want to add a transparent button on every image. How can i do that? I have shown my code below:
- (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(curXLoc, 0);
view.frame = frame;
curXLoc += (kScrollWidth);
}
}
// set the content size so it can be scrollable
[scrollView1 setContentSize:CGSizeMake((kNoImages * 500), 700)];
}
- (void)viewDidLoad{
self.view.backgroundColor = [UIColor viewFlipsideBackgroundColor];
// 1. setup the scrollview for multiple images and add it to the view controller
//
// note: the following can be done in Interface Builder, but we show this in code for clarity
[scrollView1 setBackgroundColor:[UIColor blackColor]];
[scrollView1 setCanCancelContentTouches:NO];
scrollView1.indicatorStyle = UIScrollViewIndicatorStyleWhite;
scrollView1.clipsToBounds = YES; // default is NO, we want to restrict drawing within our scrollview
scrollView1.scrollEnabled = YES;
//imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"image0.jpg"]];
[scrollView1 addSubview:imageView];
[scrollView1 setContentSize:CGSizeMake(500,700)];
scrollView1.minimumZoomScale = 1;
scrollView1.maximumZoomScale = 3;
scrollView1.delegate = self;
[scrollView1 setScrollEnabled:YES];
// pagingEnabled property default is NO, if set the scroller will stop or snap at each photo
// if you want free-flowing scroll, don't set this property.
scrollView1.pagingEnabled = YES;
// load all the images from our bundle and add them to the scroll view
NSUInteger i;
for (i = 1; i <= kNoImages; i++)
{
NSString *imageName = [NSString stringWithFormat:@"page-%d.jpg", i];
UIImage *image = [UIImage imageNamed:imageName];
UIImageView *ImageView = [[UIImageView alloc] initWithImage:image];
// setup each frame to a default height and width, it will be properly placed when we call "updateScrollList"
CGRect rect = ImageView.frame;
rect.size.height = kScrollHeight;
rect.size.width = kScrollWidth;
ImageView.frame = rect;
ImageView.tag = i; // tag our images for later use when we place them in serial fashion
UIButton *btnView2= [UIButton buttonWithType:UIButtonTypeCustom];
[btnView2 setTitle:@"view" forState:UIControlStateNormal];
[btnView2 addTarget:self action:@selector(View:)forControlEvents:UIControlEventTouchDown];
[btnView2 setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
btnView2.frame=CGRectMake(0,0,460,460 );
[scrollView1 addSubview:btnView2];
scrollView1.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;
[scrollView1 addSubview:ImageView];
[ImageView release];
}
[self layoutScrollImages]; // now place the photos in serial layout within the scrollview
}
-(IBAction)View:(id)sender{
NSURL *imgUrl=[[NSURL alloc] initWithString:@"http://farm4.static.flickr.com/3567/3523321514_371d9ac42f.jpg"];
NSData *imgData = [NSData dataWithContentsOfURL:imgUrl];
UIImage *img = [UIImage imageWithData:imgData];
UIImageView *imgView = [[UIImageView alloc] initWithImage:img];
[self.view addSubview:imgView];
//[self.navigationController pushViewController:ivc animated:YES];
[imgUrl release];
}
回答1:
Instead of adding Imageview and transparent button on top of Imageview. You can just add UIButton customtype and set button image to your image in your scrollview. There is no need to take imageview and UIButton both. Just take UIButton and setImage and you will be fine. I tried to give you sample code below from my app. Please modify it as per your need. I think it is what you need.
First of Take all constant in one of global file. I took it in en.lproj. like below.
"TotalThumbnailCount"="6";
"Coloumn"="2";
"ThumbnailHeight"="151";
"ThumbnailWidth"="151";
//Marging between two images
"MarginX" = "6";
"MarginY" = "6";
Then initialize all your local varaibles from global variables. like below
-(void)PopulateVariables{
TotalThumbnail = [NSLocalizedString(@"TotalThumbnailCount",nil) intValue];
Colomn = [NSLocalizedString(@"Coloumn",nil) intValue];
ThumbnailHeight = [NSLocalizedString(@"ThumbnailHeight",nil) intValue];
ThumbnailWidth = [NSLocalizedString(@"ThumbnailWidth",nil) intValue];
MarginX = [NSLocalizedString(@"MarginX",nil) intValue];
MarginY= [NSLocalizedString(@"MarginY",nil) intValue];
}
Now, you should initiate your thumbnail images using UIButton from below function.
-(void)PopulateThumbnails
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
XCordinate=MarginX;
YCordinate = MarginY;file:
for(int i=1; i <=TotalThumbnail;i++){
UIButton *btnMenu = [UIButton buttonWithType:UIButtonTypeCustom];
//NSData *data =UIImageJPEGRepresentation(, 1);
[btnMenu setBackgroundImage:[UIImage imageNamed:[NSString stringWithFormat:@"%d.png",i]] forState:UIControlStateNormal];
CGRect frame = btnMenu.frame;
frame.size.width=ThumbnailWidth;
frame.size.height=ThumbnailHeight;
frame.origin.x=XCordinate;
frame.origin.y=YCordinate;
btnMenu.frame=frame;
btnMenu.tag=i;
btnMenu.alpha = 1;
[btnMenu addTarget:self action:@selector(btnSelected:) forControlEvents:UIControlEventTouchUpInside];
[scrollView addSubview:btnMenu];
XCordinate = btnMenu.frame.origin.x + btnMenu.frame.size.width + MarginX;
if(i%Colomn==0)
{
XPosition = XCordinate;
YCordinate = btnMenu.frame.origin.y + btnMenu.frame.size.height + MarginY;
XCordinate = MarginX;
}
}
[pool release];
}
And then set your scrollview contentsize
scrollView.contentSize = CGSizeMake(XPosition, YCordinate);
When some one tap on any image it will goes in below event.
-(IBAction)btnSelected:(id)sender{
UIButton *btnSelected = sender;
switch (btnSelected.tag) {
}
Let me know if I miss anything and if you don't understand.. Hope this help.
回答2:
You can add UITapGestureRecognizer to each image:
UITapGestureRecognizer *tapGesture = [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapAction:)] autorelease];
[imageView addGestureRecognizer:tapGesture];
[self.view addSubview:imageView];
回答3:
When you create your imageview, create a uibutton and add it as a subview to the imageview. Set the properties of the button to be custom type. Also set the frame of the button same as that of the imageview.
button = [UIButton buttonWithType:UIButtonTypeCustom];
Google how to create a uibutton programatically. You can then add the necessary selectors to handle button press events.
Alternatively you can create a element in Interfacebuilder. A custom class which has a uiimageview and clear uibutton. You can then use this element to add to your uiscrollview.
来源：https://stackoverflow.com/questions/6786170/how-add-a-uibutton-on-every-image-of-image-view-which-is-in-scroll-view