I'm using the following code to detect a touch on a table cell image. How would I go about enlarging the image on that touch?
The part I'm stuck on is how would I make the cell.userSubmittedImageView accessible from the myFunction method?
from cellForRowAtIndexPath: method
...
cell.userSubmittedImageView.userInteractionEnabled = YES;
cell.userSubmittedImageView.tag = indexPath.row;
UITapGestureRecognizer *tapped = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(myFunction:)];
tapped.numberOfTapsRequired = 1;
[cell.userSubmittedImageView addGestureRecognizer:tapped];
return cell;
}
-(void)myFunction :(id) sender
{
UITapGestureRecognizer *gesture = (UITapGestureRecognizer *) sender;
NSLog(#"Tag = %d", gesture.view.tag);
}
Assuming that your userSubmittedImageView is an UIImageView you can do
UIImageView * userSubmittedImageView = (UIImageView *)gesture.view;
Related
I am dynamically creating UILabels and then saving their tag in an NSMutableArray. I then have a method that detects taps (clicks) on these UILabels. Basically when a UILabel that has been dynamically generated is clicked I want to have it deleted without deleting other labels. However, in future I may want to do more then just delete. But at the moment I feel like I am stuck at a dead end trying to find a way to do this. Any ideas?
Heres my code:
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
// set corner radius
coverview.hidden=YES;
labeltextfield.hidden=YES;
textcreate.hidden=YES;
labeltags = [NSMutableArray array];
labeltext = [NSMutableArray array];
}
-(IBAction)removeboard
{
[labeltextfield resignFirstResponder];
}
-(void)showtextcreator {
// Create bg cover
coverview.hidden=NO;
labeltextfield.hidden=NO;
textcreate.hidden=NO;
//Make sure creating screen is always on top
[self.view bringSubviewToFront:coverview];
[self.view bringSubviewToFront:labeltextfield];
[self.view bringSubviewToFront:textcreate];
}
-(void)createtext {
NSInteger obj = [labeltags count] +1 ;
[labeltags addObject:[NSNumber numberWithInteger:0]];
int posx = arc4random() % 300 ;
int posy = arc4random() % 400 ;
int frame = arc4random() % 400 ;
NSString *txt = labeltextfield.text;
// NSString *framename = (#"frame%i",frame);
[labeltext addObject:txt];
[labeltags addObject:[NSNumber numberWithInteger:0]];
CGRect labelframe = CGRectMake( posx, posy, 100, 30);
label = [[UILabel alloc] initWithFrame: labelframe];
[label setText: [NSString stringWithFormat:#"%#", txt]];
[label setTextColor: [UIColor orangeColor]];
label.backgroundColor = [UIColor clearColor];
label.tag=obj;
[self.view addSubview: label];
label.userInteractionEnabled = YES;
UIPanGestureRecognizer *gesture = [[UIPanGestureRecognizer alloc]
initWithTarget:self
action:#selector(labelDragged:)];
[label addGestureRecognizer:gesture];
UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapAction)];
[label addGestureRecognizer:recognizer];
coverview.hidden=YES;
labeltextfield.hidden=YES;
textcreate.hidden=YES;
}
- (void)labelDragged:(UIPanGestureRecognizer *)gesture
{
label = (UILabel *)gesture.view;
CGPoint translation = [gesture translationInView:label];
// move label
label.center = CGPointMake(label.center.x + translation.x,
label.center.y + translation.y);
// reset translation
[gesture setTranslation:CGPointZero inView:label];
}
- (void)tapAction {
UILabel *labelnew = (UILabel *)[self.view viewWithTag:1];
NSLog(#"Text is %#",labelnew.text);
}
UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapAction:)];
[label addGestureRecognizer:recognizer];
- (void)tapAction:(UITapGestureRecognizer *)tapGesture {
UILabel *labelTapped = (UILabel *)tapGesture.view;
//delete it using removeFromSuperView or do whatever you need with tapped label
}
Details:
1.Modify your -(void)createtext method.
2: Add a parameter to the target for UITapGestureRecognizer
3.Receive the sender gesture in - (void)tapAction:
4.Get the tapped UILabel.
Thats it.
I created simple UIScrollView that have images. Each time an image pressed i want to change that image, how can I do it?
I creating this UIScrollView and initializing it with NSMutableArray with images.
UIScrollView *myScroll = [[UIScrollView alloc] initWithFrame: CGRectMake (0,100,200,30)];
NSMutableArray = *images = [NSMutableArray alloc] initWithObjects: img1,img2,img3,nil];
for (int i=0; i<3; i++)
{
UIImageView *imageV = [UIImageView alloc];
[imageV setImage:[images objectAtIndex:i]];
[myScroll addSubview:imageV];
[imageV release];
}
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget: self action:#selector (changeImg:)];
[myScroll addGestureRecognizer: singleTap];
and the toucing I'm cathing with the touched place on the scroll:
- (void) singleTapGestureCaptured:(UITapGesturerecongnizer *) gesture
{
CGPoint touch = [gesture locationInView:myScroll];
}
By X,Y of touched item i know what image was selected
Here I need to change for example the first image of myScroll...How can i do it?
Add UITapGestureRecognizer on UIImageView and set its userInractionEnabled: YES which is NO by default for UIImageView.
UIScrollView *myScroll = [[UIScrollView alloc] initWithFrame: CGRectMake (0,100,200,30)];
NSMutableArray = *images = [NSMutableArray alloc] initWithObjects: img1,img2,img3,nil];
for (int i=0; i<3; i++)
{
//In your question you didn't set `imageView` frame so correct it
UIImageView *imageV = [[UIImageView alloc]initWithFrame:yourFrame];
[imageV setImage:[images objectAtIndex:i]];
[imageV setUserInteractionEnabled:YES];
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget: self action:#selector (changeImg:)];
[imageV addGestureRecognizer: singleTap];
[myScroll addSubview:imageV];
[imageV release];
}
After adding all imageView successfully you get them click like this :-
-(void)changeImg:(id)sender
{
UIGestureRecognizer *recognizer = (UIGestureRecognizer*)sender;
UIImageView *imageView = (UIImageView *)recognizer.view;
[imageView setImage:[UIImage imageNamed:#"anyImage.png"]];
}
Your application will crash because you are accessing the index 3, but there is not any object at index 3.
UIScrollView *myScroll = [[UIScrollView alloc] initWithFrame: CGRectMake (0,100,200,30)];
NSMutableArray = *images = [NSMutableArray alloc] initWithObjects: img1,img2,img3,nil];
[myScroll addSubview:[images objectAtIndex:0];
[myScroll addSubview:[images objectAtIndex:1];
[myScroll addSubview:[images objectAtIndex:2];
Now you can access the image view with tagValue
-(void)changeImg :(UIGestureRecognizer*)recog
{
UIScrollView *scroll = (UIScrollView*)recog.view;
CGPoint point = scroll.contentOffset;
int imagetag = (point.y/scroll.frame.size.height);
UIImageView *image=(UIImageView*)[[scroll subviews] objectAtIndex:imagetag];
NSLog(#"Image tag = %d",image.tag);
image.image=[UIImage imageNamed:#"Icon-72.png"];
}
A simple implementation will be, if you use a custom button and change its image on its IBAction.. Still you can addGesture to ur UIImageView too and on the
if(recognizer.state == UIGestureRecognizerStateBegan)
you can change the image on runtime.
I hope this helps. Cheers!!
I have created a UITableView with a custom UITableViewCell. My cell includes one UIImageView on the left and UITextView on the right.
Inside UITableViewController, I set both image and text in tableview cellForRowAtIndexPath.
Everything shows fine but now I need to implement didSelectRowAtIndex and I need to distinguish if UIImageView or UITextView of the cell has been clicked.
Let's say, image clicking is representing delete action and the rest of the cell editing action.
Rather than adding the gesture recognisers to each individual cell, you can add one to the table view and determine which cell was selected from the point of the users touch, and then determine if the user touched the image or the cell.
First make sure your controller adopts the UIGestureRecognizerDelegate protocol.
#interface MyTableViewController() <UIGestureRecognizerDelegate>
#end
Then add the UIGestureRecognizer to the UITableView when the view loads.
- (void)viewDidLoad
{
[super viewDidLoad];
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
singleTap.delegate = self;
singleTap.numberOfTapsRequired = 1;
singleTap.numberOfTouchesRequired = 1;
[self.tableView addGestureRecognizer:singleTap];
}
This delegate method determines if the handleTap: method should be executed. If it can find an indexPath from the users touch, then it returns YES otherwise it returns NO.
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
UITableView *tableView = (UITableView *)gestureRecognizer.view;
CGPoint p = [gestureRecognizer locationInView:gestureRecognizer.view];
if ([tableView indexPathForRowAtPoint:p]) {
return YES;
}
return NO;
}
Once we have determined if the user has clicked in a cell, the handleTap: method is called, which then decides if the user touched the image, or any other part of the cell.
- (void)handleTap:(UITapGestureRecognizer *)tap
{
if (UIGestureRecognizerStateEnded == tap.state) {
UITableView *tableView = (UITableView *)tap.view;
CGPoint p = [tap locationInView:tap.view];
NSIndexPath* indexPath = [tableView indexPathForRowAtPoint:p];
[tableView deselectRowAtIndexPath:indexPath animated:NO];
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
CGPoint pointInCell = [tap locationInView:cell];
if (CGRectContainsPoint(cell.imageView.frame, pointInCell)) {
// user tapped image
} else {
// user tapped cell
}
}
}
You could subclass UITableViewCell and override touchesEnded.
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded:touches withEvent:event];
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView:self];
UIView *hitView = [self hitTest:location withEvent:event];
if (hitView == myImageView) ...;
if (hitView == myTextView) ...;
}
You need to keep some reference to your UIImageView and UITextView (they should probably be properties of your cell).
You can of course override touchesBegan instead of touchesEnded, depends on what functionality you want to achieve.
a very abstract and general answer is to do the following
For each UIImage and UILabel you add set their tag to be the indexPath.row
//When creating the label and image add a recognizer to them
label.tag = indexPath.row;
imageView.tag = indexPath.row;
Then add a UITapGestureRecognizer on each image and label, like so
UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(handleTap:)];
[label addGestureRecognizer:recognizer];
[imageView addGestureRecognizer:recognizer];
}
- (void) handleTap:(UITapGestureRecognizer*)recognizer
{
UIView *view = recognizer.view;
int row = view.tag;
if ([view isKindOfClass:[UILabel class]]) {
//Row is row
//and the label is pressed
}
if ([view isKindOfClass:[UIImageView class]]) {
//Row is row
//and the imageview is pressed
}
}
Make the image a UIButton. When the button's action is triggered, you know the user tapped the image (cell will NOT be selected). If cell is selected, you know the user tapped somewhere else on the row (including text view or label).
Also, set the button's tag property to, e.g. the cell's row index so you can know which row's image was tapped.
you have two option is to implement :-
1--add UITapGestureRecognizer in your "uitableviewcell" and make it point to image view
and pass "indexpath" as parameter to selector and make the delegate pass it to tableviewcell
UILabel *label = =[UILabel alloc]init];
label.userInteractionEnabled = YES;
UITapGestureRecognizer *tapGesture =
[[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(labelTap)] autorelease];
[label addGestureRecognizer:tapGesture];
-(void)labelTap{
[delegate performselector#selector(labeltapped:)withobject:indexpath];
}
2- Second way is to check the sender of DidSelectRowAtIndexPath of type [imageview or label];
but i prefer the first way
I got this solution on this site: Click an UIImage and open an UIImageView in Objective-c
Add UITapGestureRecognizer to your UIImageView:
UITapGestureRecognizer *tapRecognizer;
tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(yourSelector)];
[thumbnail addGestureRecognizer:tapRecognizer];
[tapRecognizer release];
thumbnail.userInteractionEnabled = YES; // very important for UIImageView
This is working very fine for single ImageView, but I am adding more than one (about to 20) to my scrollView then How can I differentiate which ImageView will tapped or selected by user. I tried to set my own #selector(imageClicked), but it only returns tag for last imageView.
I am adding addGestureRecognizer in a loop, as I load 20 static images dynamically in an imageView.
This might help
for(int i=0;i<20;i++)
{
UIImageView *img=[[UIImageView alloc]initWithImage:[UIImage imageNamed:#"yourimage.png"]];
[img setTag:i];
img.frame= //set frame accordingly;
img.userInteractionEnabled = YES;
UITapGestureRecognizer *tap =
[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
[img addGestureRecognizer:tap];
[tap release];
[scrollView addSubView:img];
}
- (void)handleTap:(UITapGestureRecognizer *)recognizer {
UIImageView *imageView = (UIImageView *)recognizer.view;
switch([imageView tag])
{
case 1:
//do your work
break;
.
.
.
.
case n:
}
}
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
for (UIImageView *thumbnail in imageArray) {
[thumbnail addGestureRecognizer:tapRecognizer];
}
[tapRecognizer release];
You can get the view from the property "view" of UIGestureRecognizer.
In your selector, for example:
- (void)handleTap:(UITapGestureRecognizer *)recognizer {
UIImageView *imageView = (UIImageView *)recognizer.view;
// Now do something with your view
}
You cannot add a single tap recognizer to multiple views. Create a new one for every view you want to add a tap recognizer to. Since you are using a tableview just do that in the tableView:cellForRowAtIndexPath: method:
- (UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
// usual implementation
static NSString *cellIdentifier = #"CellIdentifier";
UITableViewCell *cell = [tableView dequeue ...];
if (!cell) {
cell = [[UITableViewCell alloc] init....];
// add new gesture recognizer here.
}
// setup cell: set the image (just an example)
cell.imageView.image = [images objectAtIndex:indexPath.row];
return cell;
}
Instead of using tags like mentioned in the other answers, and just getting the imageview try to work with the underlying model. When handling the tap, find the indexPath to know what model object to access:
- (void)handleTap:(UITapGestureRecognizer *)recognizer {
UIImageView *imageView = (UIImageView *)recognizer.view;
// assumes the image view is direct subview of the cell
// change to match your cell structure
UITableViewCell *cell = (UITableViewCell *) [imageView superview];
// get the index path for the cell clicked
NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];
// TODO: Use index path to get full image to display
}
This way you know the exact row of the image clicked, so you can access your model to get access to the full image to display.
You need to add tag to all images - thumbnail.tag = 100 for example.Then modify your selector to youSelector:(UITapGestureRecognizer *)sender;
In selector add switch
- (void) yourSelector:(UITapGestureRecognizer *)sender {
UIImageView *imageView = (UIImageView *)sender.view;
switch(imageView.tag) {
case 100: {
//This code will be handled if tag == 100;
}
}
}
Please try to subclass the ImageView & add the gesture recognizer to the subclass.
Now for each image create the ImageView object and add the image to that object.
Set some unique property so that you can identify which object click like the name of the image.
If My Story Board contains
View
|_my UIIMageView 1
|
|_my UIImageView 2
I can handle the touch down event by following the solution at this post
However, if my Story Board is changed to
Scroll View
|_my UIIMageView 1
|
|_my UIImageView 2
Now I can not detect the touch down event on one of these UIImageView...
Please help me on this issue..
I have used :
UITapGestureRecognizer *touch;
UIImageView *anImageView = [[UIImageView alloc] initWithFrame:CGRectMake(20, 20, 100, 100)];
anImageView.image = [UIImage imageNamed:#"iad.png"];
[anImageView setUserInteractionEnabled:TRUE];
anImageView.tag = 1001 ;
touch = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(test)] autorelease];
touch.numberOfTapsRequired = 1;
[anImageView addGestureRecognizer:touch];
[scrollView addSubview:anImageView];
[anImageView release];
- (void) test:(UIGestureRecognizer *)sender
{
UIImageView *imageView = (UIImageView *)sender.view;
switch (imageView.tag)
{
case 1001:
// your code
break;
case 1002:
// your code
break;
}
}
Probably not the answer you're looking for, but you should think about using UIButtons instead of UIImageViews.
Each UIButton have an UIImageView inside plus all the touch events with it.