I'm trying to add an event to a UIbutton:
UIButton *btn = [[UIButton alloc] init];
[btn setBackgroundImage:[UIImage imageNamed:#"aa.png"]
forState:UIControlStateNormal];
[btn addTarget:self
action:#selector(Presed:)];
and I'm getting this warning :
"UIButtom may not respond to addTarget:action"
The interface I'm creating this button for inherits from CDVPlugin
what's wrong with my code?
you are calling a method that is not declared.
it should be.
– addTarget:action:forControlEvents:
[btn addTarget:self action:#selector(Presed:)
forControlEvents:UIControlEventTouchUpInside];
Related
I have to create a same button in every ViewController. So i decided to write a class having this functionality once. I have created a class name MyUtils and added a back button to UINavigationItem and it displays correctly but don't know how to add an event to it in that class.
It displays accurately but no event is perform. I mean popViewControllerAnimated:YES
I call myUtil like
MyUtil *utils = [[MyUtil alloc] init];
[utils NavAndBackBtn:self.navigationItem];
MyUtil.m
-(void)NavAndBackBtn:(UINavigationItem *)nav
{
UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
[btn setImage:[UIImage imageNamed:#"icon_back.png"] forState:UIControlStateNormal];
//[btn setTarget:self action:#selector(popView) forControlEventTouchUPInside];
[button setFrame:CGRectMake(0,0,36,20);
UIBarButtonItem *barbtn = [[UIBarButton alloc] initWithCustomView:btn];
nav.leftBarButtonItem = barbtn;// this gives error
}
-(void)popView
{
// [self.navigationController popViewControllerAnimated:YES]; //not working no method in self
}
But don't know how to add an event to popViewControllerAnimated:YES in MyUtil class. because i don't have the reference of self there.
popView method
there must be a way to get the context of the class . i mean self in this class. and add event on its behalf. And there is no method of UINavigationItem which will popViewController.
In Simple Words
I simply want to popViewController event on that button which i created in MyUtils . But it must be implemented in MyUtils class. How can i popViewControllerAnimated in another class.
-(void)showBackBarButton:(UIViewController*)controller{
UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
[btn setBackgroundColor:[UIColor redColor]];
[btn setTitle:#"Back" forState:UIControlStateNormal];
[btn addTarget:controller.navigationController action:#selector(popViewControllerAnimated:) forControlEvents:UIControlEventTouchUpInside];
[btn setFrame:CGRectMake(0,0,36,30)];
UIBarButtonItem *barbtn = [[UIBarButtonItem alloc] initWithCustomView:btn];
controller.navigationItem.leftBarButtonItem=barbtn;
}
On ViewDiDLoad
[utils showBackBarButton:self];
I am trying to set the UIImage for a UIButton via the following code, but nothing happens. I am setting these inside viewDidLoad. The only way it shows up is if I use storyboard and set the image that way.
- (void)viewDidLoad
{
...
[self.locateMeButton setFrame:CGRectMake(11, 11, 46, 46)];
[self.locateMeButton setImage:[UIImage imageNamed:#"locateme_disabled.png"] forState:UIControlStateDisabled];
[self.locateMeButton setImage:[UIImage imageNamed:#"locateme_active.png"] forState:UIControlStateHighlighted];
[self.locateMeButton setBackgroundImage:[UIImage imageNamed:#"locateme_normal.png"] forState:UIControlStateNormal];
...
}
UIButton *aboutBtn = [UIButton buttonWithType:UIButtonTypeCustom];
[aboutBtn addTarget:self action:#selector(showAboutPage) forControlEvents:UIControlEventTouchUpInside];
[aboutBtn setTitle:#"About Me" forState:UIControlStateNormal];
[aboutBtn setFrame:CGRectMake(80.0, 120.0, 162.0, 42.0)];
[aboutBtn setBackgroundImage:[UIImage imageNamed:#"locateme_normal.png"] forState:UIControlStateNormal];
[aboutBtn setBackgroundImage:[UIImage imageNamed:#"locateme_disabled.png"] forState:UIControlStateHighlighted];
I had a similar problem. It turned out in my case that I was recreating the toolbar so the wrong toolbar object was being used. (Was trying to access a button on the wrong toolbar). Basically it seems a good idea to just check systematically that your methods are acting on all the receivers you expect and are being passed parameter values that you would expect.
I am creating a custom button with its own image, and assigning it to the rightbarbutton of a nabvigationcontroller I have. The problem is that when the user clicks on the button I get an exceptoin about my controller not recognizing that selctor??
UIImage* image1 = [UIImage imageNamed:#"someImage.png"];
CGRect imgRect = CGRectMake(0, 0, image1.size.width/1.8, image1.size.height/1.8);
UIButton *myButton = [[UIButton alloc] initWithFrame:imgRect];
[myButton setBackgroundImage:image1 forState:UIControlStateNormal];
[myButton addTarget:self action:#selector(nextScreenButtonAction) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *barButton =[[UIBarButtonItem alloc] initWithCustomView:myButton];
[self.navigationItem setRightBarButtonItem:myButton];
self.navigationController.navigationBarHidden = false;
May be this is the problem nextScreenButtonAction change it to
[myButton addTarget:self action:#selector(nextScreenButtonAction:) forControlEvents:UIControlEventTouchUpInside]
In your method definition you be passing and argument like
-(IBAction) nextScreenButtonAction:(id)sender
{
}
so in the addTarget you need to specify a colon(:) to indicate parameter
In response to below code,
[myButton addTarget:self action:#selector(nextScreenButtonAction) forControlEvents:UIControlEventTouchUpInside];
Make sure that you have create method in the same class like,
- (void) nextScreenButtonAction
{
// write your logic here...
}
I have created a springboard like panel containing buttons as follows:
-(void)configurePanel{
self.criteriaPanel.scrollEnabled=YES;
self.criteriaPanel=[[UIScrollView alloc] initWithFrame:CGRectMake(
0.0f,
0.0f,
[UIScreen mainScreen].bounds.size.width,
(BUTTON_HEIGHT+(3*BUTTON_Y_OFFSET))
)];
UIView *scrollViewContent=[[UIView alloc]init];
NSArray *criteriaTypeButtonTitles=[NSArray arrayWithObjects:
#"Option1",
#"Option2",
#"Option3",
#"Option4",
#"Option5",
#"Option6",
nil
];
for (int i=0; i<[criteriaTypeButtonTitles count]; i++) {
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.tag=i;
button.frame = CGRectMake(
(((BUTTON_X_OFFSET*i)+(BUTTON_WIDTH*i))+BUTTON_X_OFFSET)
, BUTTON_Y_OFFSET
, BUTTON_WIDTH
, BUTTON_HEIGHT
);
[button setTitle:[criteriaTypeButtonTitles objectAtIndex:i] forState:UIControlStateNormal];
[button setTitleColor:[UIColor blueColor] forState:UIControlStateHighlighted];
button.titleLabel.font=[UIFont systemFontOfSize:13.0f];
[button setBackgroundColor:[UIColor grayColor]];
[button.layer setCornerRadius:10.0f];
[button.layer setBorderWidth:1.0f];
[button addTarget:self action:#selector(sortByButtonTap:) forControlEvents:UIControlEventTouchDown];
[scrollViewContent addSubview:button];
}
//based upon # of buttons
self.criteriaPanel.contentSize=CGSizeMake(
(([criteriaTypeButtonTitles count]*BUTTON_WIDTH)+([criteriaTypeButtonTitles count]*BUTTON_X_OFFSET)),
(BUTTON_HEIGHT+(2*BUTTON_Y_OFFSET)));
[self.criteriaPanel addSubview:scrollViewContent];
[self.view addSubview:self.criteriaPanel];
}
The panel displays correctly and scrolls, but the tap events (sortByButtonTap:) for the buttons are never called. I suspect this is related to the buttons being contained in a view which is contained in the scrollview. After reading a number of other questions and the docs I still can't figure out what the solution should be.
EDIT:
I experimented w/ adding the buttons to the UIScrollView (self.criteriaPanel) directly and the button taps call sortByButtonTap: so it is something to do w/ the buttons being in the scrollViewContent.
You might need to set userInteractionEnabled on the containing view scrollViewContent for the button to receive touch events:
[scrollViewContent setUserInteractionEnabled:YES];
What if you try:
[button setExclusiveTouch:YES];
Buttons tend to work abnormally when they are inside a view that also handles touch events.
Follow this code for your query,
Add UIButton in Scrollview
scrollview.pagingEnabled = YES;
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake();
[button setTitle:#"X" forState:UIControlStateNormal];
[button setTitleColor:[UIColor clearColor] forState:UIControlStateNormal];
[button addTarget:self action:#selector(btnCloseClicked:withEvent:) forControlEvents:UIControlEventTouchUpInside];
[button addTarget:self action:#selector(btnCloseDraged:withEvent:) forControlEvents:UIControlEventTouchDragInside];
[button addTarget:self action:#selector(btnCloseDragedEnd:withEvent:) forControlEvents:UIControlEventTouchDragExit];
[scrollview addSubview:button];
scrollview.userInteractionEnabled = YES;
you can put this three methods of button manually.
Let me know if you still have query.
instead of:
[button addTarget:self
action:#selector(sortByButtonTap:)
forControlEvents:UIControlEventTouchDown];
try:
[button addTarget:self
action:#selector(sortByButtonTap:)
forControlEvents:UIControlEventTouchUpInside];
I think your problem is just that you set the wrong UIControlEvent to the UIButton. Change from UIControlEventTouchDown to UIControlEventTouchUpInside. If you connect a UIButton inside the Interface Builder it will always set it to this UIControlEvent:
Another reason:
Otherwise your UIScrollView controls the interactions because it needs to know if you want to scroll it. If you place UIButtons inside your UIScrollView they will be accessible but always with a little delay. This is why you should maybe change the settings for the UIScrollView:
You can disable delays content touches and UIButtons will be accessible immediately
I've managed to create a simple rounded rect button in Xcode through code but I'm having a little trouble actually getting it to do more what I want.
Ideal situation is a custom button type with image in both states as image.png linking to a URL (say www.google.com) can anyone help me out? I presume I need to write a method to do the link. That I can handle, just not sure how to hook it up without Interface Builder (targetting iOS)
Existing Code
UIButton * btn = [UIButton buttonWithType:UIButtonTypeCustom];
[btn addTarget:self action:#selector(supporturl) forControlEvents:UIControlEventTouchDown];
btn.frame = CGRectMake(20, 20, 150, 50);
[btn setTitle:#"Support and Help" forState:UIControlStateNormal];
[self addSubview:btn];
UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(20.0f, 20.0f, 150.0f, 50.0f)];
[btn setTitle:#"Support and Help" forState:UIControlStateNormal];
[btn setImage:[UIImage imageNamed:#"image.png"] forState:UIControlStateNormal];
[btn addTarget:self action:#selector(openWebPage) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:btn];
[btn release];
and in function
-(void) openWebPage
{
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:#"http://www.google.com"]];
}