Good Evening all!
I have some UIButtons added dynamically into my view and of course I have an IBAction which handles button events.
The problem is: How can I detect which button is pressed if the only thing I know is the (id)sender and the array of buttons?
Buttons are never the same, every button has a different behavior. When I want to use static buttons and connect them through the IB I use something like this :
-(IBAction)doSomething:(id)sender
{
if(sender == button1)
dosomething;
if(sender == button2)
dosomething else;
if(sender == button3)
dosomething3;
}
In my case this does not work because there is no button1, button2, button3 but a MutableArray of buttons which have the same name as they were allocated with it. Button!
I tried using the way above but with no success and i tried also getting the tag of a button but I have nothing to compare it to!
I would really appreciate your help.
sincerely
L_Sonic
PS Dynamicaly means that i am creating the buttons in random time during run time like this
-(void)configActionSheetView
{
buttonView = [[UIView alloc]initWithFrame:CGRectMake(0.0,460, 60, 480)];
[buttonView setBackgroundColor:[UIColor blackColor]];
[buttonView setAlpha:0.6];
for (int i = 0 ;i<[buffButtons count];i++)
{
UIButton *customButton = [buffButtons objectAtIndex:i];
customButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
//UILabel *customLabel = [[UILabel alloc]init];
//[customButton setTag:(i)+11];
[customButton addTarget:self action:#selector(activateBuffEffect:) forControlEvents:UIControlEventTouchUpInside];
[customButton setAlpha:1.0];
customButton.frame = CGRectMake(8.0, 5+(50*i), 44.0, 44.0);
[customButton setTitle:nil forState:UIControlStateNormal];
buttonView.frame = CGRectMake(0, 460, 60, 50+(44*(i+1)));
[buttonView addSubview:customButton];
}
}
this is inside a functions and gets called during run time. the buffButtons is a mutableArray with buttons that gets populated during runtime.
i need a solution like this i cannot get a different eventhandling method for everybutton.
When you was "added dynamically" I assume you mean that they are created from some piece of code. Since all buttons to different things and you know what a certain button should do, why don't you add different actions to different buttons?
UIButton *myCreatedButton = [[UIButton alloc] init];
[myCreatedButton addTarget:self
action:#selector(doSomething:)
forControlEvents:UIControlEventTouchUpInside];
UIButton *myOtherCreatedButton = [[UIButton alloc] init];
[myOtherCreatedButton addTarget:self
action:#selector(doSomethingElse:)
forControlEvents:UIControlEventTouchUpInside];
In the above code the target (set to self) is the class where the method you want to run is found, the action is the method that you want to run and the controlEvent is what should cause the method to run.
If you did it like this you would split the code in different methods like these (you do not need to specify them in the header):
-(void)doSomething:(id)sender {
// do somthing here ...
}
-(void)doSomethingElse:(id)sender {
// do somthing else here ...
}
This way you don't need to know what button was pressed since the correct code would get called anyway. Besides it makes it cleaner if you need to change the code for some of the buttons.
Found it!
-(IBAction)buttonTapped:(id)sender {
UIButton *btn = (UIButton *)sender;
NSLog(#"tapped: %#", btn.titleLabel.text);
[self anotherIBAction:sender];
}
now i can get the tag from the btn :D
thnk you!
Why not add a tag the button and then get the tag number from (id)sender in the selector function?
Related
I have created 3 UIbuttons on the top of the screen. Now after clicking every button I got the 5 buttons for each at below with different background images. Below is the code for my first button(located at top) by which I got 5 images in my view controller.
-(IBAction) btnforimages1click:(id)sender {
for (int a=0; a<5 ; a++) {
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad )
{
buttonsforbundle1 = [[UIButton alloc]initWithFrame:CGRectMake(100*a,300 ,100 ,90 )];
[buttonsforbundle1 addTarget:self action:#selector(btn4images1:) forControlEvents:UIControlEventTouchUpInside];
buttonsforbundle1.tag = a;
[buttonsforbundle1 setBackgroundImage:[UIImage imageNamed:[bundle1 objectAtIndex:a]] forState:UIControlStateNormal];
[self.view addSubview:buttonsforbundle1];
}
}
I do the same for other two buttons also. Now here I want is, when I click any of my top 3 buttons
I just want to display the related buttons (created in for loop)
I want to hide the other buttons related to other Top most buttons.
Please suggest me how to solve this.
You have at least three options:
1) Access UI element by tag:
If you can manage to issue unique tag number in your btnforimages1click, btnforimages2click, btnforimages3click for your other 5 added UIButtons, then you can access them:
UIButton *button = (UIButton *)[self.view viewWithTag:99];
[button removeFromSuperview];
2) Keep reference of the created buttons:
// in view.h
NSMutableArray *my_created_buttons;
...
// in view init
[[my_created_buttons alloc] init];
...
-(IBAction) btnforimages1click:(id)sender {
for (UIButton *b in my_created_buttons {
[b removeFromSuperview];
}
if([my_created_buttons count]) {
[my_created_buttons removeAllObjects];
}
... let buttonsforbundle1 local variable since we store current 5 button set in array
UIButton *buttonsforbundle1;
... in your for loop add this after creating and adding to view
[my_created_buttons addObject:buttonsforbundle1];
}
You can further refactor these code eg. by making mutablearray management to other method.
3) Keep it in Interface Builder
I think it is the easiest option, create 5 UIButtons in Interface Builder and have 5 IBOutlet for them. Then in your btnforimages1click you can eg:
-(IBAction) btnforimages1click:(id)sender {
self.IBbutton1 setBackgroundImage[UIImage imageNamed:[bundle1 objectAtIndex:0]] forState:UIControlStateNormal];
self.IBbutton2 setBackgroundImage[UIImage imageNamed:[bundle1 objectAtIndex:1]] forState:UIControlStateNormal];
self.IBbutton3 setBackgroundImage[UIImage imageNamed:[bundle1 objectAtIndex:2]] forState:UIControlStateNormal];
self.IBbutton4 setBackgroundImage[UIImage imageNamed:[bundle1 objectAtIndex:3]] forState:UIControlStateNormal];
self.IBbutton5 setBackgroundImage[UIImage imageNamed:[bundle1 objectAtIndex:4]] forState:UIControlStateNormal];
}
So you don't hide them, just change the background image. Moreover you don't have to deal with different touchUpInside event, use only one method, and in that one click method, you can distinguish between the different clicked UIButton by checking their tag (plus you have to use a variable to check which of the 3 top UIButton was clicked).
Here's my code (it's wrapped in an IBAction that is called when the button is pressed):
if (myButton.currentTitle == #"test") {
[myButton setTitle:#"test2" forState:UIControlStateNormal];
}
if (myButton.currentTitle == #"test2") {
[myButton setTitle:#"test" forState:UIControlStateNormal];
}
I want the UIButton text to toggle when pressed (if text = "test" then change to "test2" and when pressed if text = "test2" change to "test").
I do have an IBOutlet connected for myButton and the the IBAction connected to myButton--so I am pretty sure it isn't a problem with my connections.
For some reason this isn't working, I'm sure I am missing something very simple.
use isEqualToString: instead of ==
This is because you lack a control statement that skips the second if when the first one succeeds. When you come into the block with "test", you switch it to "test2", and then the second condition succeeds immediately, and you turn "test2" back into "#test".
You can an an else to fix this, but you can skip the if altogether by using an NSArray that maps the current state to the new state.
// This should be made static, and initialized only once
NSDictionary *nextTitle = [NSDictionary dictionaryWithObjectsAndKeys:
#"test", #"test2", #"test2", #"test", nil];
// This line does the toggling
[myButton setTitle:[nextTitle valueForKey:myButton.currentTitle] forState:UIControlStateNormal];
if ([myButton.currentTitle isEqualToString:#"test"]) {
[myButton setTitle:#"test2" forState:UIControlStateNormal];
}
if ([myButton.currentTitle isEqualToString:#"test2"]) {
[myButton setTitle:#"test" forState:UIControlStateNormal];
}
Hope, this will help you...
Comparing user-visible strings is generally considered bad practice (and becomes tedious when you need to do i18n), especially with string literals since it's vulnerable to typos.
If you're just going to toggle between two states, the easiest thing to do is to use the UIControl.selected property (corresponding to UIControlStateSelected):
// In init
[myButton setTitle:#"test" forState:UIControlStateNormal];
[myButton setTitle:#"test2" forState:UIControlStateSelected];
[myButton setTitle:#"test2" forState:UIControlStateSelected|UIControlStateHighlighted];
// Toggle
myButton.selected = !myButton.selected;
It also makes the code a lot cleaner when you when you decide to toggle the button image/background/text colours too.
Note the slight gotcha: If you don't set the title for UIControlStateSelected|UIControlStateHighlighted it will use the title for UIControlStateNormal when the button is both selected and highlighted (touched).
When comparing strings to each other try using if([str1 compare:str2] == NSOrderedSame)
With a loop I add UIImageView to a UIScrollView i need to add an extra parameter addTarget so when i click i can log the index.
[imageButton addTarget:self action:#selector(buttonPushed:)
forControlEvents:UIControlEventTouchUpInside];
-(IBaction) buttonPushed: (int) index
{
NSLog(#"%d",index);
}
How do i achieve this?
When you add a target, the method being call can either have no arguments (e.g. buttonPushed) or have one (buttonPushed:) which is the control sending the event (in this case your button). If you want an index, or any other value, you need to set it on the button sending the event. For example, when you setup the buttons:
myButtons = [NSArray arrayWithObjects:myFirstButton, mySecondButton, nil];
[myFirstButton addTarget:self action:#selector(buttonPushed:)
forControlEvents:UIControlEventTouchUpInside];
[mySecondButton addTarget:self action:#selector(buttonPushed:)
forControlEvents:UIControlEventTouchUpInside];
and implement your action as
- (IBaction)buttonPushed:(UIButton *)button
{
NSLog(#"%d",[myButtons indexOfObject:button]);
}
Use the tag property of the button
i am having a application where i am generating the uibuttons dynamically want to use same #selector...Now as sooon as event is generated i wanna check for values and pass it to thtroughthat selector how can i implement this code?
can anyone tell me a tutorial sort where buttons are dynamically generated and check for particular button click is depicted?
Plz help...
Not sure what do you call "dynamically"... Objective-c objects are always created dynamically. Perhaps you mean situation where you want to create series of very similar buttons with same code? Yes, it is quite a common task. For example in calculator like app, we need ten buttons with digits, why not create them with single block of code ? So:
- (void)makeButtons{
UIButton * aButton;
for(int i = 0; i < 10; i++){
aButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
aButton.frame = CGRectMake(0, i*45, 60, 40);
[aButton addTarget:self action:#selector(digitClick:) forControlEvents:UIControlEventTouchUpInside];
[aButton setTitle:[NSString stringWithFormat:#"%d",i] forState:UIControlStateNormal];
aButton.tag = i;
[self.view addSubview:aButton];
}
}
- (void)digitClick:(id)sender{
UIButton * aButton =(UIButton *)sender;
NSLog(#"cliced button with title %d",aButton.tag);
}
we use a tag property to find index of clicked button, it is often used way, but there are some other ways. For example store created buttons in array and then check if sender is equal to one of array elements:
...
if ([allButtons objectAtIndex:i] == sender)
...
If you want to pass some data, for example string from each button just create array with these objects and then access it using tag as index.
Try:
[self.button1 addTarget:self action:#selector(buttonTouchDown:) forControlEvents:UIControlEventTouchDown];
[self.button2 addTarget:self action:#selector(buttonTouchDown:) forControlEvents:UIControlEventTouchDown];
- (IBAction)buttonTouchDown:(id)sender
{
if (sender == self.button1) NSLog(#"Button-1");
if (sender == self.button2) NSLog(#"Button-2");
}
I am trying to figure out the code for clearing multiple text fields at once. I know that there is another question like this with answers but could I get a little more information or code examples. I have 16 text fields in my app.
Thanks
Check out the UITextFieldDelegate methods, specifically, textFieldShouldClear. This is called when someone taps the little x in the text field. I am going to give you a way to clear all textfields when one of those is tapped or any other button is tapped
- (void)clearAllTextFields {
for (UITextField *textField in [self textFields]) { //textFields is an rray that is holding pointers to your 16 text fields
[textField setText:nil];
}
}
If you want this to happen on a button press or something, add it as a target. Here is how you would do it if one of the x's in the fields are tapped:
- (BOOL)textFieldShouldClear:(UITextField *)textField {
[self clearAllTextFields];
return YES;
}
UPDATE:
UIButton *button = [[[UIButton alloc] initWithFrame:CGRectMake(0,0,100,44)] autorelease];
[button setTitle:#"blah forState:UIControlStateNormal];
[button addTarget:self action:#selector(clearAllTextFields) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button];