What is the best way to make a UIButton checkbox? - iphone

Question

I am trying to make a standard check box for my iPhone app from a UIButton with a title and image. The button image changes between an "unchecked" image and a "checked" image.
At first I tried subclassing UIButton but UIButton has no -init*** method to use in my -init method.
What is the best way to do this?
Thanks in advance.

Answer 1

You shouldn't need to subclass the UIButton class. By design, Objective-C favors composition over inheritance.
UIButton is a subclass of UIControl, which has a selected property. You can use this property to toggle the on/off behaviour of a checkbox, just the same way a UISwitch does.
You can attach an action to the button's touched up inside event, and perform the toggling in there, something like this:
// when you setup your button, set an image for the selected and normal states
[myCheckBoxButton setImage:checkedImage forState:UIControlStateSelected];
[myCheckBoxButton setImage:nonCheckedImage forState:UIControlStateNormal];
- (void)myCheckboxToggle:(id)sender
{
myCheckboxButton.selected = !myCheckboxButton.selected; // toggle the selected property, just a simple BOOL
}

Answer 2

Set the images in the button:
[button setImage:uncheckedImage forState:UIControlStateNormal]
[button setImage:checkedImage forState:UIControlStateSelected]
Now all you need to do is:
button.selected = state
and the correct images will display.

Answer 3

All you need to do is set 2 different images for the states UIControlStateNormal and UIControlStateSelected, then in your selector, changed the selected property of the button.
Here is a working example (replace image names with your own):
- (void)loadView {
// ...
UIButton *chkBtn = [UIButton buttonWithType:UIButtonTypeCustom];
[chkBtn setFrame:CGRectMake(0, 0, 300, 25)];
[chkBtn setImage:[UIImage imageNamed:#"UNCHECKED.png"]
forState:UIControlStateNormal];
[chkBtn setImage:[UIImage imageNamed:#"CHECKED.png"]
forState:UIControlStateSelected];
[chkBtn addTarget:self
action:#selector(chkBtnHandler:)
forControlEvents:UIControlEventTouchUpInside];
// Optional title change for checked/unchecked
[chkBtn setTitle:#"I am NOT checked!"
forState:UIControlStateNormal];
[chkBtn setTitle:#"I am checked!"
forState:UIControlStateSelected];
[self.view addSubview:chkBtn];
[chkBtn release], chkBtn = nil;
// ...
}
- (void)chkBtnHandler:(UIButton *)sender {
// If checked, uncheck and visa versa
[sender setSelected:!sender isSelected];
}

Answer 4

For anyone interested in the future - instead of doing it yourself just download the link below from GitHub and it has it subclassed from UIControl already and functions perfectly as a checkbox. Also includes a sample project on how easy it is to use:
https://github.com/Brayden/UICheckbox

Answer 5

I have used M13Checkbox in one of my projects. Works ok.
https://github.com/Marxon13/M13Checkbox

Answer 6

Did you try overriding the initWithCoder method, just in case it is loaded from a nib somehow?

Answer 7

UIImage* nonCheckedImage=[UIImage imageNamed:#"ic_check_box_outline_blank_grey600_48dp.png"];//[UIImage init
UIImage* CheckedImage=[UIImage imageNamed:#"ic_check_box_black_48dp.png"];//[UIImage init
//ic_check_box_black_48dp.png
[_checkBox setImage:CheckedImage forState:UIControlStateSelected];
[_checkBox setImage:nonCheckedImage forState:UIControlStateNormal];
}
- (IBAction)checkBoxToggle:(id)sender {
_checkBox.selected = !_checkBox.selected; // toggle the selected property, just a simple BOOL
}
the image you can use google icon

Answer 8

Try this:-
-(IBAction)clickCheckButton:(UIButton *)sender {
if (sender.tag==0) {
sender.tag = 1;
[sender setImage:[UIImage imageNamed:#"check.png"] forState:UIControlStateNormal];
}else
{
sender.tag = 0;
[sender setImage:[UIImage imageNamed:#"uncheck.png"] forState:UIControlStateNormal]; } } sender.tag = 0;
[sender setImage:[UIImage imageNamed:#"uncheck.png"] forState:UIControlStateNormal];
}
}

Answer 9

Why not use a switch - UISwitch? This is used to display an element showing the boolean state of a value.