What is the point of ever setting a button as an outlet? I am following a tutorial and the teacher didn't really mention why he set a button as an outlet. A button is suppose to do an action/call a method and so we set it as an IBAction.
He sets the button as an outlet and then proceeds to change the text of the button through Xcode in viewDidLoad, but why not just keep it as an IBAction and change the text by using setTitle: forState:UIControlStateNormal ?
Isn't a button suppose to cause an action by definition?
in some logic cases you would need to change the behaviour of the button , e.g. upon invoking an action (triggered by other event )you will need to disable it or change its backgroundColor or text.
you don't have to set at all times , but in many cases it is really useful
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I am trying to drag-drop a single radio button from object library in cocoa. But there is "radio group" object is available to drag-drop. In radio group has two radio button.
Is there any way to create a single radio button in cocoa application or hide the one radio button from radio group?
Thanks
You can make it one by going to attribute inspector and set the cell count to 1. but you have to handle the behaviour by your self logically.
Single radio button is not available in object library in cocoa. You can just use a normal UIButton and give its normal and selected images in Interface Builder.
Alternatively, you can just use a custom library for radio button like this one : https://github.com/onegray/RadioButton-ios
You should use a simple UIButton.
You can set different texts/images depending on a button status, like Devanshi suggested. The if/else approach is a bad idea though, because cocoa already provides these and are much more simple and small.
There are two ways, either storyboard (if you use it) or programatically, wherever you create your button (most likely viewDidLoad).
If you are using Storyboard
Storyboard is pretty straightforward, select your button, and under the "State" you can chose different settings. Each settings will actually load different parameters for the next settings. Like the title and image for example.
Just go on state "default" and set an unchecked box as image.
(You can)go on state "Highlighted" and set a temporary highlighted box as image; this is not mandatory.
Then go on state "Selected" and set a checked box as image.
And you're done.
If you are using only code
The programatic way to do this is fairly simple.
I assume we have a button called btSend,
UIControlStateNormal, UIControlStateSelected, UIControlStateDisabled, UIControlStateHighligted, are the states you can use. I used disabled and normal (enabled) here.
[self.btSend setImage:[UIImage imageNamed:#"SendIcon.png"] forState:UIControlStateNormal];
[self.btSend setImage:[UIImage imageNamed:#"SendIconGrayed.png"] forState:UIControlStateDisabled];
With this, you'll be up and running too.
After setting that up
Now that your buttons know what to show depending on their state, you need to add a selector method for your action (an IBAction), in which you will need to invert the state of your current button. You probably already have that, just add a boolean.
checkBoxSelected is a boolean that I created as an instance variable (on top of .m file). You can set it to "NO" in viewDidLoad if your radio is not selected by default, and to YES if it is selected by default.
#implementation TermViewController{
BOOL checkBoxSelected;
}
here is the method that is called when I press the button
- (IBAction)tapRadioButton:(id)sender {
checkBoxSelected = !checkBoxSelected;
[_btCheckbox setSelected:checkBoxSelected];
}
You probably have "something" that checks if your checkbox is selected, to know that, you can either get the state of your button by using self.yourButton.state. This will return a UIControlState, just check if it's Normal or Selected or Disabled or HIghlighted.
Or you can check the Boolean "checkboxselected" if it's YES or NO :)
If you have many radio buttons, you can save all those boolean values in a dictionary. the key would be your button number for example, and the object would be YES or NO. if you press the button, (like shown before), change the button state and also change it in the dictionary. At the end you have all your states in the dictionary.
I didn't explain all that in my first writing because that wasn't really a part of your question :) I hope this helps.
For radio button can use simple UIButton and maintain state of it and replace the image of on click event.
1) Declare globally in view
BOOL isChecked;
2) On button click event
if (isChecked)
{
[_btnRadioBox setImage:[UIImage imageNamed:#"chk_uncheck.png"] forState:UIControlStateNormal];
}
else
{
[_btnRadioBox setImage:[UIImage imageNamed:#"chk_check.png"] forState:UIControlStateNormal];
}
isChecked=!isChecked;
3) And get the status of it.
if (isChecked)
{
// Here write code of radio button when selected
}
else
{
// Here write code of radio button when unselected
}
You can use MVRadioButton to add animated radio button in iOS. This is very simple Drop in and easy to integrate Custom Control.
Its using CoreAnimation and Layers to Give it look and feel exactly like a Traditional Radio button that we have seen on Web.
Inside my .xib, I've placed an NSColorWell inside an NSView, and connected an IBAction in the controller to the NSColorWell's Sent Actions (via File's Owner). I figured I would respond to a click in my controller and send activate to bring up the NSColorPanel.
But unlike other my controls, I'm not getting the IBAction called. Clicking invokes a drag action on the color. I noticed this control doesn't derive from NSActionCell (like all my other controls). What's the proper control that is supposed to be used to both display a color and invoke the NSColorWell when clicked?
(note: this is Xcode/IB 3.2.x)
You listed both osx and ios in the tags, but I'm guessing this is an OS X problem.
There is a "Bordered" checkbox in IB's Attributes Inspector for NSColorWell. This toggles between a button-style color well, which is what you're asking for, and a color well which you can only drag a color swatch from. Make sure that's checked and you'll get the action like you're expecting.
I have a toolBar and I have setup two UIBarButtonItem on it. Both UIBarButtonItem are containing UIButtons as their customViews.
I activate a popover for their Touch Up Inside event as below,
[popover1 presentPopoverFromBarButtonItem:buttonItem1 permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
I have another UIButton named clearFilters inside the main view. (Also this is the view which is containing the above toolBar.) I have declared a method for clearFilters button's Touch Up Inside event.
My problem is,
I can not interact with the clearFilters button while a popover is active. So, I'm looking for a solution to interact with this clearFilters button, while a popover is active.
I tried by adding passthroughViews property for a popover as below and it do not work as I expect.
popover1.passthroughViews = [NSArray arrayWithObject:clearFiltersButton];
What could be the reason. As the documentation has mentioned I can not see any issue.
I expect if the above things are correct, then the Touch Up Inside event of the the clearFilters button's should be fire up.
So, please show me if there is any issue or a necessary way to work on this thing.
I'm working on XCode4 and iOS 4.3.
Thanks.
The UIPopoverController documentation reveals why the other bar buttons can be tapped while the popover is visible:
“When presenting the popover, this method adds the toolbar that owns the button to the popover’s list of passthrough views.”
Try querying and logging the popover’s passthrough views. Does it already have things in it? Perhaps something like this would work?
myPopover.passthroughViews = [myPopover.passthroughViews arrayByAddingObject:clearFilters];
I haven’t tested this code, but it’s worth a try.
There is no Done button on a Number Pad-type keyboard. I don't want to add a custom Done button, but how do I dismiss the keyboard?
You could add a UINavigationBar/UIToolBar with a done button(a UIBarButtonItem), and make the textField/textView resignFirstResponder on the done button's action.
You can add the UINavigationBar/UIToolBar as inputAccessoryView of textField/textView.
textField.inputAccessoryView = aNavBarWithDoneButton;
Edit: Availability iOS (3.2 and later)
The simplest solution is to add a new button somewhere in your UI that calls resignFirstResponder on your UITextField (or whatever) when tapped. Putting this in a toolbar is problematic on iPhone because toolbars are typically at the bottom of the screen and obscured by the keyboard.
A slightly more complex solution is to put an invisible UIView behind all of your other tappable UI elements. Any taps not handled by your existing UI will go to this new view, which can call resignFirstResponder on your text field.
If neither of these sound appealing, perhaps you should expand your question to include the type of behavior you want.
I want to show a total inside a toolbar. I put in IB the UILabel on top of the toolbar .
However, when I run the app, the UILabel is totally invisible (but can set values on code fine).
The most bizarre thing is that in other form, all work fine. I don't see why in one form work but not in another...
Any idea in how fix this? Or why is this behaviour happening?
Don't use a UILabel.
Use a UIBarButtonItem. Then set it to style: plain. It looks like a label, but it actually borderless button. This is the general practice of displaying text on a bar.
You can also create UIBarButtonItem with a custom view in code. You are simple "wrapping" the UILabel in a UIBarButtonItem allowing you to add anything you want to a tool bar.
To add in response to comment:
Either way, you make the button "inactive" and it doesn't respond to touches. Even though it is a button, it doesn't appear to be one. This is how Apple expects to add views to a toolbar/navbar as apposed to "float things on top of it". It violates no HIG guidelines, much the opposite, it is a reccomended design technique.
To stop the glow:
Create the button programmatically, make sure it is disabled, add it to the bar, it should then be disabled, but not dim.
In IB, have you tried to select the label and use the "Bring to Font" menu item (under Layout)? It seems like you are trying to do something pretty standard.
When you try to set values, is the label coming up as nil or at address 0x0? It's possible that the label is there, but its text cannot be set because its instance is faulty (not properly connected in IB to the IBOutlet).... Just put a breakpoint on the line where you are trying to set the value(s) for the label, and verify that the label variable is not nil (or 0x0). If it's not, try setting the text and verify on the next line that its text was set properly.
drag a UIButton into your UIToolBar. Then uncheck User Interaction Enables for this button.
Customize your UIButton so that it will look like a UILabel. Hope this will help you.