Obj C - Checking Current State of a Disclosure Arrow - objective-c

I'm trying to differentiate between a disclose arrow being 'On' (pointed down) or 'Off' (pointed up). The posted code is completely wrong and just the general idea of what I want it to do.
- (IBAction)disclosureArrow:(NSControl *)sender{
if (disclosureArrow currentState:ON) {
//action
}
IBOutlet id discloseArrow is attached to the disclose button in interface builder and it receives a command from IBAction that is also attached to the button. How do I check the button's current state ? (In regards to disclosure arrows.)

I believe:
BOOL isOn = ([sender state] == NSOnState);
Should do the trick.

So you have set a custom image as button as your accessory view of a tableViewCell? Is that correct? Are you using static cells? How do you change the arrows?
The most easy way is probably to change the tag of your button regarding to its state. When assigning the arrow up, you give it the tag 1. Else you give it the tag 2.
Than you could read it like that:
- (IBAction)disclosureArrow:(NSControl *)sender
{
if (sender.tag == 1)
{
}
}

Related

UIButton remove style selected state

I would like to remove the selected state effect from the UIButtons.
When pressed a blue capsule appears next to the UIButton.
UPDATE with new problem
UIButton with type:system selects the targeted button. After changing the UIButton type to custom. This effect was removed. Other buttons were pressed that are located in the same view.
This is part of the UIButton function, if pressed it should run the code in this IBAction. Two UIButtons are connected to this function. With type system it selected the right UIButton, with type custom it seems to select at random.
- (IBAction) buttonAction:(id)sender
{
UIButton *btn = sender;
btn.selected = !btn.selected;
if([sender tag] == 1){
// run code UIButton 1
}
if([sender tag] == 2){
// run code UIButton 2
}
}
I hope this is clear.
Select the button from the xib file and change its type to custom in attributes inspector.
I found the solution to the second problem I described.
The UIButton type: custom doesn't have the selected trait as default.
The traits that were selected are: Button and User Interaction Enabled.
After selecting: selected it worked.
traits

NSWindow, press key ENTER: how to limit the key listening to the focused NSControl?

I have an NSWindow with a main "OK" button. This button has as "key equivalent" property in interface builder, the key ENTER i.e ↵.
It works good, but now I have a new NSComboBox, which is supposed to invoke a method when the user selects a list item, or he preses Enter / ↵.
However, when I press Enter, the main Button receive the notification and the window close. How to prevent this?
This is the normal behavior what you are getting, but you can hack a bit, by removing and adding the key-equivalent.
Add following delegates of NSComboBox:
- (void)comboBoxWillPopUp:(NSNotification *)notification;{
[self.closeButton setKeyEquivalent:#""];
}
- (void)comboBoxWillDismiss:(NSNotification *)notification;{
[self.closeButton setKeyEquivalent:#"\r"];
}
One way you can workaround for prevent enter notification is like that below:-
//Connect this action method to your combobbox and inside that set one BOOL flag to yes
- (IBAction)comBoxItm:(id)sender
{
self.isEnterCalled=YES;
}
//Now check this flag to your some method where close window is called
-(void)someMethod
{
//Check the flag value if it is yes then just ignore it
if (!self.isEnterCalled)
{
//Close window logic
}
self.isEnterCalled=NO;
}
Ran into the same problem. Had "hot key" which I'd like to switch off while editing some text fields. I found solution for myself. There's no need in override lots of NSTextField base methods.
Firstly, I removed all the "key equivalents". I used to detect Enter key down with the + (void)addLocalMonitorForEventsMatchingMask:(NSEventMask)mask handler:(NSEvent *(^)(NSEvent *))block class method of NSEvent. You pass block as a parameter, where you can check for some conditions. The first parameter is the event mask. For your task it would be NSKeyDownMask, look for other masks at the NSEvent Reference Page
The parameter block will perform each time the user pushes the button. You should check if it is right button pushed, and - generally - if the current window first responder isn't some editable control. For that purposes we need NSWindow category class just not to implement this code each time we deal with NSKeyDownMasked local monitors.
NSWindow+Responders class listing:
#interface NSWindow (Responders)
- (BOOL)isEditableFirstResponder;
#end
#implementation NSWindow (Responders)
- (BOOL)isEditableFirstResponder
{
if (!self.firstResponder)
return NO; // no first responder at all
if ([self.firstResponder isKindOfClass:[NSTextField class]]) // NSComboBox is NSTextField subclass
{
NSTextField *field=(NSTextField *)self.firstResponder;
return field.isEditable;
}
if ([self.firstResponder isKindOfClass:[NSButton class]]) // yep, buttons may be responders
return YES;
return NO; // the first responder is not NSTextField or NSButton subclass - not editable
}
#end
Don't know if there's another way to check if we are now editing some text field or combo box. So, there's at least the part you add the local monitor somewhere in your class (NSWindow, NSView, some controller etc.).
- (void)someMethod
{
id monitor=[NSEvent addLocalMonitorForEventsMatchingMask:NSKeyDownMask handler:(NSEvent *)^(NSEvent *theEvent){
if (theEvent.keyCode==/*Enter key code*/ && ![self.window.isEditableFirstResponder]) // you should check the key modifiers too
{
// your code here
}
return theEvent; // you may return the event to pass the key to the receiver
}];
}
Local monitors is safe remedy about the Apple rules. It works only inside your application. For global key down events you may use addGlobalMonitor but Apple may reject your app from the AppStore.
And don't forget to remove the monitor when there's no need in it.
- (void)viewControllerShutdownMethod
{
[NSEvent removeMonitor:monitor];
}
Good luck.

Enabling Done Button When User Changes Values - Xcode

I am trying to make it to where if any value is typed on the keyboard without hitting the return key and two of the labels have been changed from "Select" to something else, the button up at the top becomes enabled. However, I have tried using an IBAction saying:
- (IBAction)valuesChanged {
if (textField.text != nil && ![labelOne.text isEqualToString:#"Select"] && ![labelTwo.text isEqualToString:#"Select"]) {
NSLog(#"Success");
}
else {
NSLog(#"No Success");
}
}
But I have realized that this does not work because:
The textfield does not work when I put the IBAction Sent Event as "Value Changed"
The labels won't accept an action.
How do I go about doing this?
The text field delegate method that tells you that the user is typing a character in the text field or otherwise changing its contents is textField:shouldChangeCharactersInRange:replacementString:. Implement it in your text field delegate and respond as appropriate. You will also just return YES.
One reason your original code couldn't be hooked up might be that you have not used the canonical form of an IBAction method; it should be
- (IBAction)valuesChanged:(id)sender {
Another problem in your original code is that a UITextField does not emit Value Changed. What you wanted was Editing Changed. But the delegate method works just as well.
Try UITextField delegate methods.
- (void)textFieldDidBeginEditing:(UITextField *)textField;
- (void)textFieldDidEndEditing:(UITextField *)textField;

Toggle-style button : how to toggle title in this case?

I have a CoreData app presenting data with a TableView, textfields, buttons... It deals with people situations and one of the button is a toggle-style button with title "Close". When we consider the user's case closed, we press and it changes the state of a boolean-type attribute in the entity, representing the closed/open state of the case, using a simple binding to the attribute value. The button title also becomes "Reopen" as the case may be reopened in the future.
Then additional things had to be done with the data on pressing the button, so I had to create an IBAction method instead of simply use the former binding. Problem: when button is pressed, the action is done, but the button title is not toggled. It makes sense since nothing tells it to toggle anymore.
I decided to remove the action on the boolean from the IBAction and use again the value binding, so the boolean change is performed by the binding and the other operations are performed by the IBAction. Problem: it modifies the data unexpectedly, sometimes working fine, sometimes not doing all things in a coherent way as expected.
So I'm back with all changes handled by the IBAction and this time, I'm using the Title/Alternate title bindings instead of the value binding. Now the button title toggles, but instead of displaying the word "Close" and "Reopen", it displays the boolean values "0" and "1".
I should perhaps handle the button title change in the IBAction as well, using "setTitle", but then I see a new problem coming. On app start-up, how will it pick the appropriate entity record for reference? And what if the table is in a "No Selection" situation? Looks like a quite extensive piece of code to handle such a small issue...
Any advice on a short, more direct way of handling this is welcome. Thanks.
Sounds like you probably have a couple of different options.
This first option is a bit more involved than the others, but is still good to know for the record. This option basically would not use bindings for the close/re-open button, but instead, set the title, etc. programmatically. The basic game plan would be as follows:
The close/re-open button's initial title when the document opens is set in the nib file (e.g. Close).
Optionally, when the document opens, you could disable the button in -awakeFromNib, since the table view will have no initial selection.
The only actions that would necessitate the button's title or enabled state to be changed is 1) when the tableview's selection is changed, and 2) when you've clicked the close/re-open button to toggle the case's state.
To achieve the desired result, you'd create an IBOutlet to the close/re-open button if you don't already have one. You'd then connect up the tableview's delegate outlet to your controller class, which will let your controller class know when the tableview's selection has been changed (via the - (void)tableViewSelectionDidChange:(NSNotification *)notification <NSTableViewDelegate> protocol method). You would also need to update the close/reopen IBAction method to make sure it switches the title on the button after being clicked (since the tableview selection wouldn't change during that operation). The controller class's code might look something like this:
// add this declaration to avoid compiler warnings:
#interface LHController (LHPrivate)
- (void)updateCloseReopenButtonTitle;
#end
- (void)awakeFromNib {
[self updateCloseReopenButtonTitle];
}
- (void)tableViewSelectionDidChange:(NSNotification *)notification {
[self updateCloseReopenButtonTitle];
}
- (IBAction)toggleCloseReopenButton:(id)sender {
// do your existing code here and then add:
[self updateCloseReopenButtonTitle];
}
- (void)updateCloseReopenButtonTitle {
// assuming 'casesController' is an IBOutlet to your NSArrayController
NSArray *selectedObjects = [casesController selectedObjects];
// loop through the selected cases to determine whether
// they're all closed, all open, or mixed to set
// the title of the button appropriately
BOOL allClosed = YES;
for (LHCase *case in selectedCases) {
if ([case isOpen]) {
allClosed = NO;
break;
}
}
[closeReopenButton setTitle:(allClosed ? #"Reopen" : #"Close")];
[closeReopenButton setEnabled:[selectedObjects count] > 0];
}
Before bindings came along, this is how we used to have to do things.
Another option might be reconsidering your user interface: maybe rather than a push/toggle button whose title you need to toggle, you could instead just have a checkbox titled Closed, which would signify whether the selected cases were closed or not. You could use bindings for the checkbox's state, like shown in the image below:
You could then have an IBAction method that handles the extra stuff that needs processing. You can ask the casesController for the -selectedObjects and then loop through them. As long as you make sure the checkbox Allows Mixed states, it has the added advantage of better representing mixed-case scenarios, in case of a selection of cases with mixed open/closed states (the checkbox a dash instead of a full check).
Another option if you want to stick with a toggle button is to create and specify a custom NSValueTransformer for the title and alternate title bindings. This value transformer would take in the boolean closed/open state of the case and turn it into a string more fitting than just 0 or 1 (which is what's being displayed now). It might look something like this:
+ (Class)transformedValueClass {
return [NSString class];
}
+ (BOOL)allowsReverseTransformation {
return NO;
}
- (id)transformedValue:(id)value {
BOOL isClosed;
if (value == nil) return nil;
// Attempt to get a reasonable value from the
// value object.
if ([value respondsToSelector: #selector(boolValue)]) {
isClosed = [value boolValue];
} else {
[NSException raise: NSInternalInconsistencyException
format: #"Value (%#) does not respond to -boolValue.",
[value class]];
}
return (isClosed ? #"Reopen" : #"Close");
}

How to take text value of NSButton?

how should i take NSButton text value , e.g if i use 2 buttons with text Click and Cancel, i want to check which button is clicked and then show a message with NSRunAlertPanel(...) which button i have clicked..what code should i write for it when the button is clicked.
In you action method you get an argument, usually named 'sender', which is the button. So you could do something like:
- (IBAction)buttonClicked:(id)sender
{
if ([[sender title] isEqualToString:#"Click"]) {
NSLog(#"Click clicked.");
} else if ([[sender title] isEqualToString:#"Cancel"]) {
NSLog(#"Cancel clicked.");
}
}
It's better not to use the title for checking the button, since the title could change in different localizations. You could specify the tag instead, which is simply an int and which can be used to identify different senders.
The way this is typically implemented is that each button would call a different action, thus there would be no need to check the text of the button. See The Target-Action Mechanism.
In general it is almost always a bad idea to use the user visible text to control program logic because that makes localization harder.
You might also want to describe your situation further. Are you using Interface Builder to create your interface? Are these buttons in a modal dialog or a document window?
You could give the button a name in the class info tab of the inspector window in Interface Builder, then declare it as an IBOutlet in your app delegate.
AppDelegate.h:
IBOutlet NSButton *ClickButton;
IBOutlet NSButton *CancelButton;
Then hook up the outlet in Interface Builder, and just check to see which button is the sender in your method:
- (IBAction)buttonClicked:(id)sender
{
if (sender == ClickButton) {
NSLog(#"Click clicked.");
}
else {
NSLog(#"Cancel clicked.");
}
}