I have a view with three NSTextFields connected to a View Controller that acts as delegate for all three of them.
I have successfully implemented the controlTextDidEndEditing to intercept the text entered by the user and change a property in my model. The method though is unique in the delegate and all the three textfields trigger it. The question is, how can I identify which one of them fired the notification? I can get the NSTextView from the key "NSFieldEditor" of the notification but that doesn't really tell me which one it is. At the beginning I thought of using the NSTextField placeholder but the the method returns me a NSTextView which doesn't seem to have a placeholder property.
Any idea?
You should be able to obtain the reference to the NSTextField via [notification object]. If all three of your NSTextFields are available as delegates, it is easy to check which one triggered the event.
Like this:
- (void)controlTextDidEndEditing:(NSNotification *)aNotification {
NSTextField* textField = (NSTextField *)[aNotification object];
if (textField == textField1) {
// textField1 triggered the event
} else if (textField == textField2) {
...
} else if (textField == textField3) {
...
}
}
Related
I have a TextField in my Cocoa application. This TextField will be sometimes filled and sometimes empty.
I want it so that when the field is empty a button is disabled. Now I check the field whenever I do some action with Core Data from where the TextField gets its value.
I'd like for it to always be checked for this.
If the user edits the text field and brings up the field editor then you can use the following.
You can implemented the NSTextFieldDelegate protocol (which is really just the NSControlTextEditing protocol). For example, in a controller or a delegate object implement the control:textShouldEndEditing: method and use this to check the values of the new string. If the string is empty then disable the button.
// In a control object which has a reference to the NSTextField and the NSButton
- (BOOL)control:(NSControl *)control textShouldEndEditing:(NSText *)fieldEditor {
if ([fieldEditor.string isEqualToString:#""])
{
[self.button setEnabled:NO];
return YES;
}
[self.button setEnabled:YES];
return YES;
}
Update: Sorry missed that bit about CodeData. In this case you should follow the instructions here, Disable/Enable NSButton if NSTextfield is empty or not,
The other way would be to give the controller a property exposing the
string value, bind the text field's value binding to this stringValue
property, and bind the button's enabled binding to the controller's
stringValue.length.
I have a view-based NSTableView. Each view in the table has a custom text field.
I'd like to fire an action when the user clicks on the text field (label) inside the table's view (imagine having a hyperlink with a custom action in each table cell).
I've created a basic NSTextField subclass to catch mouse events. However, they only fire on the second click, not the first click.
I tried using an NSButton and that fires right away.
Here's the code for the custom label:
#implementation HyperlinkTextField
- (void)mouseDown:(NSEvent *)theEvent {
NSLog(#"link mouse down");
}
- (void)mouseUp:(NSEvent *)theEvent {
NSLog(#"link mouse up");
}
- (BOOL)acceptsFirstResponder {
return YES;
}
- (BOOL)acceptsFirstMouse:(NSEvent *)theEvent {
return YES;
}
#end
Had the same problem. The accepted answer here didn't work for me. After much struggle, it magically worked when I selected "None" as against the default "Regular" with the other option being "Source List" for the "Highlight" option of the table view in IB!
Edit: The accepted answer turns out to be misleading as the method is to be overloaded for the table view and not for the text field as the answer suggests. It is given more clearly at https://stackoverflow.com/a/13579469/804616 but in any case, being more specific feels a bit hacky.
It turned out that NSTableView and NSOultineView handle the first responder status for NSTextField instances differently than for an NSButton.
The key to get the label to respond to the first click like a button is to overwrite [NSResponder validateProposedFirstResponder:forEvent:] to return YES in case of my custom text field class.
Documentation:
http://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Classes/NSResponder_Class/Reference/Reference.html#//apple_ref/occ/instm/NSResponder/validateProposedFirstResponder:forEvent:
The behavior that you're seeing is because the table view is the first responder, which it should be or the row won't change when you click on the label -- this is the behavior that a user expects when clicking on a table row. Instead of subclassing the label, I think it would be better to subclass the table view and override mouseDown: there. After calling the super's implementation of mouseDown:, you can do a hit test to check that the user clicked over the label.
#implementation CustomTable
- (void)mouseDown:(NSEvent *)theEvent
{
[super mouseDown:theEvent];
NSPoint point = [self convertPoint:theEvent.locationInWindow fromView:nil];
NSView *theView = [self hitTest:point];
if ([theView isKindOfClass:[NSTextField class]])
{
NSLog(#"%#",[(NSTextField *)theView stringValue]);
}
}
#end
In the exact same situation, embedding an NSButton with transparent set to true/YES worked for me.
class LinkButton: NSTextField {
var clickableButton:NSButton?
override func viewDidMoveToSuperview() {
let button = NSButton()
self.addSubview(button)
//setting constraints to cover the whole textfield area (I'm making use of SnapKit here, you should add the constraints your way or use frames
button.snp_makeConstraints { (make) -> Void in
make.edges.equalTo(NSEdgeInsetsZero)
}
button.target = self
button.action = Selector("pressed:")
button.transparent = true
}
func pressed(sender:AnyObject) {
print("pressed")
}
You use window.makeFirstResponser(myTextfield) to begin editing the text field. You send this message from the override mouseDown(withEvent TheEvent:NSEvent) method
This is my situation in Xcode Interface Builder:
There is also an NSArrayController in entity mode which controls the content of the NSTableView. I want to enable the 'Create' button when the NSTableView is empty (as controlled by the NSSearchField) AND when the text in the NSSearchField is not empty. How do I achieve that? Is it possible without programming?
To what KVO compliant values can I bind the 2 enabled conditions of the 'Create' button?
I don't think there's a way to do it entirely in interface builder, but with a small amount of code you can get it working pretty easily. First, make sure your controller (or App Delegate) is set as the delegate of the search field, and that it has IBOutlet connections to the search field, the button and the array controller. Here's how I would implement it:
// This is an arbitrary pointer to indicate which property has changed.
void *kObjectsChangedContext = &kObjectsChangedContext;
- (void)awakeFromNib {
// Register as an observer so we're notified when the objects change, and initially at startup.
[arrayController addObserver:self
forKeyPath:#"arrangedObjects"
options:NSKeyValueObservingOptionInitial
context:kObjectsChangedContext];
}
// This updates the button state (based on your specs)
- (void)updateButton {
BOOL canCreate = (searchField.stringValue.length > 0 &&
0 == [arrayController.arrangedObjects count]);
[createButton setEnabled:canCreate];
}
// This delegate method is called whenever the text changes; Update the button.
- (void)controlTextDidChange:(NSNotification *)obj {
[self updateButton];
}
// Here's where we get our KVO notifications; Update the button.
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
if (kObjectsChangedContext == context)
[self updateButton];
// It's good practice to pass on any notifications we're not registered for.
else {
[super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
}
}
If you're new to bindings some of that may look like Greek, hopefully the comments are clear enough.
I'm SOOO late for this, but came up with another method and just tested it in my app. It works, so I'm going to share it for anyone who will find this question in the future.
Basically what you want to do is to create a property WITHOUT a corresponding value in your controller
#property (readonly) BOOL enableProperty;
This means that there's actually no
BOOL enableProperty;
defined in the header file, or anywhere
then, rather than synthesize it, just write your own getter, and put there your condition
- (BOOL) enableProperty{
return (condition);
}
Third step: anytime there's the chance that your condition changes, notify it.
- (void) someMethod{
//.... Some code
[self willChangeValueForKey:#"enableProperty"];
[Thisline mightChange:theCondition];
[self didChangeValueForKey:#"enableProperty"];
//.... Some other code
}
fourth step: in IB, bind your control's enabled property to this "fake" property.
Enjoy! ;)
You seems to have a window, so presumably you have a controller object which is set as the File's Owner for the NIB file.
Why not declare a boolean property in this controller class, that returns a value based whatever conditions you want ?
#property(readonly) BOOL canCreate;
That you implement :
-(BOOL)canCreate {
// compute and return the value
}
Be sure to send KVO notifications appropriately when the conditions for the creation change.
The last step is to bind the button's enabled binding on the File's Owner canCreate key.
I have two NSTextFields: textFieldUserID and textFieldPassword.
For textFieldPassword, I have a delegate as follows:
- (void)controlTextDidEndEditing:(NSNotification *)aNotification
This delegate gets called when textFieldPassword has focus and I hit the enter key. This is exactly what I want.
My problem is that controlTextDidEndEditing also gets called when textFieldPassword has focus and I move the focus to textFieldUserID (via mouse or tab key). This is NOT what I want.
I tried using controlTextDidChange notification (which is getting called once per key press) but I was unable to figure out how to detect enter key ( [textFieldPassword stringValue] does not include the enter key). Can someone please help me figure this one out?
I also tried to detect if textFieldUserID was a firstResponder, but it did not work for me. Here is the code I tried out:
if ( [[[self window] firstResponder] isKindOfClass:[NSTextView class]] &&
[[self window] fieldEditor:NO forObject:nil] != nil ) {
NSTextField *field = [[[self window] firstResponder] delegate];
if (field == textFieldUserID) {
// do something based upon first-responder status
NSLog(#"is true");
}
}
I sure could use some help here!
If I understood you correctly, you could set an action for the password text field and tell the field to send its action only when the user types Return. Firstly, declare and implement an action in the class responsible for the behaviour when the user types Return on the password field. For example:
#interface SomeClass …
- (IBAction)returnOnPasswordField:(id)sender;
#end
#implementation SomeClass
- (IBAction)returnOnPasswordField:(id)sender {
// do something
}
#end
Making the text field send its action on Return only, and linking the action to a given IBAction and target, can be done either in Interface Builder or programatically.
In Interface Builder, use the Attributes Inspector, choose Action: Sent on Enter Only, and then link the text field action to an IBAction in the object that implements it, potentially the File’s Owner or the First Responder.
If you’d rather do it programatically, then:
// Make the text field send its action only when Return is pressed
[passwordTextFieldCell setSendsActionOnEndEditing:NO];
// The action selector according to the action defined in SomeClass
[passwordTextFieldCell setAction:#selector(returnOnPasswordField:)];
// someObject is the object that implements the action
[passwordTextFieldCell setTarget:someObject];
[passwordTextFieldCell setTarget:self];
[passwordTextFieldCell setAction:#selector(someAction:)];
- (void) someAction{
//handle
}
I have two NSTextFields: textFieldUserID and textFieldPassword.
For textFieldPassword, I have a delegate as follows:
- (void)controlTextDidEndEditing:(NSNotification *)aNotification
This delegate gets called when textFieldPassword has focus and I hit the enter key. This is exactly what I want.
My problem is that controlTextDidEndEditing also gets called when textFieldPassword has focus and I move the focus to textFieldUserID (via mouse or tab key). This is NOT what I want.
I tried using controlTextDidChange notification (which is getting called once per key press) but I was unable to figure out how to detect enter key ( [textFieldPassword stringValue] does not include the enter key). Can someone please help me figure this one out?
I also tried to detect if textFieldUserID was a firstResponder, but it did not work for me. Here is the code I tried out:
if ( [[[self window] firstResponder] isKindOfClass:[NSTextView class]] &&
[[self window] fieldEditor:NO forObject:nil] != nil ) {
NSTextField *field = [[[self window] firstResponder] delegate];
if (field == textFieldUserID) {
// do something based upon first-responder status
NSLog(#"is true");
}
}
I sure could use some help here!
If I understood you correctly, you could set an action for the password text field and tell the field to send its action only when the user types Return. Firstly, declare and implement an action in the class responsible for the behaviour when the user types Return on the password field. For example:
#interface SomeClass …
- (IBAction)returnOnPasswordField:(id)sender;
#end
#implementation SomeClass
- (IBAction)returnOnPasswordField:(id)sender {
// do something
}
#end
Making the text field send its action on Return only, and linking the action to a given IBAction and target, can be done either in Interface Builder or programatically.
In Interface Builder, use the Attributes Inspector, choose Action: Sent on Enter Only, and then link the text field action to an IBAction in the object that implements it, potentially the File’s Owner or the First Responder.
If you’d rather do it programatically, then:
// Make the text field send its action only when Return is pressed
[passwordTextFieldCell setSendsActionOnEndEditing:NO];
// The action selector according to the action defined in SomeClass
[passwordTextFieldCell setAction:#selector(returnOnPasswordField:)];
// someObject is the object that implements the action
[passwordTextFieldCell setTarget:someObject];
[passwordTextFieldCell setTarget:self];
[passwordTextFieldCell setAction:#selector(someAction:)];
- (void) someAction{
//handle
}