I want trigger the event if the text is changing in my NSTextView. Is there a way to trigger that directly from the NSTextView or I have to create a custom Class for the NSTextView?
- (void)textDidChange:(NSNotification *)notification
{
----do stuff here----
NSLog(#"text typed");
}
add the method to your code...enough
Related
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
I am brand spanking new to Cocoa programming, and am still kind of confused about how things wire together.
I need a pretty simple application that will fire off a single command (let's call it DoStuff) whenever any point on the window is clicked. After a bit of research it looks like subclassing NSView is the right way to go. My ClickerView.m file has this:
- (void)mouseDown:(NSEvent *)theEvent {
NSLog(#"mouse down");
}
And I have added the View to the Window and have it stretching across the whole thing, and is properly writing to the log every time the window is clicked.
I also have my doStuff method on my controller (this could be refactored to its own class I suppose, but for now it works):
- (IBAction)doStuff:(id)sender {
// do stuff here
}
So, how do I get mouseDown in ClickerView to be able to call DoStuff in the controller? I have a strong .NET background and with that, I'd just have a custom event in the ClickerView that the Controller would consume; I just don't know how to do that in Cocoa.
edit based on Joshua Nozzi's advice
I added an IBOutlet to my View (and changed it to subclass NSControl):
#interface ClickerView : NSControl {
IBOutlet BoothController *controller;
}
#end
I wired my controller to it by clicking and dragging from the controller item in the Outlets panel on the View to the controller. My mouseDown method now looks like:
- (void)mouseDown:(NSEvent *)theEvent {
NSLog(#"mouse down");
[controller start:self];
}
But the controller isn't instantiated, the debugger lists it as 0x0, and the message isn't sent.
You could either add it as an IBOutlet like Joshua said, or you could use the delegate pattern.
You would create a Protocol that describes your delegate's methods like
#protocol MyViewDelegate
- (void)doStuff:(NSEvent *)event;
#end
then you'd make your view controller conform to the MyViewDelegate protocol
#interface MyViewController: NSViewController <MyViewDelegate> {
// your other ivars etc would go here
}
#end
Then you need to provide the implementation of the doStuff: in the implementation of MyViewController:
- (void)doStuff:(NSEvent *)event
{
NSLog(#"Do stuff delegate was called");
}
then in your view you'd add a weak property for the delegate. The delegate should be weak, so that a retain loop doesn't form.
#interface MyView: NSView
#property (readwrite, weak) id<MyViewDelegate> delegate;
#end
and then in your view you'd have something like this
- (void)mouseDown:(NSEvent *)event
{
// Do whatever you need to do
// Check that the delegate has been set, and this it implements the doStuff: message
if (delegate && [delegate respondsToSelector:#selector(doStuff:)]) {
[delegate doStuff:event];
}
}
and finally :) whenever your view controller creates the view, you need to set the delegate
...
MyView *view = [viewController view];
[view setDelegate:viewController];
...
Now whenever your view is clicked, the delegate in your view controller should be called.
First, your view needs a reference to the controller. This can be a simple iVar set at runtime or an outlet (designated by IBOutlet) connected at design time.
Second, NSControl is a subclass of NSView, which provides the target/action mechanism machinery for free. Use that for target/action style controls. This provides a simple way of setting the reference to your controller (the target) and the method to call when fired (the action). Even if you don't use a cell, you can still use target/action easily (NSControl usually just forwards this stuff along to its instance of an NSCell subclass but doesn't have to).
you can also use a selector calling method,
define two properties in custom class:
#property id parent;
#property SEL selector;
set them in view controller:
graph.selector=#selector(onCalcRate:);
graph.parent=self;
and call as:
-(void)mouseDown:(NSEvent *)theEvent {
[super mouseDown:theEvent];
[_parent performSelector:_selector withObject:self];
}
I want to iterate thru all controls existing in a View on iOS when the view is loaded.
Also, it would be acceptable to have a callback that is called when these controls are initialized.
How can I obtain this?
To iterate through subviews (controls) in a parent view, call the parent view's -subviews method:
for (UIView *subview in [parentView subviews]) {
/* do something with subview */
}
You could subclass the control, creating a custom control. Here, you override the custom control view's initializer method. In this method, you would call the parent's initializer, and add your custom code.
for (UIView *aView in [myView subviews]) { //do something with aView }?
I have a NSTextView where i put the delegate to my file owner. My file owner is then assosiated with a class where i do different stuff in the view.
To my understanding it should now be possible to catch events from the NSTextView inside my class (because i have set its delegate to file owner), but it does not seem to work, why is that?
I have implemented this function in my class:
- (BOOL)control: (NSControl *)control textView:(NSTextView *)textView doCommandBySelector: (SEL)commandSelector {
NSLog(#"i was fired!");
return YES;
}
according to http://developer.apple.com/library/mac/#documentation/cocoa/Reference/NSTextViewDelegate_Protocol/Reference/Reference.html#//apple_ref/occ/intf/NSTextViewDelegate
the method signature looks like:
- (BOOL)textView:(NSTextView *)aTextView doCommandBySelector:(SEL)aSelector
give that a try instead.
The selector is just textView:doCommandBySelector:; drop the control.
I´m newbie with cocoa. I have a button and a textField in my app. I want the button disabled when the textfield is empty and enabled when the user type something.
Any point to start? Any "magic" binding in Interface Builder?
Thanks
[EDITED]
I´ve tried to set the appDelegate as the NSTextfield´s delegate and added this method (myTextfield and myButton are IBOutlets):
- (void)textDidChange:(NSNotification *)aNotification
{
if ([[myTextField stringValue]length]>0) {
[myButton setEnabled: YES];
}
else {
[myButton setEnabled: NO];
}
}
But nothing happens...
I´ve tried to set the appDelegate as the NSTextfield´s delegate and added this method (myTextfield and myButton are IBOutlets):
- (void)textDidChange:(NSNotification *)aNotification
{
if ([[myTextField stringValue]length]>0) {
[myButton setEnabled: YES];
}
else {
[myButton setEnabled: NO];
}
}
That's the hard way, but it should work just fine. Either you haven't hooked up the text field's delegate outlet to this object, you haven't hooked up the myTextField outlet to the text field, or you haven't hooked up the myButton outlet to the button.
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.
You could also give the controller two properties, one having a Boolean value, and set that one up as dependent upon the string property, and bind the button to that. That's a cleaner and possibly more robust solution, though it is more work.
Here's a solution using bindings.
Below I setup a NSTextField that is bound to the file owner's "text" property. "text" is a NSString. I was caught by "Continuously Updates Value". Thinking my solution didn't work but really it wasn't updating as the user typed, and only when the textfield lost focus.
And now setting up bindings on the button, simply set its enabled state to the length of the file owner's text property.
Annd, the working product.
If you use controlTextDidChange instead of textDidChange, you can get rid of the notification stuff and just rely on being the NSTextField's delegate.
Thanks Peter. What I missed (in my hard way version) is this piece of code in the awakeFromNib in the appDelegate:
NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
[center addObserver:self selector:#selector(textDidChange:) name:NSControlTextDidChangeNotification object:myTextField];
It works perfect. Now I´m trying the easy way, but I´m afraid I´m not still good enough with the bindings.
To bind the property
#property (retain) IBOutlet NSString *aStringValue;
with the textfield´s value, what I have to use in IB for "Bind to:", "Controller Key" and "Model Key Path"?