Hi
Is there a way to remove a view from another view of a specific class?
What I mean I have a view with multiple other views like a scrollview, imageview, tableview and I only want to remove the scrollview.
I thought the code would be something like this:
for (UIView *view in self.view.superview.subviews) {
if ([view.class == [Class UIScrollView]]]) {
[view removeFromSuperview];
}
}
But this didn't work. I could work with object at index: but because we don't know what index the scrollview has,so it also won't work. (I think)
Does someone knows the answer to this problem?
Thank you very much!
Is it this what you mean?
for (UIView *view in self.view.superview.subviews) {
if ([view isKindOfClass:[UIScrollView class]] ) {
NSLog(#"class");
}
}
If you can set an IBOutlet to the subview just call removeFromSuperview on the saved outlet.
(log the outlet to make sure it's set properly if that doesn't work)
(pretty sure that applies to both NSView and UIView)
Related
[self.scrollView scrollRectToVisible:textField.bounds animated:YES];
I can't seem to get my UIScrollView to scroll at all so that it doesn't obscure my UITextField. I thought that scrollRectToVisible would be my savior but it looks like a no go. Maybe I'm missing something like translating the coordinates of my textField to my scrollView. Either way check out my sample project.
https://github.com/stevemoser/Programming-iOS-Book-Examples/tree/master/ch20p573scrollViewAutoLayout2
Oh, and this project might be missing the delegate connection but I checked that and it still doesn't scroll.
I've seen other questions similar to this but none that mention Autolayout.
I was having issues with scrollRectToVisible:: as well after converting to Auto Layout. I just changed it to a direct call to setContentOffset:: and it started working again.
I had the same problem, I wanted to scroll an autolayouted UITextEdit into view without making it the first responder.
For me the issue was that the bounds of the UITextField were set later on during the auto layout pass, so if you do it immediately after setting up the layout the bounds are not valid yet.
To workaround I did create a descendant of UITextField, did overwrite setBounds: and added a 0 timer to scroll into view "later on" (You can't scroll in that moment because the auto layout pass of the system might no be finished at that point)
#interface MyTextField: UITextField
{
bool _scrollIntoView;
}
..
#end
#implementation MyTextField
-(void)setBounds:(CGRect)bounds
{
bool empty=CGRectIsEmpty(self.bounds);
bool isFirstResponder=self.isFirstResponder;
[super setBounds:bounds];
if (empty && !isFirstResponder && _scrollIntoView)
[self performSelector:#selector(scrollIntoViewLater) withObject:nil afterDelay:0];
else if (empty && isFirstResponder)
[self performSelector:#selector(becomeFirstResponder) withObject:nil afterDelay:0];
}
-(void)scrollIntoViewLater
{
CGRect r=[scrollView convertRect:self.bounds fromView:self];
[scrollView scrollRectToVisible:r animated:TRUE];
}
#end
If the field should be additionally editable with the on screen keyboard, simply call becomeFirstResponder later on: it scrolls automagically into view above the keyboard using the private scrollTextFieldToVisible API which in turn calls scrollRectToVisible:animated: of the scrollview.
Your sample link is broken btw...
I'm using an NSCollectionView to display various objects. The whole things works rather well, except for one annoying thing. I cannot figure out how to access the various controls on the view used to represent each object in the collection.
Here's the setup:
I have dragged an NSCollectionView into my view in IB.
I made a custom subclass of NSCollectionViewItem. Mapped my class in IB.
I made a custom subclass of NSBox to act as the view for each object in the collection. Also mapped this class in IB and connected it to the view property of my NSCollectionViewItem subclass.
I made all the bindings in IB to display the correct information for each object.
The view:
The resulting collection view:
Reasoning that that my subclass of NSCollectionViewItem is basically a controller for each view in the collection, I made referencing outlets of the various controls in the view in my controller subclass:
#interface SourceCollectionViewItem : NSCollectionViewItem
#property (weak) IBOutlet NSTextField *nameTextField;
#property (weak) IBOutlet NSTextField *typeTextField;
#property (weak) IBOutlet RSLabelView *labelView;
#property (weak) IBOutlet NSButton *viewButton;
#end
When I inspect any instance of SourceCollectionViewItem in the debugger, all the properties show up as nil despite the fact that I can actually see them on my screen and that everything is displayed as it should be.
My setup was inspired by Apple's sample app IconCollection.
I am obviously missing something. What?
EDIT: I found various posts hinting at a similar issue:
CocoaBuilder.com and this question on SO.
EDIT: Just to be complete: this post deals with the subject as well and delivers a solution based on a combination of the options mentioned in the accepted answer.
Outlets are set during nib loading, and only the prototype item is loaded from nib and has its outlets assigned. All other ViewItems and their Views are cloned from the prototype, in that case outlets are just instance variables that are never initialized.
Here are the options I could come up with:
Override newItemForRepresentedObject: of collection view and reload nib instead of cloning the prototype. But this will probably hurt the performance greatly.
Override copyWithZone of collection view item and assign outlets manually using viewWithTag: to find them.
Give up and try to provide data via bindings only.
I found that overriding NSCollectionViewItem's -setRepresentedObject: could also be a good choice, as it is called on the new Item when all IBOutlet seem to be ready. After the call to super you can do whatever is needed:
- (void)setRepresentedObject:(id)representedObject
{
if (representedObject) {
[super setRepresentedObject:representedObject];
[self.anOutlet bind:#"property" toObject:self.representedObject withKeyPath:#"representeProperty" options:nil];
}
}
I used this method to bind a custom property of an interface object. The check is there to avoid useless calls, when the representedObject is not yet ready. The project uses a separate xib for the ViewItem, as explained in the links in the original edits.
Great question. Like #hamstergene suggests, you can use copyWithZone, it will be much more efficient compared to newItemForRepresentedObject. However viewWithTag is not always an option, first, because not everything can be tagged (easily), and, second, using tag for this purpose is a little wrong. Here's a cool approach with performance in mind, in Swift.
import AppKit
class MyViewController: NSCollectionItemView
{
// Here you are cloning the original item loaded from the storyboard, which has
// outlets available, but as you've seen the default implementation doesn't take
// care of them. Each view has a unique identifiers, which you can use to find it
// in sublayers. What's really cool about this, is that you don't need to assign
// any tags or do anything else while having advantage of better performance using
// cached nib object.
override func copyWithZone(zone: NSZone) -> AnyObject {
let copy: NSCollectionItemView = super.copyWithZone(zone) as! NSCollectionItemView
let oldView: RecordingView = self.view as! MyView
let newView: RecordingView = copy.view as! MyView
newView.foo = newView.viewWithIdentifier(oldView.foo.identifier!) as! NSTextfield
newView.bar = newView.viewWithIdentifier(oldView.bar.identifier!) as! NSImageView
return copy
}
}
#IBDesignable class MyView: View
{
// Custom collection view item view. Lets assume inside of it you have two subviews which you want
// to access in your code.
#IBOutlet weak var foo: NSTextfield!
#IBOutlet weak var bar: NSImageView!
}
extension NSView
{
// Similar to viewWithTag, finds views with the given identifier.
func viewWithIdentifier(identifier: String) -> NSView? {
for subview in self.subviews {
if subview.identifier == identifier {
return subview
} else if subview.subviews.count > 0, let subview: NSView = subview.viewWithIdentifier(identifier) {
return subview
}
}
return nil
}
}
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 have this code to load an NSView from a NIB and add it to another NSView:
// INIT
- (void)awakeFromNib {
// Load nib
DNListViewController *listViewController = [[DNListViewController alloc] initWithNibName:#"ListView" bundle:nil];
// Add view to window
[listViewController.view setFrame:detailView.frame];
[detailView addSubview:listViewController.view];
// MEM
[listViewController release];
}
All outlets are connected right, but nothing shows up. I don't understand why! Can someone help me? Thanks.
This is about NSViews, not UIViews!
Oh, I fixed it already. Nevermind, I'll let is stay here for people from the future.
[listViewController.view setFrame:detailView.frame];
must be
[listViewController.view setFrame:detailView.bounds];
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"?