I have an NSImageView subclass that I use for dragging and dropping Files onto in my app.
To do this I created a subclass of NSImageView and also dragged the NSImageView onto my XIB, I then set the class of the XIB NSImageView Object to my custom subclass.
Everything works well with the drag and drop and I know I have the correct file after the drag.
The problem comes in when I want to update a textfield on the MainViewController based on the file dragged in.
I created the following subclass and protocol
#import <Cocoa/Cocoa.h>
#import <Quartz/Quartz.h>
#protocol PDFDraggedIntoWell <NSObject>
#required
-(void)PDFDraggedIntoWellWithURL:(NSURL*) importedURL;
#end
#interface DragAndDropImageView : NSImageView
#property (strong) id <PDFDraggedIntoWell> delegate;
#end
Then in my implementation in the subclass I try to call the delegate method
-(void) finishedDragginInFileWithURL:(NSURL*) importedURL{
if( self.delegate != nil && [ self.delegate respondsToSelector: #selector(PDFDraggedIntoWellWithURL:)]) {
[self.delegate performSelector:#selector(PDFDraggedIntoWellWithURL:) withObject:importedURL];
}
}
The problem I run into is how do you assign the delegate. From the XIB NSImageView to my MainviewController I connect up an IBOutlet
#property (weak) IBOutlet DragAndDropImageView *draggedFileImageView;
And I have declared that my ViewController will receive the delegate
#interface MyMainUIViewController ()<PDFDraggedIntoWell>
with the appropriate method implemented
-(void) PDFDraggedIntoWellWithURL:(NSURL *)importedURL{ }
Now I have tried in various places to assign delegate to self (in viewDidLoad - which doesn’t get called since the view is being loaded in a XIB??) and also in
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
but all I get back is the delegate is still nil when debugging.
What am I doing wrong? Thanks for the help!!
If you are using xibx the initWithCoder method is called for initialization. Set your delegate there.
- (id)initWithCoder:(NSCoder *)aDecoder {
self = [super initWithCoder:aDecoder];
if (self) {
UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 10, 10)];
myView.delegate = self;
}
return self;
}
Alternatively set the delegate via interface builder by dragging wile holding ctrl from the File's Owner to your view. Like this:
I was able to add add the delegate to the awakefromnib(in mymainviewcontroller) method and things are working fine now. Thanks
Related
I'm showing an NSPopover in an NSView, originating from a point on an NSBezierPath. I'm able to show the popover without a problem, but I can't seem to set the string value of the two text fields in it. The popover and the content view are both a custom subclass of NSPopover and NSViewController, respectively. The NSPopover subclass is also the NSPopover's delegate, although I don't implement any delegate methods, so I'm not sure I even need to do that.
Here is my subclass of NSViewController:
#import <Cocoa/Cocoa.h>
#interface WeightPopoverViewController : NSViewController
#end
#import "WeightPopoverViewController.h"
#interface WeightPopoverViewController ()
#end
#implementation WeightPopoverViewController
- (id)init {
self = [super initWithNibName:#"WeightPopoverViewController" bundle:nil];
if (self) {
}
return self;
}
#end
And my subclass of NSPopover:
#import <Cocoa/Cocoa.h>
#interface WeightPopoverController : NSPopover <NSPopoverDelegate> {
NSTextField *dateLabel;
NSTextField *weightLabel;
}
#property (strong) IBOutlet NSTextField *dateLabel;
#property (strong) IBOutlet NSTextField *weightLabel;
#end
#import "WeightPopoverController.h"
#implementation WeightPopoverController
#synthesize weightLabel;
#synthesize dateLabel;
#end
This is the code in my NSView subclass that opens up the popover:
#interface WeightGraphViewController () {
WeightPopoverController *popover;
WeightPopoverViewController *vc;
}
...
-(void)mouseEntered:(NSEvent *)theEvent {
// initialize the popover and its view controller
vc = [[WeightPopoverViewController alloc] init];
popover = [[WeightPopoverController alloc] init];
// configure popover
[popover setContentViewController:vc];
[popover setDelegate:popover];
[popover setAnimates:NO];
// set labels
for (id key in (id)[theEvent userData]) {
[popover.weightLabel setStringValue:[(NSDictionary*)[theEvent userData] objectForKey:key]];
[popover.dateLabel setStringValue:key];
}
// set the location
(redacted, irrelevant)
// show popover
[popover showRelativeToRect:rect ofView:[self window].contentView preferredEdge:NSMaxYEdge];
}
-(void)mouseExited:(NSEvent *)theEvent {
[popover close];
popover = nil;
}
In WeightPopoverViewController.xib, I've set the File's Owner to WeightPopoverViewController and connected the view to the custom NSView. In this xib I also have an Object set to WeightPopoverController with the dateLabel and weightLabel connected to their text fields and the contentViewController set to File's Owner.
I think where I am going wrong is likely related to how I have configured my class / instance variables for the NSPopover, but from the research I've done and documentation I've read I can't seem to crack where I've gone wrong. Any help would be appreciated.
UPDATE:
I removed the NSPopover subclass from code and from IB. I put my outlets in my NSViewController and connected them in IB. However, I'm still not able to set the string values. The following won't compile with the error "Property 'weightLabel' not found on object of type NSPopover*'".
#interface WeightGraphViewController () {
NSPopover *popover;
...
}
-(void)mouseEntered:(NSEvent *)theEvent {
vc = [[WeightPopoverViewController alloc] init];
popover = [[NSPopover alloc] init];
[popover setContentViewController:vc];
[popover.dateLabel setStringValue:#"test"];
}
I have the property definition exactly as I had it in my NSPopover subclass, but now in my NSViewController. This is actually what I had before, and since I wasn't able to set the properties from the NSViewController, I figured I needed to do it through a subclass of NSPopover. This is why I thought I am having an issue with how I have configured my class / instance variables.
You seem to be creating two popovers, one in code (popover = [[WeightPopoverController alloc] init]) and one in Interface Builder (In this xib I also have an Object set to WeightPopoverController). Have a think about what you’re trying to achieve.
I would also advise against subclassing NSPopover. I believe this is causing confusion and is unnecessary. Instead, put the outlets to your dateLabel and weightLabel in the popover’s content view controller.
I've experienced something that I think is similar. The root problem is that the "outlets" connecting your view (XIB) to your controller are not initialized until after the view has been displayed. If the controller tries to set properties on any UI controls in the view before the popover has been opened, those changes are ignored (since all the controls will be nil).
Luckily, there's an easy solution (as mentioned in this answer): just invoke the view getter on your controller, and it will force the view to initialize sooner.
In other words:
popover = [NSPopover new];
myController = [[MyViewController alloc] initWithNibName:#"MyView" bundle:nil];
popover.contentViewController = myController;
[myController view]; // force view to initialize
...set some values on myController... // works because view is now loaded
[popover showRelativeToRect: ...];
I am working on a front end for a project in objective-c and I am having some trouble getting methods of my class Window which is a subclass of NSViewController to fully execute when called from a different class.
I have a method of the class Window that is called setColor which changes the color of my NSTableView variable which is linked to a bordered scroll view in my interface. I am able to successfully change the color by calling the setColor method like this from the init method in Window: [self setColor :self];
However when I do this [window1 setColor: window1] with window1 being an object of the class Window that I have declared in class Door, nothing seems to happen since the color of the boarded scroll view remains the same.
My Window.h file looks like this:
#interface Window : NSViewController {
#public
IBOutlet NSTableView *dataTableView;
}
#property (retain) IBOutlet NSTableView *tableView;
- (IBAction)SetColor:(id)sender;
#end
My Window.m looks like this:
#synthesize tableView;
- (void) awakeFromNib {
// [self SetColor :self];
}
- (IBAction)SetColor:(id)sender;
{
NSLog(#"changing the color");
[self->tableView setBackgroundColor: NSColor.blueColor];
}
Door.h looks like this
#interface Door : NSViewController {
Window* window1;
}
-(IBAction)buttonPress:(id)sender;
#property (retain) Window* window1;
#end
Door.m looks like this:
-(void) dealloc{
[window1 release];
}
-(id)init{
self = [super init];
if(self){
window1 = [Window alloc];
}
-(IBAction)buttonPress :(id)Sender;
{
[window1 setColor: window1];
}
I am using Xcode 3.2 so I cannot use ARC.
window1 = [Window alloc] will not load a Nib or storyboard and connect the outlet IBOutlet NSTableView *dataTableView to the table view inside it.
If "Window" is a view controller, you need to initialize it and the outlets in it a more standard way. View controllers need the proper initialization or the outlets are nil, and in Objective-C, if you send a method to nil, it just does nothing.
CONFIGURATION:
-UIviewController embedded in Navigationcontroller.
-UIviewController has a UIscrollview as subview
-UIscrollview has some views where charts are created: each view containing a chart has its own .h and .m file and from this file I want trigger a segue to a tableview controller.
-A Tableviewcontroller was added in xcode and a segue from the UIviewController to the TableViewcontroller was created as well (Xcode)
-created a protocol in the UIView to have the segue pushed from there.
PROBLEM:
delegate always nil, segue method will never be called
UIVIEW .h file
#protocol UItoUIvcDelegate <NSObject>
-(void)triggerSegue;
#end
#interface CFfirstGraph : UIView <CPTPlotDataSource , CPTPieChartDelegate,UIActionSheetDelegate>
#property(weak, nonatomic) id <UItoUIvcDelegate> delegate;
#end
UIVIEW .m file (snippet)
-(void)pieChart:(CPTPieChart *)pieChart sliceWasSelectedAtRecordIndex:(NSUInteger)index
{
if (self.delegate == nil)
{
NSLog(#"nil");
}
[self.delegate triggerSegue];
}
UIVIEWCONTROLLER .h file
#import "CFfirstGraph.h"
#interface CFMainViewController : UIViewController <UItoUIvcDelegate, UITableViewDelegate, UITableViewDataSource>
#end
UIVIEWCONTROLLER .m file (snippet)
- (void)viewDidLoad
{
[super viewDidLoad];
self.scrollView.contentSize = CGSizeMake(320, 1000);
[self.view addSubview:self.scrollView];
CFfirstGraph *click =[[CFfirstGraph alloc]init];
click.delegate = self ;
}
-(void)triggerSegue
{
[self performSegueWithIdentifier:#"detailedData" sender:self];
NSLog(#"estoy aqui");
}
What am I doing wrong ? why the delegate is always nil ? I tried to add the method setDelegate but still no luck.
Thanks,
dom
Make CFfirstGraph as a strong property.
#property (strong, nonatomic) CFfirstGraph * click;
- (void)viewDidLoad
{
[super viewDidLoad];
self.click =[[CFfirstGraph alloc]init];
self.click.delegate = self ;
self.scrollView.contentSize = CGSizeMake(320, 1000);
[self.view addSubview:self.scrollView];
}
ok, after many hours of sweat I found the issue.
First...delegate = nil was not the main problem.
The real issue was the protocol method triggering the segue was never called.
If i create and initialize a CFfirstGraph object (or even property) it won't be related to the view created already in x-code, and this is the main issue.
On the other hand...if I "CTRL-drag" an outlet from the UIview to the CFMainViewController i will have a property that is exactly the one i need:
#interface CFMainViewController () <UIScrollViewDelegate>
#property (weak, nonatomic) IBOutlet CFfirstGraph *FirstGraph;
Then i assign the delegate to self (CFMainViewController) in the viewDidLoad:
- (void)viewDidLoad
{
[super viewDidLoad];
self.FirstGraph.delegate = self ;
}
and the delegate method "triggerSegue" will be executed being called from the UIVIEW.
Best Regards,
dom
I have a Subclass of NSObject in which I want to call IMMEDIATELY (a sort of -(void)viewDidLoad) a method (in this case to load a MkMapView): what's the better way to do this? I think I cant use viewDidLoad, so can I use performSelector?
SubClass.h
#interface Mysubclass : NSObject <MKMapViewDelegate> {
}
SubClass.m (1st alternative)
-(id)init{
self = [super init];
if ( self != nil ) {
// THE CODE TO INITIALIZE MKMAPVIEW
}
return self
}
OR
SubClass.m (2nd alternative)
-(id)init{
[self performSelector:#selector(myMethod)];
return self;
}
-myMethod{
// THE CODE TO INITIALIZE MKMAPVIEW
}
What's the better (or correct) alternative? Its possible to avoid -(id)init? Or everytime I add a subclass, to call a method I have to write it into -(id)init? Thank you!
There is no reason to use -performSelector: in this context. If you want to add a method that initializes the MKMapView when your object is created, call the method from within the if (self) block:
- (id)init
{
self = [super init];
if (self) {
[self setupMapView];
}
return self;
}
- (void)setupMapView
{
// THE CODE TO INITIALIZE MKMAPVIEW
}
It is a matter of personal preference/style whether to have a second method -setupMapView or to simply leave the code for setting up the MKMapView in the if (self) block of the -init method or to break the code off into a second method -setupMapView called from -init.
That being said, it sounds like other things may be off with your setup. Your MKMapView should [most likely] be within a UIViewController subclass (which will probably have an associated XIB), so you will be have access to -viewDidLoad. Note that your UIViewController subclass will serve as the delegate to your MKMapView.
Update 1
In your UIViewController subclass instance (I'll assume you called it ViewController, you should have an IBOutlet to an MKMapView object. Do this in ViewController.h either by (1) adding an instance variable
#interface ViewController : UIViewController
{
IBOutlet MKMapView *myMap;
}
#end
or by (2) adding a property
#interface ViewController : UIViewController
#property (nonatomic, strong, readwrite) IBOutlet MKMapView *myMap;
#end
Now open ViewController.xib in Interface Builder. You should have an MKMapView inside the view. If you don't already, add one from the Object Library. Right click on File's Owner. Locate the row with the item myMap. Drag from the circle on the right end of the row to the MKMapView in the visible view.
Your ViewController class now has an outlet to the MKMapView. You will be able to send messages to the MKMapView subview of your view controllers view after it has been loaded.
You should have a property or an instance variable for your SubClass instance so that it doesn't get destroyed as soon as -viewDidLoad returns. Do this again by either adding an instance variable to ViewController.h
#interface ViewController : UIViewController
{
IBOutlet MKMapView *myMap;
SubClass *istance;
}
#end
or by adding a property
#interface ViewController : UIViewController
#property (nonatomic, strong, readwrite) IBOutlet MKMapView *myMap;
#property (nonatomic, strong, readwrite) SubClass *istance;
#end
Now, in ViewController.m, you need to define -viewDidLoad so that self.istance is set as the delegate of self.myMap. In the comments, I had suggested creating your own initializer -initWithMapView:. If you plan on having SubClass do some extensive set-up of your MKMapView, that makes sense. If you just want SubClass to be the delegate of the MKMapView, there's no need for such a method.
Let's consider both cases:
(1) using a method -[SubClass initWithMapView:]:
In ViewController.m you'll have (within the #implementation of ViewController)
- (void)viewDidLoad
{
self.istance = [[SubClass alloc] initWithMapView:self.myMap];
}
In SubClass.h you'll have (within the #interface of SubClass)
- (id)initWithMapView:(MKMapView *)mapView;
#property (nonatomic, weak, readwrite) MKMapView *mapView;
In SubClass.m you'll have (within the #implementation of SubClass)
- (id)initWithMapView:(MKMapView *)mapView
{
self = [super init];
if (self) {
self.mapView = mapView;
self.mapView.delegate = self;
//more setup of mapView.
}
return self;
}
(2) using -[SubClass init]:
Instead, in ViewController.m you'll have
- (void)viewDidLoad
{
self.istance = [[SubClass alloc] init];
self.myMap.delegate = self.istance;
}
I've only programmed on the iPhone so far, so Cocoa is sort of confusing in certain ways for me. Here's where I've hit a snag. I wanted my window so that the background was invisible, and without a title-bar. Something like this:
Here's how I'm doing it:
I set my window's class to a custom window, which I've created like this:
CustomWindow.h
#import <Foundation/Foundation.h>
#import <Cocoa/Cocoa.h>
#interface CustomWindow : NSWindow {
#private
NSPoint initialLocation;
}
#property(assign)NSPoint initialLocation;
#end
CustomWindow.m
//trimmed to show important part
#import "CustomWindow.h"
#implementation CustomWindow
#synthesize initialLocation;
- (id)initWithContentRect:(NSRect)contentRect styleMask:(NSUInteger)aStyle backing:(NSBackingStoreType)bufferingType defer:(BOOL)flag {
// Removes the window title bar
self = [super initWithContentRect:contentRect styleMask:NSBorderlessWindowMask backing:NSBackingStoreBuffered defer:NO];
if (self != nil) {
[self setAlphaValue:1.0];
[self setOpaque:NO];
}
return self;
}
#end
Now, in my .xib file for this window I've added a custom view onto the window. I've set the view class to a custom class I've created that inherits from NSView. Here's how I'm setting that up:
MainView.h
#import <Cocoa/Cocoa.h>
#interface MainView : NSView {
#private
//nothing to see here, add later
}
#end
MainView.m
//trimmed greatly again to show important part
#import "MainView.h"
#implementation MainView
- (id)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self) {
}
return self;
}
- (void)drawRect:(NSRect)rect {
// Clear the drawing rect.
[[NSColor clearColor] set];
NSRectFill([self frame]);
}
#end
So here's my question. I've added a NSImageView to my custom view (MainView) in Interface Builder. However, for some reason I can't figure out how to connect this image view to an instance variable in my custom view. They seem like they can't be connected like I normally would if I was creating an iPhone app. Any ideas how this would be done?
You connect objects created in your XIB in Mac OS X the same way you do for iOS programs. Just add an NSImageView property to your main view, mark it as an IBOutlet and connect it up.
For example,
In MainView.h create a property for your NSImageView and make it an IBOutlet:
#import <Cocoa/Cocoa.h>
#interface MainView : NSView {
NSImageView *imageView;
}
#property(retain) IBOutlet NSImageView *imageView;
#end
In interface builder, make sure the class for the custom view is set to MainView, to do this click on the File's Owner object in the custom view XIB and then select the identity option in the inspector and enter MainView as the class type.
Next, CTRL+click File's owner and drag the arrow to the NSImageView and select the imageView outlet.
That's all there is to it. You should be able to reference the image view from code now.