observer-pattern

In my app I want to update the Navigation Drawer with the username's nickname and email after he's logged in. From my MainActivity I am starting a LoginActivity with the startActivityForResult(intent, PICK_ACCOUNT_REQUEST); method to get the users registered or logged in. After the LoginActivity returns the Intent data result (his NAME and EMAIL ) back to MainActivity , the method onActivityResult() is called and there I try to update the class' global variables NAME and EMAIL with the newly received data, with no success: after every registration or log the two fields never show in the

In my application I have many classes. Most of these classes store quite some data, and it is important that other modules in my application are also 'updated' if the content of one of the data classes changes. The typical way to do this is like this: void MyDataClass::setMember(double d) { m_member = d; notifyAllObservers(); } This is a quite good method if the member is not often changed and the 'observing classes' need to be up-to-date as fast as possible. Another way of observing the changes is this: void MyDataClass::setMember(double d) { setDirty(); m_member = d; } This is a good method

I have an issue with Observable in Angular 2. I subscribe my component to an observable, then when my service has new value, my component is notified. Problem is when the observer push an error, like an HTTP error, my observable is closed, so my component is no more notified. Question How can I do to make my component continue listening my service even when I have an error ? Example Here an example Here my code : Component constructor(private appService: AppService) { //I subscribe my component to an observable this.appService.commentsObservable.subscribe((comments) => { console.log(comments);

I'm experiencing a strange problem with Knockout's mapping plug-in. If I fill an observable array through mapping I can't iterate the array or get its length, even though the UI is updated correctly, the array seems empty. You can find a working jsFiddle here: http://jsfiddle.net/VsbsC/ This is the HTML mark-up: <p><input data-bind="click: load" type="button" value="Load" /></p> <p><input data-bind="click: check" type="button" value="Check" /></p> <table> <tbody data-bind="foreach: items"> <tr> <td data-bind="text: name"></td> <td data-bind="text: value"></td> </tr> </tbody> </table> <p data

I have a class let's say MyJFrame which represent the GUI of my application. It implements the interface Observer and override the method update . public class MyJFrame extends JFrame implements Observer{ ... public void update(Observable arg0, Object arg1){ ... } } Now I want to make also my JFram an Observable object but I can't because it already extend the class JFrame . I tried to create a variable of type Observable in my class. public class MyJFrame extends JFrame implements Observer{ Observable observable = new Observable(); The problem here is that I can add Observer to this

I need to track tableView.contentOffset.y Is it possible to add observer to tableView.contentOffset? I think this is impossible because contentOffset doesn't inherit NSObject class. Is any other solution? UITableView is a UIScrollView subclass so you can use the UIScrollViewDelegate method scrollViewDidScroll: to be notified when the view scrolled. Check the contentOffset of the scrollView in that method contentOffset is a key path, so you can also observe its changes using KVO [self.tableView addObserver:self forKeyPath:@"contentOffset" options:NSKeyValueObservingOptionNew |

In android i use Timer to execute task that repeats every 5 seconds and starts after 1 second in this way: Timer timer = new Timer(); timer.scheduleAtFixedRate(new TimerTask() { @Override public void run() { // Here is the repeated task } }, /*Start after*/1000, /*Repeats every*/5000); // here i stop the timer timer.cancel(); this timer will repeat Until i call timer.cancel() I am learning RxJava with RxAndroid extension So i found this code on internet, i tried it and it doesnt repeat: Observable.timer(3000, TimeUnit.MILLISECONDS) .subscribeOn(Schedulers.newThread()) .observeOn