In simple words, $(document).ready is an event which fires up when document is ready. Suppose you have placed your jQuery code in head section and trying to access a dom element (an anchor, an img etc), you will not be able to access it because html is interpreted from top to bottom and your html … Read more
Yep, a Swing Timer and Key Bindings would work well. Here’s another example (mine) 🙂 import java.awt.*; import java.awt.event.*; import java.awt.image.BufferedImage; import javax.swing.*; public class AnimationWithKeyBinding { private static void createAndShowUI() { AnimationPanel panel = new AnimationPanel(); // the drawing JPanel JFrame frame = new JFrame(“Animation With Key Binding”); frame.getContentPane().add(panel); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } … Read more
The cause is simple to explain: while an event handler is subscribed, the publisher of the event holds a reference to the subscriber via the event handler delegate (assuming the delegate is an instance method). If the publisher lives longer than the subscriber, then it will keep the subscriber alive even when there are no … Read more
From proper way to do uitextfield text change call back: I catch the characters sent to a UITextField control something like this: // Add a “textFieldDidChange” notification method to the text field control. In Objective-C: [textField addTarget:self action:@selector(textFieldDidChange:) forControlEvents:UIControlEventEditingChanged]; In Swift: textField.addTarget(self, action: #selector(textFieldDidChange), for: .editingChanged) Then in the textFieldDidChange method you can examine the … Read more
See How to find event listeners on a DOM node. In a nutshell, assuming at some point an event handler is attached to your element (eg): $(‘#foo’).click(function() { console.log(‘clicked!’) }); You inspect it like so: jQuery 1.3.x var clickEvents = $(‘#foo’).data(“events”).click; jQuery.each(clickEvents, function(key, value) { console.log(value) // prints “function() { console.log(‘clicked!’) }” }) jQuery 1.4.x … Read more
When you draw to a canvas element, you are simply drawing a bitmap in immediate mode. The elements (shapes, lines, images) that are drawn have no representation besides the pixels they use and their colour. Therefore, to get a click event on a canvas element (shape), you need to capture click events on the canvas … Read more
e.target is what triggers the event dispatcher to trigger and e.currentTarget is what you assigned your listener to.
For the specific question “Will pClass be garbage collected”: the event subscription has no effect on the collection of pClass (as the publisher). For GC in general (in particular, the target): it depends whether MyFunction is static or instance-based. A delegate (such as an event subscription) to an instance method includes a reference to the … Read more
The problem is autofill is handled differently by different browsers. Some dispatch the change event, some don’t. So it is almost impossible to hook onto an event which is triggered when browser autocompletes an input field. Change event trigger for different browsers: For username/password fields: Firefox 4, IE 7, and IE 8 don’t dispatch the … Read more
To understand event handlers, you need to understand delegates. In C#, you can think of a delegate as a pointer (or a reference) to a method. This is useful because the pointer can be passed around as a value. The central concept of a delegate is its signature, or shape. That is (1) the return … Read more