Swing/AWT/SWT :: Why Should GUI Code Be Placed On EDT
Oct 3, 2014
According to what I read, “when programming in Swing, your GUI creation code should be placed on the Event Dispatch Thread (EDT). This will prevent potential race conditions that could lead to deadlock.” (See below for code.)
Why is this? How could making a GUI lead to deadlock?
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
According to what I read, "when programming in Swing, your GUI creation code should be placed on the Event Dispatch Thread (EDT). This will prevent potential race conditions that could lead to deadlock." (See below for code.)
Why is this? How could making a GUI lead to deadlock?
public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); }
How do I get my GUI code into a GUI format? I wrote this put it will not make a GUI image.
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package Ofelia_Inventory_4; import java.awt.*; import java.awt.event.*;
is any simple way to apply the same code on both ActionListener and MouseListener, so that the same code is executed when the user either presses a JButton or presses Enter when a JTextField is focused.I know that I can define a method, while it is not preferred as I may use break; in my MouseListener.
A simple example:
import java.awt.*; import java.awt.event.*; import javax.swing.*; public class TwoListener extends JFrame {
[code]....
Although I can define a new method that prints out the three numbers, I have to add certain break; code in different cases. So I just wonder whether there is another way to do things like this.
if the above code is to launch another application using java then how can I close/exit the same(another) application using java code once I press the exit button of my java app.
I am trying to make a JTree. I have used this guide :[URL]
Now when I call my Class with
TreeMainMenu tree = new TreeMainMenu(); JScrollPane MainMenu = new JScrollPane(tree);
I get only the default JTree..
I need to understand how I should build my code to call the class as JTree.
This is my code:
public class TreeMainMenu extends JTree { private DefaultMutableTreeNode top = new DefaultMutableTreeNode("TOP"); JTree tree; public JTree TreeMainMenu() { APNode(); tree = new JTree(top); tree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION); return tree;
I am messing around with a Swing application and am a bit stuck as to how to join the front and back ends.This is the code for the DataManager class which is responsible for loading and saving objects and interfacing with rest of the system. The data I need displayed comes from a .txt file in the applications directory. I need to show certain aspects of the data in the JComboBoxes in the GUI class.
Java Code:
package programdataapplication; import java.io.*; import java.util.*; public class DataManager {
I have a program where I have to open a file and then run a piece of code to do something with it. However since there are different files I want to run different pieces of code depending on the file. I have a JFileChooser setup and it works but I would like to have a something like an if else depending on the file extension.
How to deploy Java Swing application as windows software. I have tried the following to do this :
I have created jar file for my project after that created exe file using Launch4j and Advanced installer, exe file produced by both software are working fine but those are placing the jar file inside that exe file, My problem is any one who has that exe file can extract and view the source code by decompiling java class file. Is there any way to deploy java application without decompiling the code.
i've spend an hour or two, pasting fragments from tutorials and nothing changed.
Well - i have GUI, that have JComboBox with two elements: String[] fedoras = { "Fedora 19", "Fedora 20" }; JComboBox fedora_list = new JComboBox(fedoras); fedora_list.setSelectedIndex(0); fedora_list.setBounds(120,170, 170,25); fedora_list.addActionListener(this); this.add(fedora_list);
Below i have normal button (named Update) with "update" set as ActionCommand. This button after clicked should check which value from list is selected and perform different operations for that elements. But it's harder than i thought.
Code for update button:
public void actionPerformed(ActionEvent e){ String cmd = e.getActionCommand(); (...) else if ("update".equals(cmd)){ String selectedFedora = (String) fedora_list.getSelectedItem(); if (selectedFedora.equals("Fedora 19")) {
[code]....
- after user clicked Update button, button should check which value is selected in JComboBox (fedora_list). - if Fedora 19 is selected and button clicked, then action in Xterm - if Fedora 20 is selected, this same action in Xterm is performed, but for Fedora Linux 20
The problem is - i don't know hot to code Update button to check which value from fedora_list (JComboBox) is selected and perform other actions for every element on List.
When editing a cell, the existing code would use the right/left cursor keys to move from cell to cell as opposed to from character to character when editing a cell. I planned to override the functionality by tossing in the above code as a test to see if it stops the functionality before I override it.
After placing in the above code, the above functionality no longer occurs, but now the cursor moves within the cell as I wanted which is to move from character to character instead of cell to cell. Its great it works, but it really shouldn't. Essentially the default behavior has been restored when it should have really disabled the left/right keys.
I assume there is some underlying class someplace that is doing something to affect the behavior. Since a sample can't be provided I am wondering in what scenarios would the e.consume() restore default functionality?
I was a bit confused of the code generated by the Axis2 Code Gen.
I have created a logIn(String username, String password) method in my service and used Axis2 Code Gen to generate the Stub.
I try to access the logIn method from my Client using the Stub like below:
TestServiceStub stub = new TestServiceStub("http://localhost:8080/axis2/services/TestService"); String test = stub.logIn("user","pass").
but instead of UserName and password as the parameters, the Stub created a Login object as the parameter for the logIn method. like the one below:
stub.logIn(Login login1);
I wanted to try the logIn method by providing a static userName and password but it seems impossible because the Stub changed the parameter for the logIn method.
The code here I have works fine if I just want to ask the user to enter four digits: //java application that asks user to input binary numbers(1 or 0) and convert them to decimal numbers import java.util.Scanner; //program uses class scanner public class binarynumber{
//main method that executes the java application public static void main(String args[]){ //declares variables
int digit; int base=2; int degree; double decimal; int binary_zero=0; int binary_one=1; //create scanner for object input
[code]....
The thing is, I want the java application to input more than four digits for the user and I want it to loop it manytimes f until the user ask it to stop.
I need to create a Java program that takes an input a color code in HSV and outputs the equivalent RGB code and Vice versa.
Example: If you test on the color RED in RGB: Input: (255,0,0) Output: (0,100%,100%) If you test on the color RED in HSV: Input0,100%,100%) Output: (255,0,0)
Just i want add a progress bar for listening MySwingWorker's setProgress updates. When buton clicked swingworker should executed and progress bar should come to screen. I read many articles about that but not understand correctly. Because i am beginner in JAVA.
Question1: Should i (create new class) or (implement to current gui or swingworker class) for progressbar?
Question2: Should i fired progress bar first and execute swingworker from progressbar class? or should i execute swingworker first and fired progress bar later and how?
One of the four JDialog class would look something like this without the comments.
package client; import javax.swing.JDialog; @SuppressWarnings("serial") public class AddCustomerDialog extends JDialog implements Dialog{ public AddCustomerDialog () { //Some stuff goes here to set the settings for JDialog instance
I would like to be able to change the locale in my Swing application at runtime and have all the text elements on the GUI update themselves with localized text from a ResourceBundle of the new locale.If there a simple way of achieving this without having to create an event model for all GUI pages?
I have a assignment in which the code has to scrape a web page for a little bit of data including the link to the next page, follow the link, and do this 100 times. It is scraping all the data correctly, including the link, but it isn't following the link to scrape the data on that next page. Instead, it is displaying the first page's data 100 times. I have the code in a while loop where it reads in one character at a time from the page into a string and then uses pattern matching to get the data and the next link from the string. Then it correctly displays the data and should loop back to connect to that next link and read one character at a time into the string and so on.
I have printed the link to the console and it is good. I don't get any errors. I just can't figure out where exactly the problem is. Here is my code:
I have had to create a text analyser. I have created the program but it is all within the main method. The specification states that I have to have at least two methods within my Program.
import java.io.*; import java.text.SimpleDateFormat; import java.util.*; import javax.swing.*; import javax.swing.filechooser.FileNameExtensionFilter; public class Analyser { public static void main(String[] args) throws FileNotFoundException, UnsupportedEncodingException {
Code isn't giving me the output that I want and keeps giving me NaN
What I want -
Enter the A value for the line: 2.45 Enter the B value for the line: 4 Enter the C value for the line: -8 Enter the x coordinate of the point: 2.17 Enter the y coordinate of the point: -4
Distance from the point to the line is: 3.9831092774319026
What I am getting
Distance from the point to the line is: NaN
Here is my code-
Tester-
import java.io.*; import java.util.*; class tester { public static double A; public static double B; public static double C; public static double distance; public static void main(String args[])
