My program fills combo boxes from database and it's kinf of slow
I want my window to open in split second but it takes like 1-2 seconds.
So I'm thinking maby I should get all necessery variables loaded before I open any windows?
Because I have 5 windows and more in future then where should I save my data so that all windows have acces to it?
What would you do to make this app as fast as it can go?
> You can remove database access from the EDT (event
> dispatch thread):
>
> http://java.sun.com/docs/books/tutorial/uiswing/concur
> rency/index.html
I red it briefly but don't undrestand it very well.
This is what I thought I could do to make my program faster. I need your opinion.
A PreLoad class that gets all necesseray data loaded in the beginning. When I open a new window I pass it on like this:
My Window = w new MyWindow(PreLoad instance initialized somewhere before this line);
Maby I even load a full window into PreLoad instance and make copy of it every time I need to initialize a new window?
But maby I just have to read EDT again?
> How would you initialize a window so that it appears in zero time?
JFrame f = new JFrame(title);
... compose f ...
f.pack();
//f is now ready to be made visible.
When you need to see f:
f.setVisible(true);
> > How would you initialize a window so that it
> appears in zero time?
>
> > JFrame f = new JFrame(title);
> ... compose f ...
> f.pack();
> //f is now ready to be made visible.
>
> When you need to see f:
> > f.setVisible(true);
>
Sounds like a plan - Load all Windows during program boot or in background (not really sure yet how to do the last 1. goin' to read about even threads again)
But when I close a window, I dispose it and need to open it again. I try to initialize new window during close?
Hm... or maby do reset() function that just resets fields and hides again?
And another question. This is wrong:
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
MainWindow w1 = new MainWindow();
w1.setVisible(true);
}
});
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
MainWindow w2 = new MainWindow();
w2.setVisible();
}
});
Compiles but does not open 2 windows.
/*
* Init.java
*
* Created on April 25, 2007, 3:08 AM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/
package Kernel;
import GUI.*;
/**
*
* @author hannes
*/
public class Init {
/** Creates a new instance of Init */
public Init() {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
MainWindow w1 = new MainWindow();
w1.setVisible(true);
}
});
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
MainWindow w2 = new MainWindow();
w2.setVisible(true);
}
});
}
public static void main(String[] args) {
// TODO code application logic here
}
}
I tried compiling your code, but I get these errors:
...\Init.java:7: cannot find symbol
symbol: class MainWindow
MainWindow w1 = new MainWindow();
^
...\Init.java:7: cannot find symbol
symbol: class MainWindow
MainWindow w1 = new MainWindow();
^
...\Init.java:14: cannot find symbol
symbol: class MainWindow
MainWindow w2 = new MainWindow();
^
...\Init.java:14: cannot find symbol
symbol: class MainWindow
MainWindow w2 = new MainWindow();
^
4 errors
> MainWinow is just a empty window. I guess I can write
> a simple version if u don't have netbeans
This may amaze you, but I am able to write code without an IDE :-) For example:
import javax.swing.*;
class MainWindow extends JFrame {
public MainWindow() {
setSize(100,100);
}
}
public class Init {
public Init() {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
MainWindow w1 = new MainWindow();
w1.setVisible(true);
}
});
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
MainWindow w2 = new MainWindow();
w2.setVisible(true);
}
});
}
public static void main(String[] args) {
new Init();
}
}
I gave the windows size 100x100 so that they are easier to spot. If you see only one, it's because they are stacked.
