get a value from a textfield to use it on another class

[Jessica Nieves]

Hi!
Iam developing an application wich has a button named "Set Order". This button opens a dialog on which some options are set. The user has to enter some integer values (N, S, and R). I need to use the entered values on the principal class. How may I pass those values?? I tried using the following code on the dialog's class:


public String getParameters()
{
N = textfield1.getText();
return N;
}




and I call it using the following code from the principal class:

else if(command == "Set Order")
{
order = new setOrderDialog(this);
String N = order.getParameters();
}




The aboove code takes action when the "Set order" button is pressed.

This code gives me an exception, and I dont know other way to get that parameter. I know that the error is in that when it reads it reads text and it cannot be converted to integer, but I dont know how to fix it.

Please help as soon as possible!!!

JNP

[Norm]

When you get an error message and need some help to figure it out, you need to copy the full text of the message and paste it here. Also be sure to include the source program lines that generated that error.

Is your question: how to convert a String to an int?
See the Integer class. It has methods to convert a String to the int value it represents.
For example: int val = Integer.parseInt("123");

Norm

[Jessica Nieves]

When I press the Set Order button an exception occurs. I cant determine the nature of the exception... I may be calling wrong the getParameters method.
java 211:

public int getParameters()
{
String temp;
System.out.println("antes");
//this is line 211 on the dialog class
temp = textfield1.getText();
System.out.println(temp);
System.out.println("despues de leido");
N = Integer.parseInt(temp);
System.out.println("despues de convertido");
return N;
}






Java 219:

else if(command == "Set Order")
{
order = new setOrderDialog(this);
//this is line 219 on the princ. class

N = order.getParameters();
System.out.println(N);
}




This is the output window with the exception that it generates. The above code is the code that generates the exception:

antes
Exception occurred during event dispatching:
java.lang.NullPointerException
at setOrderDialog.getParameters(setOrderDialog.java:211)
at JavaFFT.actionPerformed(JavaFFT.java:219)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1450)
at javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(AbstractButton.java:1504)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:378)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:250)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:216)
at java.awt.Component.processMouseEvent(Component.java:3715)
at java.awt.Component.processEvent(Component.java:3544)
at java.awt.Container.processEvent(Container.java:1164)
at java.awt.Component.dispatchEventImpl(Component.java:2593)
at java.awt.Container.dispatchEventImpl(Container.java:1213)
at java.awt.Component.dispatchEvent(Component.java:2497)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:2451)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:2216)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:2125)
at java.awt.Container.dispatchEventImpl(Container.java:1200)
at java.awt.Window.dispatchEventImpl(Window.java:914)
at java.awt.Component.dispatchEvent(Component.java:2497)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:339)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:131)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:98)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:85)

JNP

[dlorde]

Where is textField1 initialized? The only way I can see for you to get that error on that line is if textField1 has not been initialized.

Incidentally, it's not advisable to have single letter variable names(e.g. 'N), except for local loop-counters and such. Java conventions also reserve capitalized data member names for constant values rather than variables.

Dave