This is eating my lunch. There is a lot of code here, and the problem lies somewhere with not being able to convince the SpringLayout layout manager that he needs to recheck his constraints.
First, the file name should be MySLO.java.
The problem lies with the JTextArea in the middle of the application window. If the window is resized, the layout goes awry.
When the window is resized to the right:
So far, so good.
However, when the window is resized to the left:
All this occurs when JTextArea.setLineWrap(true) is set.
If setLineWrap(false) is set, the behavior changes:
When the window is resized left or right, all buttons and the label stay where they are supposed to, and the JTextArea is resized properly.
However, when you type, you get no line wrapping, and the box is now worthless for long phrases. I guess, this scenario is working as designed. But, I need the line wrap, so it's not really applicable to my needs.
Here's the code. If you can figure this out, I owe you a beer (or a kool-aid!
)
Todd
p.s.
First, the file name should be MySLO.java.
The problem lies with the JTextArea in the middle of the application window. If the window is resized, the layout goes awry.
When the window is resized to the right:
- all buttons and the label stay put as desired, and
- the JTextArea expands to the right as desired.
So far, so good.
However, when the window is resized to the left:
- all buttons and the label will move to the right (evensomuch as off-screen) and
- the JTextArea is not resized smaller to fix how the constraints are defined.
All this occurs when JTextArea.setLineWrap(true) is set.
If setLineWrap(false) is set, the behavior changes:
When the window is resized left or right, all buttons and the label stay where they are supposed to, and the JTextArea is resized properly.
However, when you type, you get no line wrapping, and the box is now worthless for long phrases. I guess, this scenario is working as designed. But, I need the line wrap, so it's not really applicable to my needs.
Here's the code. If you can figure this out, I owe you a beer (or a kool-aid!
) Todd
p.s.
- newbie warning with Java...
- Code in question is RED
- I've used adapter classes for the buttons
Code:
// My SpringLayOut bug.
public class MySLO extends javax.swing.JFrame {
static javax.swing.JTextArea myText ;
// Create a window with all the GUI stuff, and display it.
public static void main(String[] args) {
javax.swing.JFrame win = new MySLO() ;
win.setVisible(true) ; // make window appear
}
// This is the GUI window maker. It builds the buttons, does the layout,
// registers for events, etc...
public MySLO() {
super("My SpringLayout Bug - Stretch Window to the Right, then Left, to see the bug") ; // This is the window title
// Get the JFrame's container.
java.awt.Container content = this.getContentPane() ;
// Set the Layout Manager
javax.swing.SpringLayout myLayout = new javax.swing.SpringLayout() ;
content.setLayout(myLayout) ;
// Connect and Disconnnect Buttons.
javax.swing.JButton buttonConnect = new javax.swing.JButton("Connect") ;
buttonConnect.addActionListener(new ButtonConnect(this)) ;
content.add(buttonConnect) ;
javax.swing.JButton buttonDisconnect = new javax.swing.JButton("Disconnect") ;
buttonDisconnect.addActionListener(new ButtonDisconnect(this)) ;
content.add(buttonDisconnect) ;
// This is the label for the box that is screwing up
javax.swing.JLabel enterLabel = new javax.swing.JLabel() ;
enterLabel.setText("Enter Text:") ;
content.add(enterLabel) ;
[color=red][b]// This is the JTextArea box that is screwing up
myText = new javax.swing.JTextArea(10,50) ;
// If this setLineWrap is set to false, the problem is that the TextArea grows to the right
// while the window stays the same size. Pretty soon, you can't see what you type.
// If this setLineWrap is set to true, there is an issue with resizing the whole window - all
// the other widgets move incorrectly, and this TextArea can grow but will never shrink.
myText.setLineWrap(true) ; // Cause it to wrap lines. Change to false for no line wrap.
// Add a listener so I can force a validation of the layout - but it has no effect... :(
myText.addComponentListener(new java.awt.event.ComponentListener() {
public void componentResized(java.awt.event.ComponentEvent e) {
System.out.println("Validating...") ;
validate() ; // In theory, this should validate the layout!!
}
public void componentShown(java.awt.event.ComponentEvent e ) { }
public void componentMoved(java.awt.event.ComponentEvent e ) { }
public void componentHidden(java.awt.event.ComponentEvent e) { }
} ) ;
content.add(myText) ;[/b][/color]
javax.swing.JButton buttonClear = new javax.swing.JButton("Clear") ;
buttonClear.addActionListener(new ButtonClear(this)) ;
content.add(buttonClear) ;
javax.swing.JButton buttonSubmit = new javax.swing.JButton("Submit") ;
buttonSubmit.addActionListener(new ButtonSubmit(this)) ;
content.add(buttonSubmit);
this.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE) ; // Close app when RED X is clicked.
// The following code sets up the Spring Layout Constraints - it positions everything
// in the window and influences object placement when the window is resized.
// Row 1 - Constrain to the Top & Left Edge
myLayout.putConstraint(javax.swing.SpringLayout.WEST, buttonConnect, 135, javax.swing.SpringLayout.WEST, content);
myLayout.putConstraint(javax.swing.SpringLayout.NORTH, buttonConnect, 15, javax.swing.SpringLayout.NORTH, content);
myLayout.putConstraint(javax.swing.SpringLayout.WEST, buttonDisconnect, 15, javax.swing.SpringLayout.EAST, buttonConnect);
myLayout.putConstraint(javax.swing.SpringLayout.NORTH, buttonDisconnect, 15, javax.swing.SpringLayout.NORTH, content);
// Row 2 - Constrain to the Top and Left Edge.
myLayout.putConstraint(javax.swing.SpringLayout.EAST, enterLabel, 120, javax.swing.SpringLayout.WEST, content);
myLayout.putConstraint(javax.swing.SpringLayout.NORTH, enterLabel, 50, javax.swing.SpringLayout.NORTH, content);
myLayout.putConstraint(javax.swing.SpringLayout.WEST, myText, 135, javax.swing.SpringLayout.WEST, content);
myLayout.putConstraint(javax.swing.SpringLayout.NORTH, myText, 50, javax.swing.SpringLayout.NORTH, content);
// Row 3 - Constrain to the Top and Left Edge
myLayout.putConstraint(javax.swing.SpringLayout.WEST, buttonClear, 135, javax.swing.SpringLayout.WEST, content);
myLayout.putConstraint(javax.swing.SpringLayout.NORTH, buttonClear, 15, javax.swing.SpringLayout.SOUTH, myText);
myLayout.putConstraint(javax.swing.SpringLayout.WEST, buttonSubmit, 15, javax.swing.SpringLayout.EAST, buttonClear);
myLayout.putConstraint(javax.swing.SpringLayout.NORTH, buttonSubmit, 15, javax.swing.SpringLayout.SOUTH, myText);
// Constrain to the Bottom.
myLayout.putConstraint(javax.swing.SpringLayout.SOUTH, content, 15, javax.swing.SpringLayout.SOUTH, buttonSubmit);
// Constrain to the right Edge
myLayout.putConstraint(javax.swing.SpringLayout.EAST, content, 20, javax.swing.SpringLayout.EAST, myText);
this.pack() ; // Resize the window as needed.
// Center the Dialog on the screen.
java.awt.Dimension screen = java.awt.Toolkit.getDefaultToolkit().getScreenSize() ;
int x = (screen.width - this.getWidth() ) / 2 ;
int y = (screen.height - this.getHeight() ) / 2 ;
setBounds(x,y,this.getWidth(),this.getHeight()) ;
}
// Adapter Classes - to separate the GUI from the application logic (not that there IS any appl. logic yet...
class ButtonClear implements java.awt.event.ActionListener {
MySLO data ;
ButtonClear (MySLO data ) {
this.data = data ;
}
public void actionPerformed( java.awt.event.ActionEvent ae) {
data.myText.setText("") ;
System.out.println("Input data has been cleared") ;
}
}
class ButtonSubmit implements java.awt.event.ActionListener {
MySLO data ;
ButtonSubmit (MySLO data ) {
this.data = data ;
}
public void actionPerformed( java.awt.event.ActionEvent ae) {
System.out.println("Submit Button") ;
}
}
class ButtonConnect implements java.awt.event.ActionListener {
MySLO data ;
ButtonConnect (MySLO data ) {
this.data = data ;
}
public void actionPerformed( java.awt.event.ActionEvent ae) {
System.out.println("Connect Button") ;
}
}
class ButtonDisconnect implements java.awt.event.ActionListener {
MySLO data ;
ButtonDisconnect (MySLO data ) {
this.data = data ;
}
public void actionPerformed( java.awt.event.ActionEvent ae) {
System.out.println("Disconnect Button") ;
}
}
}
