如何在Java中禁用GUI按钮

Question

so I have this small piece of code for my GUI:

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.BoxLayout;
import javax.swing.JSeparator;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;


public class IPGUI extends JFrame implements ActionListener 
{
    private static JPanel contentPane;
    private static boolean btn1Clicked = false;
    private static boolean btn2Clicked = false;
    private static boolean btn3Clicked = false;
    private static boolean btn4Clicked = false;

    //Create the frame
    public IPGUI() 
    {
        //Sets frame properties
        setTitle("IP Extractor");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 250, 300);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        contentPane.setLayout(new BorderLayout(0, 0));
        setContentPane(contentPane);

        //Creates new JPanel with boxlayout
        JPanel panel = new JPanel();
        contentPane.add(panel, BorderLayout.CENTER);
        panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));

        //////////////////New Button//////////////////

        JButton btnConvertDocuments = new JButton("1. Convert Documents");
        btnConvertDocuments.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnConvertDocuments.setMaximumSize(new Dimension(160, 0));
        btnConvertDocuments.setPreferredSize(new Dimension(0, 50));

        panel.add(btnConvertDocuments);

        btnConvertDocuments.setActionCommand("w");
        btnConvertDocuments.addActionListener((ActionListener) this);

        if (btn1Clicked == true)
        {
            btnConvertDocuments.setEnabled(false);
        }

        JSeparator separator_3 = new JSeparator();
        panel.add(separator_3);

        //////////////////New Button//////////////////

        JButton btnExtractImages = new JButton("2. Extract Images");
        btnExtractImages.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnExtractImages.setMaximumSize(new Dimension(160, 0));
        btnExtractImages.setPreferredSize(new Dimension(0, 50));

        panel.add(btnExtractImages);

        btnExtractImages.setActionCommand("x");
        btnExtractImages.addActionListener((ActionListener) this);

         if (btn2Clicked == true)
         {
             btnExtractImages.setEnabled(false);
         }

        JSeparator separator_2 = new JSeparator();
        panel.add(separator_2);

        //////////////////New Button//////////////////

        JButton btnParseRIDValues = new JButton("3. Parse rId Values");
        btnParseRIDValues.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnParseRIDValues.setMaximumSize(new Dimension(160, 0));
        btnParseRIDValues.setPreferredSize(new Dimension(0, 50));

        panel.add(btnParseRIDValues);

        btnParseRIDValues.setActionCommand("y");
        btnParseRIDValues.addActionListener((ActionListener) this);

        if (btn3Clicked == true)
        {
            btnParseRIDValues.setEnabled(false);
        }

        JSeparator separator_1 = new JSeparator();
        panel.add(separator_1);

        //////////////////New Button//////////////////

        JButton btnParseImageInfo = new JButton("4. Parse Image Info.");
        btnParseImageInfo.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnParseImageInfo.setMaximumSize(new Dimension(160, 0));
        btnParseImageInfo.setPreferredSize(new Dimension(0, 50));

        panel.add(btnParseImageInfo);

        btnParseImageInfo.setActionCommand("z");
        btnParseImageInfo.addActionListener((ActionListener) this);

        if (btn4Clicked == true)
        {
            btnParseImageInfo.setEnabled(false);
        }
    }

    public void actionPerformed(ActionEvent event) 
    {
        String command = event.getActionCommand();

        if (command.equals("w"))
        {
            FileConverter fc = new FileConverter();
            btn1Clicked = true;
        }
        else if (command.equals("x"))
        {
            ImageExtractor ie = new ImageExtractor();
            btn2Clicked = true;
        }
        else if (command.equals("y")) 
        {
            XMLIDParser xip = new XMLIDParser();
            btn3Clicked = true;
        }
        else if (command.equals("z")) 
        {
            XMLTagParser xtp = new XMLTagParser();
            btn4Clicked = true;
        }
    }    
}

The part I want to focus specifically, is this conditional:

 if (btn1Clicked == true)
        {
            btnConvertDocuments.setEnabled(false);
        }

So my belief is that what that command should do is this: once the button is clicked and the action performed method is called, btnClicked should be set to true, thus that button should then become disabled.

Can someone explain where am I going wrong here, or if I have the right idea here? Thank you in advance for any input!

Answer 1

You should put the statement btnConvertDocuments.setEnabled(false); in the actionPerformed(ActionEvent event) method. Your conditional above only get call once in the constructor when IPGUI object is being instantiated.

if (command.equals("w")) {
    FileConverter fc = new FileConverter();
    btn1Clicked = true;
    btnConvertDocuments.setEnabled(false);
}

Answer 2

really that not possible to disable JComponent(s) if output to the GUI is invoked from Listener , in all of cases, all events are inside EDT including setEnabled/setVisible ,

JComponent(s) is/are disabled/visible if all Events in EDT ends,

there are there ways

1/ safiest way would be look for GlassPane , which prevents after all MouseEvents (not KeyEvents ) best code around is by camickr's

2/ use multithreading with SwingWorker for separate and delay concrete event(s), Action from JComponent -> disable JComponent(s) in GUI -> then required Action , but there (if is possible to adds) you have to identify all actions by using myAction#putProperty("String","String")

3/ put Enabled/Visible to the invokeLater() and all Action from Listener must be wrapped into invokeAndWait()

4/ inside Runnable()#Thread

Answer 3

Rather than using booleans, why not just set the button to false when its clicked, so you do that in your actionPerformed method. Its more efficient..

if (command.equals("w"))
{
    FileConverter fc = new FileConverter();
    btnConvertDocuments.setEnabled(false);
}

Answer 4

Once you've created the frame the part of the code with your conditional isn't going to get entered. To put it another way, at the time you execute the test if (btn1Clicked == true) , the button has not only not been clicked yet, it hasn't even been displayed to the user.

Lose the booleans and move the line with the btnConvertDocuments.setEnabled(false) into your actionListener. Make the buttons instance variables, do not make them static variables. (Alternatively you could keep the buttons as local variables and assign each of them their own anonymous inner class listener.)

Answer 5

You create the frame with button enable, do some test to see if btn1Cliked is true, and that's all.

Then you have the actionPerformed method that does nothing with your button. So, if you don't have any action related, your button status will never be evaluated again.

Answer 6

Is there a reason you are not doing something like:

public class IPGUI extends JFrame implements ActionListener 
{
    private static JPanel contentPane;

    private JButton btnConvertDocuments;
    private JButton btnExtractImages;
    private JButton btnParseRIDValues;
    private JButton btnParseImageInfo;

    public IPGUI() 
    {
        ...

        btnConvertDocuments = new JButton("1. Convert Documents");

        ...

        btnExtractImages = new JButton("2. Extract Images");

        ...

        //etc.
    }

    public void actionPerformed(ActionEvent event) 
    {
        String command = event.getActionCommand();

        if (command.equals("w"))
        {
            FileConverter fc = new FileConverter();
            btnConvertDocuments.setEnabled( false );
        }
        else if (command.equals("x"))
        {
            ImageExtractor ie = new ImageExtractor();
            btnExtractImages.setEnabled( false );
        }

        // etc.
    }    
}

The if statement with your disabling code won't get called unless you keep calling the IPGUI constructor.

Answer 7

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.BoxLayout;
import javax.swing.JSeparator;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;


public class IPGUI extends JFrame implements ActionListener 
{
    private static JPanel contentPane;

    private JButton btnConvertDocuments;
    private JButton btnExtractImages;
    private JButton btnParseRIDValues;
    private JButton btnParseImageInfo;

    //Create the frame
    public IPGUI() 
    {
        //Sets frame properties
        setTitle("IP Extractor");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 250, 300);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        contentPane.setLayout(new BorderLayout(0, 0));
        setContentPane(contentPane);

        //Creates new JPanel with boxlayout
        JPanel panel = new JPanel();
        contentPane.add(panel, BorderLayout.CENTER);
        panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));

        //////////////////New Button//////////////////

        JButton btnConvertDocuments = new JButton("1. Convert Documents");
        btnConvertDocuments.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnConvertDocuments.setMaximumSize(new Dimension(160, 0));
        btnConvertDocuments.setPreferredSize(new Dimension(0, 50));

        panel.add(btnConvertDocuments);

        btnConvertDocuments.setActionCommand("w");
        btnConvertDocuments.addActionListener((ActionListener) this);

        JSeparator separator_3 = new JSeparator();
        panel.add(separator_3);

        //////////////////New Button//////////////////

        btnExtractImages = new JButton("2. Extract Images");
        btnExtractImages.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnExtractImages.setMaximumSize(new Dimension(160, 0));
        btnExtractImages.setPreferredSize(new Dimension(0, 50));

        panel.add(btnExtractImages);

        btnExtractImages.setActionCommand("x");
        btnExtractImages.addActionListener((ActionListener) this);

        JSeparator separator_2 = new JSeparator();
        panel.add(separator_2);

        //////////////////New Button//////////////////

        JButton btnParseRIDValues = new JButton("3. Parse rId Values");
        btnParseRIDValues.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnParseRIDValues.setMaximumSize(new Dimension(160, 0));
        btnParseRIDValues.setPreferredSize(new Dimension(0, 50));

        panel.add(btnParseRIDValues);

        btnParseRIDValues.setActionCommand("y");
        btnParseRIDValues.addActionListener((ActionListener) this);

        JSeparator separator_1 = new JSeparator();
        panel.add(separator_1);

        //////////////////New Button//////////////////

        JButton btnParseImageInfo = new JButton("4. Parse Image Info.");
        btnParseImageInfo.setAlignmentX(Component.CENTER_ALIGNMENT);
        btnParseImageInfo.setMaximumSize(new Dimension(160, 0));
        btnParseImageInfo.setPreferredSize(new Dimension(0, 50));

        panel.add(btnParseImageInfo);

        btnParseImageInfo.setActionCommand("z");
        btnParseImageInfo.addActionListener((ActionListener) this);
    }

    public void actionPerformed(ActionEvent event) 
    {
        String command = event.getActionCommand();

        if (command.equals("w"))
        {
            FileConverter fc = new FileConverter();
            btnConvertDocuments.setEnabled(false);
        }
        else if (command.equals("x"))
        {
            ImageExtractor ie = new ImageExtractor();
            btnExtractImages.setEnabled(false);
        }
        else if (command.equals("y")) 
        {
            XMLIDParser xip = new XMLIDParser();
            btnParseRIDValues.setEnabled(false);
        }
        else if (command.equals("z")) 
        {
            XMLTagParser xtp = new XMLTagParser();
            btnParseImageInfo.setEnabled(false);        
        }
    }


}

Here is the solution I came up with thanks to everyone's help. Thank you again everyone for your input, really appreciate it!

Answer 8

Rather than using booleans, why not just set the button to false when its clicked, so you do that in your actionPerformed method. Its more efficient..

if (command.equals("w"))
{
    FileConverter fc = new FileConverter();
    btnConvertDocuments.setEnabled(false);
}