Como adiciono uma barra de rolagem em um layout nulo?
https://stackoverflow.com//questions/21058395
-
22-12-2019 - |
italiano
english
français
española
中国
日本の
العربية
Deutsch
한국어
Português
RussianPergunta
Eu tenho tentado colocar uma barra de rolagem no meu JTextArea por dias, tentei de todas as maneiras que pude encontrar.Estou fazendo um cliente de chat e tenho o JPanel configurado com layout nulo.Tentei usar os Gerenciadores de Layout, mas não entendo como fazer com que fique do jeito que desejo.
Eu só quero uma barra de rolagem na área de texto.Sou iniciante e pelo que li não é possível ter um com layout nulo?Estou aberto para ajudar a mudar o layout, se isso também for mais fácil.
package guiserver;
import com.apple.eawt.Application;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
import javax.swing.WindowConstants;
public class GUIserver extends JFrame implements ActionListener {
JFrame login = new JFrame();
JPanel panel = new JPanel();
JPanel main = new JPanel();
JFrame accept = new JFrame();
JPanel acpt = new JPanel();
JPanel buttonpanel = new JPanel();
JButton acceptinvite = new JButton("Accept Invite");
JButton denyinvite = new JButton("Deny Invite");
JLabel acceptlabel = new JLabel();
JLabel acceptname = new JLabel();
JPanel loginpanel = new JPanel();
JTextArea chat = new JTextArea(" Waiting to Start Client...");
JSplitPane chatsplit = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
JTextField input = new JTextField();
JScrollPane pane = new JScrollPane(chat);
JButton send = new JButton("Send");
JLabel IP = new JLabel("IP:... ");
JButton start = new JButton("Start");
sendThread s1 = new sendThread();
fromThread f1 = new fromThread();
infoFromThread f2 = new infoFromThread();
infoToThread s2 = new infoToThread();
RPSpickTimer pt = new RPSpickTimer();
myCanvas contact = new myCanvas();
myCanvas logo = new myCanvas();
JButton rock = new JButton("Rock");
JButton paper = new JButton("Paper");
JButton scissors = new JButton("Scissors");
JTextField username = new JTextField();
JLabel loguser = new JLabel("Username:");
JLabel logpass = new JLabel("Password:");
JPasswordField password = new JPasswordField();
JButton signin = new JButton("Sign in");
String inputText = "0";
String chatCurrent;
String out1;
String in;
boolean pause = true;
boolean rps = false;
int P1pick = 0;
int P2pick = 0;
String user = "User 1";
String user2 = "Jacob Abthorpe";
String pass;
int badge;
int sendinvite = 0;
char answerinvite = '-';
boolean pauseInfo = true;
int winner = 0;
public GUIserver() {
Application application = Application.getApplication();
Image image = Toolkit.getDefaultToolkit().getImage("src/icon.png");
application.setDockIconImage(image);
login.setVisible(true);
login.setSize(400, 500);
login.setLocationRelativeTo(null);
login.setTitle("Login");
login.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
login.add(loginpanel);
loginpanel.setLayout(null);
loginpanel.add(username);
loginpanel.add(password);
loginpanel.add(signin);
loginpanel.add(logpass);
loginpanel.add(loguser);
loginpanel.add(logo);
login.setAlwaysOnTop(true);
username.setHorizontalAlignment(JTextField.CENTER);
password.setHorizontalAlignment(JTextField.CENTER);
username.setBounds(50, 290, 300, 30);
password.setBounds(50, 350, 300, 30);
loguser.setBounds(55, 265, 300, 30);
logpass.setBounds(55, 325, 300, 30);
signin.setBounds(150, 400, 100, 30);
logo.setBounds(110, 50, 150, 150);
username.addActionListener(this);
password.addActionListener(this);
signin.addActionListener(this);
setVisible(false);
setSize(500, 600);
setLocationRelativeTo(null);
setTitle("Chat Server Client");
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
setAlwaysOnTop(true);
panel.setLayout(null);
panel.setLocation(300, 0);
panel.add(pane);
panel.add(input);
panel.add(send);
panel.add(IP);
panel.add(start);
panel.add(rock);
panel.add(paper);
panel.add(scissors);
contact.picx = 120;
contact.picy = 120;
contact.setBackground(Color.white);
contact.setBounds(370, 10, 120, 120);
panel.add(contact);
input.addActionListener(this);
send.addActionListener(this);
start.addActionListener(this);
rock.addActionListener(this);
paper.addActionListener(this);
scissors.addActionListener(this);
chat.setEditable(false);
pane.setBounds(10, 10, 350, 450);
input.setEditable(false);
input.setBounds(10, 470, 350, 80);
start.setBounds(370, 470, 115, 80);
IP.setBounds(15, 520, 480, 80);
rock.setVisible(false);
paper.setVisible(false);
scissors.setVisible(false);
scissors.setBounds(370, 430, 115, 30);
paper.setBounds(370, 400, 115, 30);
rock.setBounds(370, 370, 115, 30);
setContentPane(panel);
accept.setVisible(false);
accept.setSize(400, 125);
accept.setLocationRelativeTo(null);
accept.setTitle("Rock, Paper, Scissors");
accept.setAlwaysOnTop(true);
accept.setResizable(false);
accept.add(acpt);
acpt.setLayout(null);
acpt.add(acceptlabel);
acpt.add(buttonpanel);
acpt.add(acceptname);
buttonpanel.setBounds(0, 60, 400, 40);
buttonpanel.setLayout(new FlowLayout());
acceptlabel.setHorizontalAlignment(SwingConstants.CENTER);
acceptlabel.setText("would like to play Rock, Paper, Scissors. Accept?");
acceptlabel.setBounds(0, 25, 400, 40);
acceptname.setHorizontalAlignment(SwingConstants.CENTER);
acceptname.setText(user2 + "");
acceptname.setBounds(0, 3, 400, 40);
buttonpanel.add(acceptinvite);
buttonpanel.add(denyinvite);
acceptinvite.addActionListener(this);
denyinvite.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == input) {
if (input.getText().startsWith("/")) {
if (input.getText().contentEquals("/")) {
chat.append("\n\n >Type '/help' for list of all commands");
}
if (input.getText().contentEquals("/start RPS")) {
chat.append("\n \n >Waiting for opponent to accept invite. . .");
pauseInfo = false;
sendinvite = 10;
}
if (input.getText().contentEquals("/help")) {
chat.append("\n\n >Type '/help' for list of all commands");
chat.append("\n >Type '/start RPS' to play Rock Paper Scissors");
chat.append("\n >Type '/end' to quit current game");
}
if (input.getText().contentEquals("/end")) {
if (rps == true) {
chat.append("\n\n >Quiting Rock, Paper, Scissors. . .");
rps = false;
rock.setVisible(false);
paper.setVisible(false);
scissors.setVisible(false);
}
}
input.setText("");
} else {
if ((input.getText().contentEquals("")) && (input.getText().contentEquals(" "))) {
Toolkit.getDefaultToolkit().beep();
} else {
pause = false;
chat.append("\n \n " + user + " says: \n " + input.getText());
inputText = input.getText();
input.setText("");
}
}
}
if (e.getSource() == send) {
//chat.append("\n \n Dale Schmidt says: \n " + inputText);
//pause = false;
}
if (e.getSource() == username) {
user = username.getText();
}
if (e.getSource() == signin) {
login.setVisible(false);
setVisible(true);
}
if (e.getSource() == start) {
try {
s1.start();
f1.start();
s2.start();
f2.start();
setAlwaysOnTop(false);
chat.append("\n " + InetAddress.getLocalHost() + "\n Server started.");
IP.setText("IP: " + InetAddress.getLocalHost());
start.setVisible(false);
send.setVisible(true);
input.setEditable(true);
send.setBounds(370, 470, 115, 80);
} catch (Exception s) {
System.out.print("YOLOerror starting server");
}
}
if (e.getSource() == rock) {
if ((rps == true) && (P1pick == 0)) {
P1pick = 1;
chat.append("\n\n >You picked 'Rock'");
if (P2pick != 0) {
pt.start();
}
}
}
if (e.getSource() == paper) {
if ((rps == true) && (P1pick == 0)) {
P1pick = 2;
chat.append("\n\n >You picked 'Paper'");
if (P2pick != 0) {
pt.start();
}
}
}
if (e.getSource() == scissors) {
if ((rps == true) && (P1pick == 0)) {
P1pick = 3;
chat.append("\n\n >You picked 'Scissors'");
if (P2pick != 0) {
pt.start();
}
}
}
if (e.getSource() == acceptinvite) {
rps = true;
rock.setVisible(true);
paper.setVisible(true);
scissors.setVisible(true);
answerinvite = 'y';
accept.dispose();
}
if (e.getSource() == denyinvite) {
answerinvite = 'n';
accept.dispose();
}
}
class myCanvas extends Canvas {
int x = 10, y = 10;
int picx = 150, picy = 150;
public void paint(Graphics g) {
Image image1 = Toolkit.getDefaultToolkit().getImage("src/icon.png");
g.drawImage(image1, x, y, picx, picy, this);
}
}
class sendThread extends Thread {
ServerSocket s1;
Socket sendclientSocket = null;
public void run() {
inputText = input.getText();
try {
System.err.println("Starting Send Server");
System.out.println(InetAddress.getLocalHost());
s1 = new ServerSocket(4444);
sendclientSocket = s1.accept();
System.err.println("Started Send Server");
} catch (Exception s1) {
System.exit(1);
}
while (true) {
try {
PrintWriter out = new PrintWriter(sendclientSocket.getOutputStream(), true);
if (pause == false) {
badge = 0;
out.println(input.getText());
System.out.println("sent");
pause = true;
}
} catch (Exception e) {
System.err.println("Error Sending.");
System.err.println(e.getMessage());
System.exit(2);
}
}
}
}
class fromThread extends Thread {
ServerSocket s2;
Socket fromclientSocket = null;
public void run() {
try {
System.err.println("Starting Recieve Server");
s2 = new ServerSocket(4441);
fromclientSocket = s2.accept();
System.err.println("Started Recieve Server");
} catch (Exception s2) {
System.exit(1);
}
while (true) {
try {
BufferedReader in = new BufferedReader(new InputStreamReader(fromclientSocket.getInputStream()));
String fromClient = in.readLine();
if (fromClient.contentEquals("")) {
} else {
Toolkit.getDefaultToolkit().beep();
chat.append("\n\n " + user2 + " says:\n " + fromClient);
badge++;
Application.getApplication().setDockIconBadge(Integer.toString(badge));
}
} catch (Exception e) {
System.err.println("Error Receiving.");
System.err.println(e.getMessage());
System.exit(3);
}
}
}
}
class infoFromThread extends Thread {
ServerSocket s3;
Socket infoFromClientSocket = null;
public void run() {
try {
s3 = new ServerSocket(4446);
infoFromClientSocket = s3.accept();
} catch (Exception s3) {
System.exit(7);
}
while (true) {
try {
BufferedReader in = new BufferedReader(new InputStreamReader(infoFromClientSocket.getInputStream()));
String infoFromClient = in.readLine();
if (infoFromClient.contentEquals("10")) {
accept.setVisible(true);
sendinvite = 0;
} else if (infoFromClient.contentEquals("y")) {
chat.append("\n >Invite Accepted");
rps = true;
rock.setVisible(true);
paper.setVisible(true);
scissors.setVisible(true);
answerinvite = '-';
} else if (infoFromClient.contentEquals("n")) {
chat.append("\n\n >Invite Declined");
answerinvite = '-';
} else if (infoFromClient.contentEquals("1")) {
chat.append("\n\n >Opponent made selection");
P2pick = 1;
if (P1pick != 0) {
pt.start();
}
} else if (infoFromClient.contentEquals("2")) {
chat.append("\n\n >Opponent made selection");
P2pick = 2;
if (P1pick != 0) {
pt.start();
}
} else if (infoFromClient.contentEquals("3")) {
chat.append("\n\n >Opponent made selection");
P2pick = 3;
if (P1pick != 0) {
pt.start();
}
}
} catch (Exception e) {
System.err.println("Error Receiving Information.");
System.err.println(e.getMessage());
System.exit(3);
}
}
}
}
class infoToThread extends Thread {
ServerSocket s4;
Socket infoToClientSocket = null;
public void run() {
inputText = input.getText();
try {
s4 = new ServerSocket(4447);
infoToClientSocket = s4.accept();
} catch (Exception s4) {
System.exit(8);
}
while (true) {
try {
PrintWriter out = new PrintWriter(infoToClientSocket.getOutputStream(), true);
if (sendinvite == 10) {
out.println(sendinvite);
sendinvite = 0;
pauseInfo = false;
}
if ((answerinvite == 'y') || (answerinvite == 'n')) {
out.println(answerinvite);
answerinvite = '-';
}
if (winner == 1) {
out.println("Loser");
}
else if (winner == 2) {
out.println("Winner");
}
else if (winner == 3) {
out.println("Tie");
}
//winner = 0;
//System.err.println("infoToClient");
} catch (Exception e) {
System.err.println("Error Sending Information.");
System.err.println(e.getMessage());
System.exit(2);
}
}
}
}
class RPSpickTimer extends Thread {
public void run() {
while (true) {
try {
if (P1pick != 0) {
if (P1pick == 1) {
if (P2pick == 1) {
//tie
chat.append("\n\n Tie!");
winner = 3;
} else if (P2pick == 2) {
//P2wins
chat.append("\n\n " + user2 + " wins!");
winner = 2;
} else if (P2pick == 3) {
//P1wins
chat.append("\n\n " + user + " wins!");
winner = 1;
}
} else if (P1pick == 2) {
if (P2pick == 1) {
//P1wins
chat.append("\n\n " + user + " wins!");
winner = 1;
} else if (P2pick == 2) {
//tie
chat.append("\n\n Tie!");
winner = 3;
} else if (P2pick == 3) {
//P2wins
chat.append("\n\n " + user2 + " wins!");
winner = 2;
}
} else if (P1pick == 3) {
if (P2pick == 1) {
//P2wins
chat.append("\n\n " + user2 + " wins!");
winner = 2;
} else if (P2pick == 2) {
//P1wins
chat.append("\n\n " + user + " wins!");
winner = 1;
} else if (P2pick == 3) {
//tie
chat.append("\n\n Tie!");
winner = 3;
}
}
P1pick = 0;
P2pick = 0;
}
else {
sleep(250);
}
} catch (Exception e) {
System.err.println("Error Picking Winner.");
System.err.println(e.getMessage());
System.exit(2);
}
}
}
}
public static void main(String[] args) {
GUIserver s = new GUIserver();
}`
Solução
Está linha:
panel.add(chat);
Em vez de adicionar chat, adicionar pane, como:
panel.add(pane);
Outras dicas
De JTextArea docs "O java.awt.TextArea lida internamente com a rolagem.JTextArea é diferente porque não gerencia a rolagem, mas implementa a interface swing Scrollable.Isso permite que ele seja colocado dentro de um JScrollPane se o comportamento de rolagem for desejado e usado diretamente se a rolagem não for desejada."
Acho que isso significa que é isso que você quer:
JTextArea chat = new JTextArea(" Waiting to Start Client...");
JScrollPane chatScrollPane = new JScrollPane(chat);
...
panel.setLocation(300, 0);
panel.add(chatScrollPane);
panel.add(input);
Como destacou Nicolás Carlo, você já tem o JScrollPane e só precisa adicioná-lo no lugar do JTextArea.Basicamente, o sistema Java UI (e a maioria dos sistemas UI) é uma árvore gigante de widgets.Se você não adicionar um widget à árvore, isso não terá efeito.Nesse caso, o JScrollPane não estava sendo adicionado à árvore e, portanto, não estava fazendo nada por você.
Isto não é uma resposta, mas uma demonstração de como um LayoutManager pode ser usado para alcançar os resultados do PO
Então, com base no seu exemplo de código, recebo esta saída ...
Espero que você note que o quadro não é grande o suficiente para conter o conteúdo, este é o maior problema com null layouts, eles nunca parecem iguais em outros sistemas...
E ao utilizar um GridBagLayout e um GridLayout e um conceito conhecido como "layouts compostos", consegui zombar disso...
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Insets;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class ChatLayout {
public static void main(String[] args) {
new ChatLayout();
}
public ChatLayout() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new ChatPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class ChatPane extends JPanel {
private JTextArea chatWindow;
private JTextField input;
private JLabel ipLabel;
private JButton rockBtn;
private JButton paperBtn;
private JButton scissorsBtn;
private JButton startBtn;
public ChatPane() {
JPanel leftPane = new JPanel(new GridBagLayout());
JPanel rightPane = new JPanel(new GridBagLayout());
chatWindow = new JTextArea(20, 40);
chatWindow.setText("Waiting to start chat...");
input = new JTextField(10);
ipLabel = new JLabel("IP...");
rockBtn = new JButton("Rock");
paperBtn = new JButton("Paper");
scissorsBtn = new JButton("Scissors");
startBtn = new JButton("Start");
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(4, 4, 4, 4);
gbc.gridx = 0;
gbc.gridy = 0;
gbc.fill = GridBagConstraints.BOTH;
gbc.weighty = 1;
gbc.weightx = 1;
leftPane.add(new JScrollPane(chatWindow), gbc);
gbc.gridy++;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.weighty = 0;
gbc.weightx = 1;
gbc.gridheight = 1;
leftPane.add(input, gbc);
gbc.gridy++;
gbc.fill = GridBagConstraints.HORIZONTAL;
leftPane.add(ipLabel, gbc);
JPanel buttonsPane = new JPanel(new GridLayout(3, 1));
buttonsPane.add(rockBtn);
buttonsPane.add(paperBtn);
buttonsPane.add(scissorsBtn);
gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.anchor = GridBagConstraints.SOUTH;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.weighty = 1;
rightPane.add(buttonsPane, gbc);
gbc.gridy++;
gbc.insets = new Insets(8, 0, 0, 0);
gbc.fill = GridBagConstraints.BOTH;
gbc.anchor = GridBagConstraints.CENTER;
gbc.weighty = 0;
gbc.gridheight = 2;
gbc.ipadx = 30;
gbc.ipady = 30;
rightPane.add(startBtn, gbc);
gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
add(leftPane, gbc);
gbc.gridx++;
gbc.weightx = 0;
gbc.weighty = 1;
add(rightPane, gbc);
}
}
}
Agora, este é apenas um exemplo.Suas necessidades podem ser diferentes, o que exigiria o uso de diferentes gerenciadores de layout ou em diferentes combinações ...
Licenciado em: CC-BY-SA com atribuição
Não afiliado a StackOverflow
