我想在JPanel上绘制线条和更多内容,将其添加到JFrame并随后使用。pack()。我的问题是在这种情况下,我不知道如何使用布局管理器。通常,我使用gridBagLayout向面板添加按钮或其他东西,我完全理解这一点。但是对于2D图形,我只是直接绘制到面板上。因此,我无法正确使用.pack()。有人知道如何以正确的方式pack()jPanel吗?我的代码如下所示:
public class NetworkViewPanel extends JPanel implements KeyListener, ActionListener {
public NetworkViewPanel(NetworkAI network) {
this.network = network;
this.netList = network.getLayerList();
addKeyListener(this);
setFocusable(true);
this.setLayout(new GridLayout(2, 2, 2, 2)); // does that even make sense ?
}
public void paint(Graphics g) {
super.paint(g);
g2 = (Graphics2D) g;
if (showStandardView) {
drawRectangles();
drawLines();
} else {
drawRectangles();
drawLinesSpecial(listIndex, xIndex);
}
}
问候:)
您可以使用布局管理器来布局JPanel
,并在其上方进行自定义绘制。这不会阻止您使用pack()
。以下mre 1演示了使用JPanel
在GridLayout
上绘制线条:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.util.ArrayList;
import java.util.List;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class NetworkViewPanel extends JPanel{
private final List<JLabel> labels;
public NetworkViewPanel() {
this.setLayout(new GridLayout(2, 2, 2, 2));
this.setPreferredSize(new Dimension(400,300));
labels = new ArrayList<>();
addLabels(new String[]{ "A", "B" , "C" , "D"});
}
private void addLabels(String[] text){
for(String t: text){
JLabel label = new JLabel(t);
label.setBorder(BorderFactory.createLineBorder(Color.BLUE));
label.setHorizontalAlignment(JLabel.CENTER);
add(label);
labels.add(label);
}
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g); //draw panel as layed out by layout manager
drawLines(g);
}
private void drawLines(Graphics g) {
//draw line between centers of first and last components
int x1 = labels.get(0).getBounds().x + labels.get(0).getBounds().width /2;
int y1 = labels.get(0).getBounds().y + labels.get(0).getBounds().height /2;
int x2 = labels.get(labels.size()-1).getBounds().x + labels.get(labels.size()-1).getBounds().width/2;
int y2 = labels.get(labels.size()-1).getBounds().y + labels.get(labels.size()-1).getBounds().height/2;
g.setColor(Color.RED);
g.drawLine(x1, y1, x2, y2);
}
public static void main(String[] args) {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setLocationRelativeTo(null);
f.add(new NetworkViewPanel());
f.pack();
f.setVisible(true);
}
}