import javax.swing.JFrame;
import javax.swing.SwingUtilities;
>>>import java.awt.GridBagLayout;
import java.awt.GridBagConstraints;
import javax.swing.JButton;
import javax.swing.BorderFactory;
public class GridBagLayout {
public static void createWindow(){
JFrame aWin = new JFrame("Title");
aWin.setBounds(0,0,200,200);
aWin.setVisible(true);
GridBagLayout gridBag = new GridBagLayout();
GridBagConstraints constraints = new GridBagConstraints();
>>>aWin.getContentPane().setLayout(gridBag);
constraints.weightx = constraints.weighty = 10.0;
constraints.fill = GridBagConstraints.BOTH;
addButton(" Press ",constraints,gridBag,aWin);
constraints.gridwidth=GridBagConstraints.REMAINDER;
}
static void addButton(String label,GridBagConstraints constraints,GridBagLayout layout,JFrame window){
JButton button = new JButton(label);
button.setBorder(BorderFactory.createEtchedBorder());
>>>layout.setConstraints(button,constraints);
window.getContentPane().add(button);
}
public static void main(String[] args){
SwingUtilities.invokeLater(new Runnable(){
public void run(){
createWindow();
}
});
}
}
標有>>>的行被Eclipse IDE標記爲錯誤。
import java.awt.GridBagLayout;
的錯誤表明與同一文件中的類型可能存在衝突
aWin.getContentPane().setLayout(gridBag);
的錯誤表明GridBagLayout無法應用,儘管當我嘗試使用FlowLayout時,它沒有問題。
layout.setConstraints(button,constraints);
的錯誤表明該方法未定義。
這個錯誤的原因是什麼?請幫我解決它。GridBagLayout被標記爲錯誤