我们能在 Java 中用预定义选择设置 JOptionPane 吗?
java 8object oriented programmingprogramming
对于预定义选择，请使用 setSelectedIndex() 方法，其中您需要先设置要显示的项的索引。
假设以下是带有元素 − 的 aComboBox
Object[] sports = { "Football", "Cricket", "Squash", "Baseball", "Fencing", "Volleyball", "Basketball" };
JComboBox comboBox = new JComboBox(sports);
现在，用项的索引设置初始选择 −
comboBox.setSelectedIndex(3);
以下是在 Java 中设置带有预定义选择的 JOptionPane 的示例 −
示例
package my;
import java.awt.GridBagLayout;
import javax.swing.JComboBox;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class SwingDemo {
public static void main(String[] args) throws Exception {
JPanel panel = new JPanel(new GridBagLayout());
Object[] sports = { "Football", "Cricket", "Squash", "Baseball", "Fencing", "Volleyball", "Basketball" };
JComboBox comboBox = new JComboBox(sports);
// 初始选择
comboBox.setSelectedIndex(3);
JOptionPane.showMessageDialog(null, comboBox, "Fav Sports",
JOptionPane.QUESTION_MESSAGE);
panel.add(comboBox);
}
}
输出
