如何使用 Java 在 JTree 元件中找到節點?


要查詢 JTree 元件中的節點,請使用 getNextMatch() 方法。此處,我們嘗試查詢以 “A” 字元開頭的節點。從使用 begnRow 變數設定的以下節點開始搜尋 −

int begnRow = 0;
String prefix = "A"; TreePath treePath = tree.getNextMatch(prefix, begnRow, Position.Bias.Forward);

我們已在控制檯中顯示結果節點 −

System.out.println("Node = "+treePath);

以下是如何使用 Java 查詢 JTree 元件中的節點的示例 −

package my;
import javax.swing.JFrame;
import javax.swing.JTree;
import javax.swing.text.Position;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreePath;
public class SwingDemo {
   public static void main(String[] args) throws Exception {
      JFrame frame = new JFrame("Demo");
      DefaultMutableTreeNode node = new DefaultMutableTreeNode("Project");
      DefaultMutableTreeNode node1 = new DefaultMutableTreeNode("App");
      DefaultMutableTreeNode node2 = new DefaultMutableTreeNode("Website");
      DefaultMutableTreeNode node3 = new DefaultMutableTreeNode("WebApp");
      node.add(node1);
      node.add(node2);
      node.add(node3);
      DefaultMutableTreeNode one = new DefaultMutableTreeNode("Learning website");
      DefaultMutableTreeNode two = new DefaultMutableTreeNode("Business website");
      DefaultMutableTreeNode three = new DefaultMutableTreeNode("News publishing website");
      DefaultMutableTreeNode four = new DefaultMutableTreeNode("Android app");
      DefaultMutableTreeNode five = new DefaultMutableTreeNode("iOS app");
      DefaultMutableTreeNode six = new DefaultMutableTreeNode("Editor WebApp");
      node1.add(one);
      node1.add(two);
      node1.add(three);
      node2.add(four);
      node2.add(five);
      node3.add(six);
      JTree tree = new JTree(node);
      int begnRow = 0;
      String prefix = "A"; TreePath treePath = tree.getNextMatch(prefix, begnRow, Position.Bias.Forward); System.out.println("Node = "+treePath);
      tree.setRowHeight(25);
      frame.add(tree);
      frame.setSize(550,400);
      frame.setVisible(true);
   }
}

輸出

輸出如下。執行時,可以看到要查詢的節點 −

更新於: 30-Jul-2019

686 次瀏覽

啟動你的事業

完成課程後獲得認證

開始
廣告
© . All rights reserved.