如何獲取JScrollPane內部（可更改）組件的完整大小？

Question

我的代碼是這樣的：

JFrame frame = new JFrame(); 

JPanel panel = new JPanel(); 

JTextPane text = new JTextPane(); 
text.setPreferredSize(new Dimension(200,260)); 
text.setContentType("text/html"); 
text.setEditable(false); 
text.setText("some random thing makes this pane bigger than its perferred size"); 

JScrollPane scroll = new JScrollPane(text); 

panel.add(scroll); 

frame.add(panel); 
frame.setVisible(true); 
frame.pack(); 
frame.validate(); 

我的問題是我不知道如何讓JTextPane（在文本這裏）的實際大小。我已經嘗試了所有getSizes & getVisibleRects，scroll.getViewport().getViewSize() ......但他們都返回[200,260]。有人可以幫我解決這個問題嗎？我非常感謝您提供的任何幫助。

編輯：我發現了問題：進行了驗證框架前被處決我getSizes請求。 我可運行測試代碼：

import java.awt.Dimension; 

import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.JScrollPane; 
import javax.swing.JTextPane; 

public class Abcd { 

public static void main(String[] args) { 
    // TODO Auto-generated method stub 
    JFrame frame = new JFrame(); 

    JPanel panel = new JPanel(); 

    JTextPane text = new JTextPane(); 
    text.setPreferredSize(new Dimension(150,126)); 
    text.setContentType("text/html"); 
    text.setEditable(false); 

    //Alicia Vikander's photo. She's cute anw. 
    String tmp = "<a href=\"https://upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Alicia_Vikander.jpg/220px-Alicia_Vikander.jpg\"><img src=\"https://upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Alicia_Vikander.jpg/220px-Alicia_Vikander.jpg\"/></a>"; 
    //text.setText("asdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sfasdf fssdfsdf sfdsdf sd sdf sf"); 
    text.setText(tmp); 
    JScrollPane scroll = new JScrollPane(text); 
    scroll.setPreferredSize(new Dimension(150,126)); 

    panel.add(scroll); 

    frame.add(panel); 
    frame.setVisible(true); 
    frame.pack(); 
    frame.validate(); 
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

    for (double i = 0; i < 1000; i = i + 0.0001){ 
     System.out.print(text.getHeight()+"\n");    
     if (text.getHeight()!=123){ //3 pixels for the scrollpane's border i guessed 
      System.out.print("i = "+i+", height = "+text.getHeight()); 
      break; 
     } 
    } 
} 

在我的電腦i大約是50 - 100。因此，我的新的問題是：是否有反正我可以，只要我可以，但仍然確保幀被驗證得到realsize ？ 非常感謝。

Answer 1

我強烈建議你開始使用不同的Layout managers。

如果我tweek你的代碼中：

JFrame frame = new JFrame(); 

final JTextPane text = new JTextPane(); 
text.setContentType("text/html"); 
text.setEditable(false); 
text.setText("some random thing makes this pane bigger than its perferred size"); 

final JScrollPane scroll = new JScrollPane(text); 
scroll.addComponentListener(new ComponentAdapter() { 
     @Override 
     public void componentResized(ComponentEvent e) { 
      System.out.println("Size of JScrollPane is: " + scroll.getSize()); 
      System.out.println("Size of JTextPane is: " + text.getSize()); 
     } 
}); 

frame.setLayout(new BorderLayout()); 
frame.add(scroll,BorderLayout.CENTER); 
frame.pack(); 
frame.setVisible(true); 

我們將有滾動元件的尺寸調用其scroll.getSize()和文本組件調用它text.getSize()