如何获得文本在 JTable 单元格中的确切 space？

Question

我在 JScrollPane 中有一行 header，我应该根据文本的最大宽度设置其宽度。我设法做到了，但我必须在对 setPreferredScrollableViewportSize 的调用中添加 1 才能显示全文。我测量错了吗？或者这个数量是固定的？

这是主要的class。

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.WindowConstants;

public class Example {
    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable(){
            @Override
            public void run(){
                JTable table = new JTable(5, 3);
                table.setPreferredScrollableViewportSize(table.getPreferredSize());
                HeaderColumn ch = new HeaderColumn(5, 1);
                JFrame frame = new JFrame();
                JScrollPane sp = new JScrollPane(table);
                sp.setRowHeaderView(ch);
                frame.add(sp);
                frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
                frame.pack();
                frame.setVisible(true);
                ch.adjustSize();
            }
        });
    }
}

这是headerclass。请看adjustSize().

import java.awt.Component;
import java.awt.Dimension;
import java.awt.FontMetrics;
import javax.swing.BorderFactory;
import javax.swing.JTable;
import javax.swing.event.TableColumnModelEvent;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableColumn;


public class HeaderColumn extends JTable{
    private final int INSET = 2;

    public HeaderColumn(int r, int c){
        super(r,c);
    }


    @Override
    public void columnAdded(TableColumnModelEvent e){
        DefaultTableModel m = (DefaultTableModel)getModel();
        int rowCount = m.getRowCount();
        for(int i = 0; i < rowCount; i++){
            m.setValueAt("#" + Integer.toString(i+1), i, 0);
        }
        TableColumn tc = getColumnModel().getColumn(e.getToIndex());
        tc.setCellRenderer(new DefaultTableCellRenderer(){
            @Override
            public Component getTableCellRendererComponent(
                JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column)
           {
                setText((value == null) ? "" : value.toString());
                setBorder(BorderFactory.createEmptyBorder(0, INSET, 0, INSET));
                return this;
           }
        });
    }

    public void adjustSize(){
        FontMetrics fm = getGraphics().getFontMetrics(getTableHeader().getFont());
        int maxTextWidth = 0;
        DefaultTableModel m = (DefaultTableModel)getModel();
        int rowCount = m.getRowCount();
        for(int i = 0; i < rowCount; i ++){
            int width = fm.stringWidth(m.getValueAt(i, 0).toString());
            if(width > maxTextWidth){
                maxTextWidth = width;
            }
        }        
        setPreferredScrollableViewportSize(new Dimension(maxTextWidth+INSET*2+1, 0));
    }  
}

Answer 1

I managed to do so but I have to add 1 in my call to setPreferredScrollableViewportSize in order to display the full text. Did I get the measurement wrong? Or is this quantity fixed?

我认为您需要包括从 table 返回的 getIntercellSpacing() 值。

查看 Table Column Adjuster 了解更多信息和确定列宽的示例代码。

如何获得文本在 JTable 单元格中的确切 space？

How to get the exact space that text takes inside a cell of a JTable?

java

swing

jtable

jscrollpane

fontmetrics