为组件所在的位置仍然存在空白。
是的，GridLayout不是那么聪明。它仅使用组件总数
来确定行/列的数量。
有没有快速简便的方法来做到这一点？
我将创建一个自定义布局管理器。只需复制GridLayout代码并进行
一些更改。基本更改为：
覆盖ncomponents变量。不仅需要使用面板上的组件数量，还需要循环遍历所有组件并计算可见组件。
在布局代码中，您需要添加一个if (visible)检查。
Edit:
import java.awt.*;import java.awt.event.*;import javax.swing.*;import javax.swing.border.*;public class InvisibleGridLayout implements LayoutManager, java.io.Serializable{ int hgap; int vgap; int rows; int cols; public InvisibleGridLayout() { this(1, 0, 0, 0); } public InvisibleGridLayout(int rows, int cols) { this(rows, cols, 0, 0); } public InvisibleGridLayout(int rows, int cols, int hgap, int vgap) { if ((rows == 0) && (cols == 0)) { throw new IllegalArgumentException("rows and cols cannot both be zero"); } this.rows = rows; this.cols = cols; this.hgap = hgap; this.vgap = vgap; } public int getRows() { return rows; } public void setRows(int rows) { if ((rows == 0) && (this.cols == 0)) { throw new IllegalArgumentException("rows and cols cannot both be zero"); } this.rows = rows; } public int getColumns() { return cols; } public void setColumns(int cols) { if ((cols == 0) && (this.rows == 0)) { throw new IllegalArgumentException("rows and cols cannot both be zero"); } this.cols = cols; } public int getHgap() { return hgap; } public void setHgap(int hgap) { this.hgap = hgap; } public int getVgap() { return vgap; } public void setVgap(int vgap) { this.vgap = vgap; } public void addLayoutComponent(String name, Component comp) { } public void removeLayoutComponent(Component comp) { } public Dimension preferredLayoutSize(Container parent) { synchronized (parent.getTreeLock()) { Insets insets = parent.getInsets();// int ncomponents = parent.getComponentCount(); int ncomponents = getVisibleComponents(parent); int nrows = rows; int ncols = cols; if (nrows > 0) { ncols = (ncomponents + nrows - 1) / nrows; } else { nrows = (ncomponents + ncols - 1) / ncols; } int w = 0; int h = 0;// for (int i = 0 ; i < ncomponents ; i++) { for (int i = 0 ; i < parent.getComponentCount(); i++) { Component comp = parent.getComponent(i); if (!comp.isVisible()) continue; // added Dimension d = comp.getPreferredSize(); if (w < d.width) { w = d.width; } if (h < d.height) { h = d.height; } } Dimension d = new Dimension(insets.left + insets.right + ncols*w + (ncols-1)*hgap, insets.top + insets.bottom + nrows*h + (nrows-1)*vgap); return d; } } public Dimension minimumLayoutSize(Container parent) { synchronized (parent.getTreeLock()) { Insets insets = parent.getInsets();// int ncomponents = parent.getComponentCount(); int ncomponents = getVisibleComponents(parent); int nrows = rows; int ncols = cols; if (nrows > 0) { ncols = (ncomponents + nrows - 1) / nrows; } else { nrows = (ncomponents + ncols - 1) / ncols; } int w = 0; int h = 0;// for (int i = 0 ; i < ncomponents ; i++) { for (int i = 0 ; i < parent.getComponentCount(); i++) { Component comp = parent.getComponent(i); if (!comp.isVisible()) continue; // added Dimension d = comp.getMinimumSize(); if (w < d.width) { w = d.width; } if (h < d.height) { h = d.height; } } Dimension d = new Dimension(insets.left + insets.right + ncols*w + (ncols-1)*hgap, insets.top + insets.bottom + nrows*h + (nrows-1)*vgap); return d; } } public void layoutContainer(Container parent) { synchronized (parent.getTreeLock()) { Insets insets = parent.getInsets();// int ncomponents = parent.getComponentCount(); int ncomponents = getVisibleComponents(parent); int nrows = rows; int ncols = cols; boolean ltr = parent.getComponentOrientation().isLeftToRight(); if (ncomponents == 0) { return; } if (nrows > 0) { ncols = (ncomponents + nrows - 1) / nrows; } else { nrows = (ncomponents + ncols - 1) / ncols; }// int w = parent.width - (insets.left + insets.right);// int h = parent.height - (insets.top + insets.bottom); int w = parent.getSize().width - (insets.left + insets.right); int h = parent.getSize().height - (insets.top + insets.bottom); w = (w - (ncols - 1) * hgap) / ncols; h = (h - (nrows - 1) * vgap) / nrows; int i = 0; if (ltr) { for (int r = 0, y = insets.top ; r < nrows ; r++, y += h + vgap) { int c = 0; int x = insets.left; while (c < ncols) { if (i >= parent.getComponentCount()) break; Component component = parent.getComponent(i); if (component.isVisible()) { parent.getComponent(i).setBounds(x, y, w, h); c++; x += w + hgap; } i++; } } } }} private int getVisibleComponents(Container parent) { int visible = 0; for (Component c: parent.getComponents()) { if (c.isVisible()) visible++; } return visible; } public String toString() { return getClass().getName() + "[hgap=" + hgap + ",vgap=" + vgap + ",rows=" + rows + ",cols=" + cols + "]"; } public static void main(String[] args) { final JPanel innerPane = new JPanel(); JScrollPane scr = new JScrollPane(innerPane); innerPane.setLayout(new InvisibleGridLayout(0, 3)); for (int i = 0; i < 30; i++) { JPanel ret = new JPanel(); JLabel lbl = new JLabel("This is pane " + i); ret.add(lbl); ret.setBorder(BorderFactory.createBevelBorder(BevelBorder.RAISED)); ret.setBackground(Color.gray); innerPane.add(ret); } Jframe frame = new Jframe(); frame.setDefaultCloseOperation(Jframe.EXIT_ON_CLOSE); frame.add(scr); frame.setBounds(400, 0, 400, 700); frame.setVisible(true); javax.swing.Timer timer = new javax.swing.Timer(2000, new ActionListener() { public void actionPerformed(ActionEvent e) { for (int i = 0; i < 30; i++) { if (i%2==0) innerPane.getComponent(i).setVisible(false); } } }); timer.setRepeats(false); timer.start(); }}
