---
category: swing
folder: CurveLayout
title: LayoutManagerを拡張して曲線上にコンポーネントを配置
tags: [LayoutManager, FlowLayout, JPanel]
author: aterai
pubdate: 2011-06-27T14:12:48+09:00
description: LayoutManagerを拡張して曲線上にコンポーネントを配置します。
image: https://lh4.googleusercontent.com/-Rww2mulIVEI/TggO-rFh_2I/AAAAAAAAA98/R3ZVsfyu3IU/s800/CurveLayout.png
hreflang:
    href: https://java-swing-tips.blogspot.com/2012/05/creating-custom-layout-manager.html
    lang: en
---
* 概要 [#summary]
`LayoutManager`を拡張して曲線上にコンポーネントを配置します。

#download(https://lh4.googleusercontent.com/-Rww2mulIVEI/TggO-rFh_2I/AAAAAAAAA98/R3ZVsfyu3IU/s800/CurveLayout.png)

* サンプルコード [#sourcecode]
#code(link){{
final double A2 = 4.0;
panel2.setLayout(new FlowLayout() {
  @Override public void layoutContainer(Container target) {
    synchronized(target.getTreeLock()) {
      Insets insets = target.getInsets();
      Insets i = target.getInsets();
      int nmembers  = target.getComponentCount();
      if (nmembers <= 0) {
        return;
      }
      int vgap = getVgap();
      int hgap = getHgap();
      int rowh = (target.getHeight() - (insets.top + insets.bottom + vgap * 2)) / nmembers;
      int x = insets.left + hgap;
      int y = insets.top  + vgap;
      int rowh = (target.getHeight() - (i.top + i.bottom + vgap * 2)) / nmembers;
      int x = i.left + hgap;
      int y = i.top  + vgap;
      for (int i = 0; i < nmembers; i++) {
        Component m = target.getComponent(i);
        if (m.isVisible()) {
          Dimension d = m.getPreferredSize();
          m.setSize(d.width, d.height);
          m.setLocation(x, y);
          y += (vgap + Math.min(rowh, d.height));
          x = (int) (A2 * Math.sqrt(y));
        }
      }
    }
  }
});
}}

* 解説 [#explanation]
- 左: `FlowLayout(LEFT)`
-- `new FlowLayout(FlowLayout.LEFT)`を設定した`JPanel`にコンポーネントを配置
- 右: `y=Math.pow(x/4.0,2.0)`
-- `FlowLayout#layoutContainer(...)`をオーバーライドし、二次曲線の上にコンポーネントを配置するレイアウトを`JPanel`に設定

* 参考リンク [#reference]
- [https://docs.oracle.com/javase/jp/8/docs/api/java/awt/FlowLayout.html#layoutContainer-java.awt.Container- FlowLayout#layoutContainer(Container) (Java Platform SE 8)]

* コメント [#comment]
#comment
#comment