CoreJava1/chapter12/src/circleLayout/CircleLayout.java at v11 · WisdomApple/CoreJava1 · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
package circleLayout;

import java.awt.*;

/**
 * A layout manager that lays out components along a circle.
 */
public class CircleLayout implements LayoutManager {
    private int minWidth = 0;
    private int minHeight = 0;
    private int preferredWidth = 0;
    private int preferredHeight = 0;
    private boolean sizesSet = false;
    private int maxComponentWidth = 0;
    private int maxComponentHeight = 0;

    @Override
    public void addLayoutComponent(String name, Component comp) {

    }

    @Override
    public void removeLayoutComponent(Component comp) {

    }

    @Override
    public Dimension preferredLayoutSize(Container parent) {
        setSizes(parent);
        Insets insets = parent.getInsets();
        int width = preferredWidth + insets.left + insets.right;
        int height = preferredHeight + insets.top + insets.bottom;
        return new Dimension(width, height);
    }

    @Override
    public Dimension minimumLayoutSize(Container parent) {
        setSizes(parent);
        Insets insets = parent.getInsets();
        int width = minWidth + insets.left + insets.right;
        int height = minHeight + insets.top + insets.bottom;
        return new Dimension(width, height);
    }

    @Override
    public void layoutContainer(Container parent) {
        setSizes(parent);

        // compute center of the circle

        Insets insets = parent.getInsets();
        int containerWidth = parent.getSize().width - insets.left - insets.right;
        int containerHeight = parent.getSize().height - insets.top - insets.bottom;

        int x_center = insets.left + containerWidth / 2;
        int y_center = insets.top + containerHeight / 2;

        // compute radius of the circle
        int x_radius = (containerWidth - maxComponentWidth) / 2;
        int y_radius = (containerHeight - maxComponentHeight) / 2;
        int radius = Math.min(x_radius, y_radius);

        // lay out components along the circle
        int n = parent.getComponentCount();
        for (int i = 0; i < n; i++) {
            Component component = parent.getComponent(i);
            if (component.isVisible()) {
                double angle = 2 * Math.PI * i / n;

                // center point of component
                int x = x_center + (int) (Math.cos(angle) * radius);
                int y = y_center + (int) (Math.sin(angle) * radius);

                // move component so that its center is (x, y)
                // and its size is its preferred size
                Dimension d = component.getPreferredSize();
                component.setBounds(x - d.width / 2, y - d.height / 2, d.width, d.height);
            }
        }
    }

    public void setSizes(Container parent) {
        if (sizesSet) return;
        int n = parent.getComponentCount();

        preferredWidth = 0;
        preferredHeight = 0;
        minWidth = 0;
        minHeight = 0;
        maxComponentWidth = 0;
        maxComponentHeight = 0;


        // compute the maximum component widths and heights
        // and set the preferred size to the sum of the component sizes.
        for (int i = 0; i < n; i++) {
            Component component = parent.getComponent(i);
            if (component.isVisible()) {
                Dimension dimension = component.getPreferredSize();
                maxComponentWidth = Math.max(maxComponentWidth, dimension.width);
                maxComponentHeight = Math.max(maxComponentHeight, dimension.height);
                preferredWidth += dimension.width;
                preferredHeight += dimension.height;
            }
        }
        minWidth = preferredWidth / 2;
        minHeight = preferredHeight / 2;
        sizesSet = true;
    }
}