Java将矩形添加到ArrayList,然后绘制它们
我真的需要你们的帮助。 我尝试将矩形添加到ArrayList中,然后在列表中循环绘制所有矩形。我不确定我是否使用了正确的方法,但这是我到目前为止的代码 编辑:代码没有绘制我添加到ArrayList中的矩形。我甚至不知道它们是以正确的方式添加的,还是通过for循环以正确的方式访问的 在测试程序中Java将矩形添加到ArrayList,然后绘制它们,java,swing,arraylist,Java,Swing,Arraylist,我真的需要你们的帮助。 我尝试将矩形添加到ArrayList中,然后在列表中循环绘制所有矩形。我不确定我是否使用了正确的方法,但这是我到目前为止的代码 编辑:代码没有绘制我添加到ArrayList中的矩形。我甚至不知道它们是以正确的方式添加的,还是通过for循环以正确的方式访问的 在测试程序中 import java.awt.BorderLayout; import java.awt.Graphics; import java.util.ArrayList; import javax.swing
import java.awt.BorderLayout;
import java.awt.Graphics;
import java.util.ArrayList;
import javax.swing.JFrame;
public class TestProgram extends JFrame {
private ShapeRectangle rectangle;
public ArrayList<Shapes> list = new ArrayList<Shapes>();
public TestProgram(String title) {
super(title);
setLayout(new BorderLayout());
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLocationRelativeTo(null);
initComponents();
setSize(500, 700);
setVisible(true);
}
private void initComponents() {
rectangle = new ShapeRectangle();
add(rectangle, BorderLayout.CENTER);
list.add(rectangle);
Graphics g = getGraphics();
for (int i = 0; i < list.size(); i++) {
rectangle.draw(g);
}
}
public static void main(String args[]) {
new TestProgram("Drawing program");
}
}
类内形状:
import java.awt.Graphics;
import javax.swing.JPanel;
public abstract class Shapes extends JPanel {
abstract public void draw(Graphics g);
}不要做
形状aJPanel
。同时取出其paintComponent
方法
取而代之的是一个JPanel
类,它是主绘图面。将列表
保留在课堂中。迭代该类的paintComponent
方法中的列表,调用每个Shapes
的draw方法
class DrawingPanel extends JPanel {
List<Shapes> shapes;
// add shapes
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (Shapes shape: shapes) {
shape.draw(g);
}
}
}
请参见a不要制作形状
aJPanel
。同时取出其paintComponent
方法
取而代之的是一个JPanel
类,它是主绘图面。将列表
保留在课堂中。迭代该类的paintComponent
方法中的列表,调用每个Shapes
的draw方法
class DrawingPanel extends JPanel {
List<Shapes> shapes;
// add shapes
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (Shapes shape: shapes) {
shape.draw(g);
}
}
}
请参见a这很糟糕,您要么想将其添加为具有绝对定位的组件,要么想绘制它,请选择一个
this.add(rectangle, BorderLayout.CENTER); // Add as component of the panel.
list.add(rectangle); // Add as method of drawing on the panel.
后者将更好地工作,因为您正在绘图。如果需要拖放,请将其作为子对象添加,但将图形添加到子对象
更改矩形的坐标和大小后,可以在JFrame上调用repaint()
,以更新图形
拉丝
形状
这是不好的,您要么要将其添加为具有绝对定位的组件,要么要绘制它,请选择一个
this.add(rectangle, BorderLayout.CENTER); // Add as component of the panel.
list.add(rectangle); // Add as method of drawing on the panel.
后者将更好地工作,因为您正在绘图。如果需要拖放,请将其作为子对象添加,但将图形添加到子对象
更改矩形的坐标和大小后,可以在JFrame上调用repaint()
,以更新图形
拉丝
形状
首先看一下
2D图形API定义了形状
API,其中包括矩形
类
例如
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestRectangles {
public static void main(String[] args) {
new TestRectangles();
}
public TestRectangles() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private List<Rectangle> rectangles;
public TestPane() {
rectangles = new ArrayList<>(25);
Random ran = new Random();
for (int index = 0; index < 10; index++) {
int x = ran.nextInt(200 - 10);
int y = ran.nextInt(200 - 10);
int width = ran.nextInt(200 - x);
int height = ran.nextInt(200 - y);
rectangles.add(new Rectangle(
x,
y,
width,
height));
}
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
for (Rectangle rect : rectangles) {
g2d.draw(rect);
}
g2d.dispose();
}
}
}
导入java.awt.Dimension;
导入java.awt.EventQueue;
导入java.awt.Graphics;
导入java.awt.Graphics2D;
导入java.awt.Rectangle;
导入java.util.ArrayList;
导入java.util.List;
导入java.util.Random;
导入javax.swing.JFrame;
导入javax.swing.JPanel;
导入javax.swing.UIManager;
导入javax.swing.UnsupportedLookAndFeelException;
公共类测试矩形{
公共静态void main(字符串[]args){
新的test矩形();
}
公共测试矩形(){
invokeLater(新的Runnable(){
@凌驾
公开募捐{
试一试{
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
}catch(ClassNotFoundException |实例化Exception | IllegalacessException |不支持ookandfeelException ex){
例如printStackTrace();
}
JFrame=新JFrame(“测试”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(newtestpane());
frame.pack();
frame.setLocationRelativeTo(空);
frame.setVisible(true);
}
});
}
公共类TestPane扩展了JPanel{
私有列表矩形;
公共测试窗格(){
矩形=新阵列列表(25);
Random ran=新的Random();
对于(int-index=0;index<10;index++){
int x=ran.nextInt(200-10);
int y=ran.nextInt(200-10);
int width=ran.nextInt(200-x);
int height=ran.nextInt(200-y);
矩形。添加(新矩形)(
x,,
Y
宽度,
身高),;
}
}
@凌驾
公共维度getPreferredSize(){
返回新维度(200200);
}
@凌驾
受保护组件(图形g){
超级组件(g);
Graphics2D g2d=(Graphics2D)g.create();
用于(矩形:矩形){
g2d.draw(rect);
}
g2d.dispose();
}
}
}
首先看一下
2D图形API定义了形状
API,其中包括矩形
类
例如
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestRectangles {
public static void main(String[] args) {
new TestRectangles();
}
public TestRectangles() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private List<Rectangle> rectangles;
public TestPane() {
rectangles = new ArrayList<>(25);
Random ran = new Random();
for (int index = 0; index < 10; index++) {
int x = ran.nextInt(200 - 10);
int y = ran.nextInt(200 - 10);
int width = ran.nextInt(200 - x);
int height = ran.nextInt(200 - y);
rectangles.add(new Rectangle(
x,
y,
width,
height));
}
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
for (Rectangle rect : rectangles) {
g2d.draw(rect);
}
g2d.dispose();
}
}
}
导入java.awt.Dimension;
导入java.awt.EventQueue;
导入java.awt.Graphics;
导入java.awt.Graphics2D;
导入java.awt.Rectangle;
导入java.util.ArrayList;
导入java.util.List;
导入java.util.Random;
导入javax.swing.JFrame;
导入javax.swing.JPanel;
导入javax.swing.UIManager;
导入javax.swing.UnsupportedLookAndFeelException;
公共类测试矩形{
公共静态void main(字符串[]args){
新的test矩形();
}
公共测试矩形(){
invokeLater(新的Runnable(){
@凌驾
公开募捐{
试一试{
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
}catch(ClassNotFoundException |实例化Exception | IllegalacessException |不支持ookandfeelException ex){
例如printStackTrace();
}
JFrame=新JFrame(“测试”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(newtestpane());
frame.pack();
frame.setLocationRelativeTo(空);
frame.setVisible(真)
import java.awt.Graphics;
public abstract class Shape {
private int x;
private int y;
private int width;
private int height;
public Shape() {
this(0, 0, 1, 1);
}
public Shape(int x, int y, int width, int height) {
this.x = x;
this.y = y;
this.width = width;
this.height = height;
}
public abstract void draw(Graphics g);
public int getX() {
return x;
}
public void setX(int x) {
this.x = x;
}
public int getY() {
return y;
}
public void setY(int y) {
this.y = y;
}
public int getWidth() {
return width;
}
public void setWidth(int width) {
this.width = width;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
}
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestRectangles {
public static void main(String[] args) {
new TestRectangles();
}
public TestRectangles() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private List<Rectangle> rectangles;
public TestPane() {
rectangles = new ArrayList<>(25);
Random ran = new Random();
for (int index = 0; index < 10; index++) {
int x = ran.nextInt(200 - 10);
int y = ran.nextInt(200 - 10);
int width = ran.nextInt(200 - x);
int height = ran.nextInt(200 - y);
rectangles.add(new Rectangle(
x,
y,
width,
height));
}
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
for (Rectangle rect : rectangles) {
g2d.draw(rect);
}
g2d.dispose();
}
}
}