JLabel图像阵列 [英] JLabel images array
问题描述
我正在尝试将相同的jlabel存储图像两次加载到gridlayout面板中，但是不是创建图像的两个实例，而是仅显示一次图像然后移动。
I am trying to load the same jlabel stored image twice into a gridlayout panel, however instead of creating two instances of the image, the image is only displayed once then moved.
如何将件数组中相同的JLabel位置存储到boardLabels数组中的多个JLabel中。
How can I store the same JLabel position in the pieces array into more than one JLabel in the boardLabels array.
谢谢：）
public static JPanel boardPanel = new JPanel(new GridLayout(4, 0));
public static JLabel pieces[] = new JLabel[2];
private static JLabel[] boardLabels = new JLabel[4];
public MainFrame() {
pieces[0] = new JLabel(new ImageIcon(System.getProperty("user.dir") + "/images/piece1.png"));
pieces[1] = new JLabel(new ImageIcon(System.getProperty("user.dir") + "/images/piece2.png"));
this.add(boardPanel);
displayGUIboard();
}
public static void displayGUIboard() {
//ERROR - the label in pieces[0] is not copied into both boardLabels [0] and [1]
boardLabels[0] = pieces[0];
boardLabels[1] = pieces[0];
boardPanel.add(boardLabels[0]);
boardPanel.add(boardLabels[1]);
}
public static void main(String[] args) {
MainFrame frame = new MainFrame();
frame.setVisible(true);
frame.setSize(600, 600);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
此作品
boardLabels[0] = new JLabel(pieces[1]);
boardLabels[1] = new JLabel(pieces[1]);
使用ImageIcons时，但我想避免这种情况，因为要更新电路板我将不得不删除重新加载JLabels。我更愿意只更新已经加载的标签。
when using ImageIcons, but I want to avoid this since to update the board I will have to remove then reload the JLabels. I would prefer to just update the already loaded labels.
编辑
我之前试过这个但是它抛出一个空指针异常......
edit I tried this before but it throws a null pointer exception...
boardLabels[0].setIcon(pieces[1]);
boardLabels[1].setIcon(pieces[1]);
boardPanel.add(boardLabels[0]);
boardPanel.add(boardLabels[1]);
推荐答案
不要这样做，因为你无法添加同一个组件不止一次到可视化容器。最好使用多个JLabel，但让它们使用相同的 ImageIcon 。 ImageIcons可以轻松使用多次：
Don't do this since you can't add the same component more than once to a visualized container. Better to use multiple JLabels but have them use the same ImageIcon. ImageIcons can be used more than once with ease:
public MainFrame() {
pieceIcon[0] = new ImageIcon(System.getProperty("user.dir") +
"/images/piece1.png");
pieceIcon[1] = new ImageIcon(System.getProperty("user.dir") +
"/images/piece2.png");
this.add(boardPanel);
displayGUIboard();
}
public void displayGUIboard() {
boardPanel.add(new JLabel(pieceIcon[0]);
boardPanel.add(new JLabel(pieceIcon[0]);
}
暂且不说：注意你的变量没有应该是静态的。
As an aside: note that none of your variables should be static.
编辑关于你最近的编辑：
这是有效的
This works
boardLabels[0] = new JLabel(pieces[1]);
boardLabels[1] = new JLabel(pieces[1]);
使用ImageIcons时，但我想避免这种情况，因为要更新电路板我必须删除然后重新加载JLabel。我宁愿只更新已加载的标签。
when using ImageIcons, but I want to avoid this since to update the board I will have to remove then reload the JLabels. I would prefer to just update the already loaded labels."
解决方案
不，你不需要更改JLabels将JLabel保留在原来的位置，只需使用JLabel setIcon（...）方法交换它们所持有的图标。
Solution
No you don't have to change JLabels at all. Keep your JLabels where they are, but simply swap the icons that they hold using the JLabel setIcon(...) method.
修改
此外，请勿将变量与对象混淆。即使您创建了一堆JLabel变量，如果它们都引用相同的JLabel对象，您仍然无法将多个 JLabel对象多次添加到容器中。
Edit
Also, don't confuse variables with objects. Even if you create a bunch of JLabel variables, if they all refer to the same JLabel object, you still can't add a JLabel object more than once to a container.
编辑您声明：
代码是显示功能的一部分对于一场比赛。整数数组将表示被解释的板（但不在上面的代码中），并且正确的Jlabel图像将被放置在gridlayout面板中以显示板的gui。我已经让显示代码工作正常，但在我当前的版本中它从板上删除jlabel然后创建新的JLabel（片...）...但我希望它从整数数组更新自己而不是删除标签，读取数组，然后重新创建标签。
The code is a part of the display function for a game. An array of integers will represent the board which is interpreted (but not in the above code) and the correct Jlabel images will be placed into a gridlayout panel to display the gui of the board. I have gotten the display code to work fine, but in my current version it removes the jlabels from the board then creates new JLabels(piece...)... but i would prefer it to update itself from the integer array rather than removing the labels, reading the array, then recreating the labels.
因此，创建一个使用GridLayout并使用不变的JLabel填充它的JPanel。然后，只需根据int数组保存的值更改JLabels所拥有的图标。您可以创建一种简化和自动化此过程的方法。
So create a JPanel that uses GridLayout and fill it with unchanging JLabels. Then simply change the icons held by the JLabels based on the values held by the int array. You could create a method that simplifies and automates this process.
编辑关于：
编辑我之前试过这个但是它抛出一个空指针异常。
edit I tried this before but it throws a null pointer exception.
然后解决这个问题任何NPE。找出抛出NPE的行，检查行上的变量，至少有一行为null，然后修复它以便在尝试使用它之前初始化变量。
Then solve this as you would any NPE. Find out which line throws the NPE, check the variables on the line, at least one is null, and then fix it so that you initialize the variable before trying to use it.
编辑
例如：
Edit
for example:
import java.awt.Color;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.image.BufferedImage;
import javax.swing.*;
@SuppressWarnings("serial")
public class GridExample extends JPanel {
public static final int[][] MAP = {
{1, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2},
{1, 1, 0, 0, 2, 2, 2, 2, 2, 2, 2},
{1, 1, 1, 0, 2, 2, 2, 2, 2, 2, 2},
{1, 1, 1, 0, 0, 2, 2, 2, 2, 2, 2},
{1, 1, 1, 1, 0, 2, 2, 2, 2, 2, 2},
{1, 1, 1, 0, 0, 0, 2, 2, 2, 2, 2},
{1, 1, 0, 0, 0, 2, 2, 2, 2, 2, 2},
{1, 1, 1, 0, 0, 0, 2, 2, 2, 2, 2},
{1, 1, 1, 1, 1, 0, 0, 0, 0, 2, 2},
{1, 1, 1, 1, 1, 0, 0, 0, 2, 2, 2},
{1, 1, 1, 1, 1, 1, 0, 0, 0, 2, 2}
};
public static final Color[] COLORS = {};
private JLabel[][] labelGrid = new JLabel[MAP.length][MAP[0].length];
public GridExample() {
setLayout(new GridLayout(MAP.length, MAP[0].length));
for (int r = 0; r < labelGrid.length; r++) {
for (int c = 0; c < labelGrid[r].length; c++) {
labelGrid[r][c] = new JLabel();
labelGrid[r][c].setIcon(Ground.getGround(MAP[r][c]).getIcon());
add(labelGrid[r][c]);
}
}
}
private static void createAndShowGui() {
GridExample mainPanel = new GridExample();
JFrame frame = new JFrame("GridExample");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
enum Ground {
DIRT(0, new Color(205,133, 63)), GRASS(1, new Color(0, 107, 60)),
WATER(2, new Color(29, 172, 214));
private int value;
private Color color;
private Icon icon;
private Ground(int value, Color color) {
this.value = value;
this.color = color;
icon = createIcon(color);
}
private Icon createIcon(Color color) {
int width = 24; // how to use const in enum?
BufferedImage img = new BufferedImage(width, width, BufferedImage.TYPE_INT_ARGB);
Graphics g = img.getGraphics();
g.setColor(color);
g.fillRect(0, 0, width, width);
g.dispose();
return new ImageIcon(img);
}
public int getValue() {
return value;
}
public Color getColor() {
return color;
}
public Icon getIcon() {
return icon;
}
public static Ground getGround(int value) {
for (Ground ground : Ground.values()) {
if (ground.getValue() == value) {
return ground;
}
}
return null;
}
}
显示GUI网格：< br>
Which shows a GUI grid:
这篇关于JLabel图像阵列的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
