我想获得有效的屏幕尺寸。即:没有任务栏的屏幕大小(或 Linux/Mac 上的等价物)。
我目前正在使用...
component.getGraphicsConfiguration().getBounds()
...并根据操作系统减去默认任务栏大小,但我想要一种即使用户调整/移动任务栏也能工作的方法。
GraphicsEnvironment 有一个方法,它返回最大可用大小,计算所有任务栏等,无论它们在哪里对齐:
GraphicsEnvironment.getLocalGraphicsEnvironment().getMaximumWindowBounds()
注意:在多显示器系统上,getMaximumWindowBounds()
返回整个显示区域的边界。要获得单个显示器的可用边界,请使用GraphicsConfiguration.getBounds()
和Toolkit.getScreenInsets()
,如其他答案所示。
这可以确定没有任务栏的屏幕大小(以像素为单位)
//size of the screen
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
//height of the task bar
Insets scnMax = Toolkit.getDefaultToolkit().getScreenInsets(getGraphicsConfiguration());
int taskBarSize = scnMax.bottom;
//available size of the screen
setLocation(screenSize.width - getWidth(), screenSize.height - taskBarSize - getHeight());
编辑
有人可以在 Xx_nix 和 Mac OSX 上运行此代码并检查 JDialog 是否真的放在右下角?
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.UIManager.LookAndFeelInfo;
public class NotificationPopup {
private static final long serialVersionUID = 1L;
private LinearGradientPaint lpg;
private JDialog dialog = new JDialog();
private BackgroundPanel panel = new BackgroundPanel();
public NotificationPopup() {
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
Insets scnMax = Toolkit.getDefaultToolkit().
getScreenInsets(dialog.getGraphicsConfiguration());
int taskBarSize = scnMax.bottom;
panel.setLayout(new GridBagLayout());
GridBagConstraints constraints = new GridBagConstraints();
constraints.gridx = 0;
constraints.gridy = 0;
constraints.weightx = 1.0f;
constraints.weighty = 1.0f;
constraints.insets = new Insets(5, 5, 5, 5);
constraints.fill = GridBagConstraints.BOTH;
JLabel l = new JLabel("You have got 2 new Messages.");
panel.add(l, constraints);
constraints.gridx++;
constraints.weightx = 0f;
constraints.weighty = 0f;
constraints.fill = GridBagConstraints.NONE;
constraints.anchor = GridBagConstraints.NORTH;
JButton b = new JButton(new AbstractAction("x") {
private static final long serialVersionUID = 1L;
@Override
public void actionPerformed(final ActionEvent e) {
dialog.dispose();
}
});
b.setOpaque(false);
b.setMargin(new Insets(1, 4, 1, 4));
b.setFocusable(false);
panel.add(b, constraints);
dialog.setUndecorated(true);
dialog.setSize(300, 100);
dialog.setLocation(screenSize.width - dialog.getWidth(),
screenSize.height - taskBarSize - dialog.getHeight());
lpg = new LinearGradientPaint(0, 0, 0, dialog.getHeight() / 2,
new float[]{0f, 0.3f, 1f}, new Color[]{new Color(0.8f, 0.8f, 1f),
new Color(0.7f, 0.7f, 1f), new Color(0.6f, 0.6f, 1f)});
dialog.setContentPane(panel);
dialog.setVisible(true);
}
private class BackgroundPanel extends JPanel {
private static final long serialVersionUID = 1L;
BackgroundPanel() {
setOpaque(true);
}
@Override
protected void paintComponent(final Graphics g) {
final Graphics2D g2d = (Graphics2D) g;
g2d.setPaint(lpg);
g2d.fillRect(1, 1, getWidth() - 2, getHeight() - 2);
g2d.setColor(Color.BLACK);
g2d.drawRect(0, 0, getWidth() - 1, getHeight() - 1);
}
}
public static void main(final String[] args) {
try {
for (LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
System.out.println(info.getName());
if ("Nimbus".equals(info.getName())) {
UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (UnsupportedLookAndFeelException e) {
} catch (ClassNotFoundException e) {
} catch (InstantiationException e) {
} catch (IllegalAccessException e) {
}
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
NotificationPopup notificationPopup = new NotificationPopup();
}
});
}
}
这是我最终使用的代码:
GraphicsConfiguration gc = // ...
Rectangle bounds = gc.getBounds();
Insets screenInsets = Toolkit.getDefaultToolkit().getScreenInsets(gc);
Rectangle effectiveScreenArea = new Rectangle();
effectiveScreenArea.x = bounds.x + screenInsets.left;
effectiveScreenArea.y = bounds.y + screenInsets.top;
effectiveScreenArea.height = bounds.height - screenInsets.top - screenInsets.bottom;
effectiveScreenArea.width = bounds.width - screenInsets.left - screenInsets.right;
这是我编写的一种方法,它通过减去边距并将其在屏幕中居中来快速进行计算。
public void setToEffectiveScreenSize() {
double width, height, x, y;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
Insets bounds = Toolkit.getDefaultToolkit().getScreenInsets(frmMain.getGraphicsConfiguration());
// Calculate the height/length by subtracting the margins
// (x,y) = ( (screenHeight-windowHeight)/2, (screenWidth - windowWidth)/2 )
width = screenSize.getWidth() - bounds.left - bounds.right;
height = screenSize.getHeight() - bounds.top - bounds.bottom;
// Now center the new rectangle inside the screen
x = (screenSize.getHeight() - height) / 2.0;
y = (screenSize.getWidth() - width) / 2.0;
frmMain.setBounds((int)x,(int)y,(int)width,(int)height);
}