Java基础 awt Frame 窗体在屏幕的中间显示

•     JDK ：OpenJDK-11
•      OS ：CentOS 7.6.1810
•      IDE ：Eclipse 2019‑03
• typesetting ：Markdown

 

code

package per.jizuiku.gui;

import java.awt.Component;
import java.awt.Frame;
import java.awt.Toolkit;

/**
 * @author 给最苦
 * @date 2019/06/30
 * @blog www.cnblogs.com/jizuiku
 */
public class Demo {

    /**
     * @param args
     */
    public static void main(String[] args) {
        Frame f = new Frame();

        // 设置大小
        int width = 400;
        int height = 500;
        f.setSize(width, height);

        // 屏幕中间显示窗体
        center(f);

        // 可见
        f.setVisible(true);

    }

    /**
     *
     * @param c
     */
    public static void center(Component c) {
        Toolkit kit = Toolkit.getDefaultToolkit();
        int x = (kit.getScreenSize().width - c.getWidth()) / 2;
        int y = (kit.getScreenSize().height - c.getHeight()) / 2;
        c.setLocation(x, y);
    }

}

 

sourceCode

/**
    * Gets the size of the screen.  On systems with multiple displays, the
    * primary display is used.  Multi-screen aware display dimensions are
    * available from {@code GraphicsConfiguration} and
    * {@code GraphicsDevice}.
    * @return    the size of this toolkit's screen, in pixels.
    * @exception HeadlessException if GraphicsEnvironment.isHeadless()
    * returns true
    * @see       java.awt.GraphicsConfiguration#getBounds
    * @see       java.awt.GraphicsDevice#getDisplayMode
    * @see       java.awt.GraphicsEnvironment#isHeadless
    */
public abstract Dimension getScreenSize()
    throws HeadlessException;

/**
    * Returns the current width of this component.
    * This method is preferable to writing
    * {@code component.getBounds().width},
    * or {@code component.getSize().width} because it
    * doesn't cause any heap allocations.
    *
    * @return the current width of this component
    * @since 1.2
    */
public int getWidth() {
    return width;
}

 

resource

• [ JDK ] openjdk.java.net
• [ doc - 参考 ] docs.oracle.com/en/java/javase/11
• [ 规范 - 推荐 ] yq.aliyun.com/articles/69327
• [ 规范 - 推荐 ] google.github.io/styleguide
• [ 源码 ] hg.openjdk.java.net
• [ OS ] www.centos.org
• [ IDE ] www.eclipse.org/downloads/packages
• [ 平台 ] www.cnblogs.com

 

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感谢帮助过 给最苦 的人们。

Java、Groovy和Scala等基于JVM的语言，优秀，值得学习。

规范的命名和代码格式等，有助于沟通和理解。

JVM的配置、监控与优化，比较实用，值得学习。