我是Java SE开发人员，我们的程序仅在Windows OS上运行，该程序需要打开文件并在UI中显示，我们在JInternalFrame中显示文件内容，并且在打开文件时始终显示setselected(true)。< / p>
最近，我们将程序从JRE1.6.0_41更新到了JRE1.8.0_144，解决了一个重大错误，并注意到在JRE1.8.0_144中，当程序（JFrame）不在焦点时，调用setselected(true)如果是JFrame中的JInternalFrame，则JFrame将在任务栏中闪烁，而JRE1.6.0_41不会。一些客户认为这很烦人，因为他们不得不经常打开文件。
所以问题是：
（1）我可以关闭该功能吗？
（2）如果不能，是否还有另一种方法可以避免闪烁效果，而我仍然可以在JInternalFrame上setSelected()？
如果我没有很好地解释它，这是演示警报效果的示例代码，请运行该程序并将其最小化到任务栏中切换到另一个窗口，然后它应该会闪烁。我已经在Windows 7，Windows 8.1和Windows 10上进行了测试，它们都具有相同的警报效果。
import javax.swing.JInternalFrame;
import javax.swing.SwingUtilities;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import java.awt.*;
/*
* Copy and modified by Oracle sample code "InternalFrameDemo.java"
*/
public class Login extends JFrame {
JDesktopPane desktop;
private int m_iFrameCounter = 0;
public Login() {
super("InternalFrameDemo");
//Make the big window be indented 50 pixels from each edge
//of the screen.
int inset = 50;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(inset, inset,
screenSize.width - inset*2,
screenSize.height - inset*2);
//Set up the GUI.
desktop = new JDesktopPane(); //a specialized layered pane
createFrame(); //create first "window"
setContentPane(desktop);
//Make dragging a little faster but perhaps uglier.
desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);
// Add new frame every second
Thread addFrameThread = new Thread() {
@Override
public void run() {
while(true) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
createFrame();
}
});
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
addFrameThread.start();
}
//Create a new internal frame.
protected void createFrame() {
JInternalFrame frame = new JInternalFrame();
frame.setTitle("" + m_iFrameCounter);
frame.setSize(100, 100);
frame.setLocation(0, 0);
frame.setVisible(true); //necessary as of 1.3
desktop.add(frame);
frame.moveToFront();
try {
frame.setSelected(true);
} catch (java.beans.PropertyVetoException e) {}
m_iFrameCounter++;
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
Login frame = new Login();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Display the window.
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
更新01
这是更新代码，当JFrame具有焦点或JFrame获得焦点时，此更新代码采用@camickr建议在JInternalFrame上添加KeyboardFocusManager和WindowListener，仅在setselected(true)上添加JInternalFrame，但是如果您经常切换窗口，我认为这是因为JFrame在JInternalFrame的setselected(true)之前失去了焦点。也许有一种方法可以改善代码？
import javax.swing.JInternalFrame;
import javax.swing.SwingUtilities;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import java.awt.*;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.beans.PropertyVetoException;
/*
* Copy and modified by Oracle sample code "InternalFrameDemo.java"
*/
public class Login extends JFrame {
JDesktopPane desktop;
private int m_iFrameCounter = 0;
private JInternalFrame m_InternalFrameWaitSelected = null;
public Login() {
super("InternalFrameDemo");
//Make the big window be indented 50 pixels from each edge
//of the screen.
int inset = 50;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(inset, inset,
screenSize.width - inset*2,
screenSize.height - inset*2);
//Set up the GUI.
desktop = new JDesktopPane(); //a specialized layered pane
createFrame(); //create first "window"
setContentPane(desktop);
//Make dragging a little faster but perhaps uglier.
desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);
/********************************************* update codes *********************************************/
//Add window listener to set last JInternalframe selected when JFrame activated
this.addWindowListener(new WindowListener() {
@Override
public void windowOpened(WindowEvent e) {
}
@Override
public void windowClosing(WindowEvent e) {
}
@Override
public void windowClosed(WindowEvent e) {
}
@Override
public void windowIconified(WindowEvent e) {
}
@Override
public void windowDeiconified(WindowEvent e) {
}
@Override
public void windowActivated(WindowEvent e) {
if (m_InternalFrameWaitSelected != null) {
try {
m_InternalFrameWaitSelected.setSelected(true);
} catch (PropertyVetoException e1) {
e1.printStackTrace();
}
m_InternalFrameWaitSelected = null;
}
}
@Override
public void windowDeactivated(WindowEvent e) {
}
});
/********************************************* update codes *********************************************/
// Add new frame every 50 millisecond
Thread addFrameThread = new Thread() {
@Override
public void run() {
while(true) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
createFrame();
}
});
try {
Thread.sleep(50);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
addFrameThread.start();
}
//Create a new internal frame.
protected void createFrame() {
JInternalFrame frame = new JInternalFrame();
frame.setTitle("" + m_iFrameCounter);
frame.setSize(100, 100);
frame.setLocation(0, 0);
frame.setVisible(true); //necessary as of 1.3
desktop.add(frame);
frame.moveToFront();
/********************************************* update codes *********************************************/
// Only setselect(true) when JFrame is focus owner
if (KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner() != null &&
SwingUtilities.isDescendingFrom(KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner(), this)) {
try {
frame.setSelected(true);
} catch (java.beans.PropertyVetoException e) {}
} else {
m_InternalFrameWaitSelected = frame;
}
/********************************************* update codes *********************************************/
m_iFrameCounter++;
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
Login frame = new Login();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Display the window.
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
更新02
尝试getGlobalActiveWindow()和windowActivated/windowDeactivated时，如果频繁切换窗口，警报仍然会发生。下面是测试代码：
getGlobalActiveWindow（）
import javax.swing.JInternalFrame;
import javax.swing.SwingUtilities;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import java.awt.*;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.beans.PropertyVetoException;
/*
* Copy and modified by Oracle sample code "InternalFrameDemo.java"
*/
public class Login extends JFrame {
JDesktopPane desktop;
private int m_iFrameCounter = 0;
private JInternalFrame m_InternalFrameWaitSelected = null;
/********************************************* update codes *********************************************/
private MyDefaultKeyboardFocusManager m_MyKeyboardFocusManager = new MyDefaultKeyboardFocusManager();
public class MyDefaultKeyboardFocusManager extends DefaultKeyboardFocusManager {
//The method is protected, need to add public method to call it
public Window myGetGlobalActiveWindow() {
return this.getGlobalActiveWindow();
}
}
/********************************************* update codes *********************************************/
public Login() {
super("InternalFrameDemo");
//Make the big window be indented 50 pixels from each edge
//of the screen.
int inset = 50;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(inset, inset,
screenSize.width - inset*2,
screenSize.height - inset*2);
//Set up the GUI.
desktop = new JDesktopPane(); //a specialized layered pane
setContentPane(desktop);
//Make dragging a little faster but perhaps uglier.
desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);
/********************************************* update codes *********************************************/
KeyboardFocusManager.setCurrentKeyboardFocusManager(m_MyKeyboardFocusManager);
/********************************************* update codes *********************************************/
//Add window listener to set last JInternalframe selected when JFrame activated
this.addWindowListener(new WindowListener() {
@Override
public void windowOpened(WindowEvent e) {
}
@Override
public void windowClosing(WindowEvent e) {
}
@Override
public void windowClosed(WindowEvent e) {
}
@Override
public void windowIconified(WindowEvent e) {
}
@Override
public void windowDeiconified(WindowEvent e) {
}
@Override
public void windowActivated(WindowEvent e) {
if (m_InternalFrameWaitSelected != null) {
try {
m_InternalFrameWaitSelected.setSelected(true);
} catch (PropertyVetoException e1) {
e1.printStackTrace();
}
m_InternalFrameWaitSelected = null;
}
}
@Override
public void windowDeactivated(WindowEvent e) {
}
});
// Add new frame every 50 millisecond
Thread addFrameThread = new Thread() {
@Override
public void run() {
while(true) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
createFrame();
}
});
try {
Thread.sleep(50);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
addFrameThread.start();
}
//Create a new internal frame.
protected void createFrame() {
JInternalFrame frame = new JInternalFrame();
frame.setTitle("" + m_iFrameCounter);
frame.setSize(100, 100);
frame.setLocation(0, 0);
frame.setVisible(true); //necessary as of 1.3
desktop.add(frame);
frame.moveToFront();
/********************************************* update codes *********************************************/
// Only setselect(true) when JFrame is active
if (m_MyKeyboardFocusManager.myGetGlobalActiveWindow() == this) {
try {
frame.setSelected(true);
} catch (java.beans.PropertyVetoException e) {}
} else {
m_InternalFrameWaitSelected = frame;
}
/********************************************* update codes *********************************************/
m_iFrameCounter++;
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
Login frame = new Login();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Display the window.
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
windowActivated / windowDeactivated
import javax.swing.JInternalFrame;
import javax.swing.SwingUtilities;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import java.awt.*;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.beans.PropertyVetoException;
/*
* Copy and modified by Oracle sample code "InternalFrameDemo.java"
*/
public class Login extends JFrame {
JDesktopPane desktop;
private int m_iFrameCounter = 0;
private JInternalFrame m_InternalFrameWaitSelected = null;
/********************************************* update codes *********************************************/
private boolean m_bIsFrameActive = false;
/********************************************* update codes *********************************************/
public Login() {
super("InternalFrameDemo");
//Make the big window be indented 50 pixels from each edge
//of the screen.
int inset = 50;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(inset, inset,
screenSize.width - inset*2,
screenSize.height - inset*2);
//Set up the GUI.
desktop = new JDesktopPane(); //a specialized layered pane
setContentPane(desktop);
//Make dragging a little faster but perhaps uglier.
desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);
/********************************************* update codes *********************************************/
//Add window listener to set last JInternalframe selected when JFrame activated
this.addWindowListener(new WindowListener() {
@Override
public void windowOpened(WindowEvent e) {
}
@Override
public void windowClosing(WindowEvent e) {
}
@Override
public void windowClosed(WindowEvent e) {
}
@Override
public void windowIconified(WindowEvent e) {
}
@Override
public void windowDeiconified(WindowEvent e) {
}
@Override
public void windowActivated(WindowEvent e) {
m_bIsFrameActive = true;
if (m_InternalFrameWaitSelected != null) {
try {
m_InternalFrameWaitSelected.setSelected(true);
} catch (PropertyVetoException e1) {
e1.printStackTrace();
}
m_InternalFrameWaitSelected = null;
}
}
@Override
public void windowDeactivated(WindowEvent e) {
m_bIsFrameActive = false;
}
});
/********************************************* update codes *********************************************/
// Add new frame every 50 millisecond
Thread addFrameThread = new Thread() {
@Override
public void run() {
while(true) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
createFrame();
}
});
try {
Thread.sleep(50);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
addFrameThread.start();
}
//Create a new internal frame.
protected void createFrame() {
JInternalFrame frame = new JInternalFrame();
frame.setTitle("" + m_iFrameCounter);
frame.setSize(100, 100);
frame.setLocation(0, 0);
frame.setVisible(true); //necessary as of 1.3
desktop.add(frame);
frame.moveToFront();
/********************************************* update codes *********************************************/
// Only setselect(true) when JFrame is active
if (m_bIsFrameActive) {
try {
frame.setSelected(true);
} catch (java.beans.PropertyVetoException e) {}
} else {
m_InternalFrameWaitSelected = frame;
}
/********************************************* update codes *********************************************/
m_iFrameCounter++;
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
Login frame = new Login();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Display the window.
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
答案 0 :(得分：0)
我们在JInternalFrame中显示文件内容，并在打开文件时始终将其设置为setselected（true）。
不知道如何停止任务栏上的闪烁，但是您可以通过不自动调用setSelected（）来更改行为。
您可以例如：
仅在框架为活动窗口时调用setSelected()。您可以使用KeyboardFocusManager检查窗口是否聚焦。
向框架中添加WindowListener并处理windowActivated事件，以在最近打开的内部框架上调用setSelected（）方法。
编辑：
运行程序并将其最小化到任务栏中，
首先，我想澄清一下，如果将框架最小化到任务栏，则图标闪烁没有问题。
仅当我单击另一个应用程序时，该图标才会闪烁，并且登录框仍处于打开状态时会失去焦点。
如果您经常切换窗口，警报仍然会发生
我将您的代码更改为：
//if (KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner() != null &&
// SwingUtilities.isDescendingFrom(KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner(), this)) {
if (KeyboardFocusManager.getCurrentKeyboardFocusManager().getActiveWindow() == this)
{
try
{
System.out.println("active");
frame.setSelected(true);
}
catch (java.beans.PropertyVetoException e) {}
}
else
{
System.out.println("not");
// frame = m_InternalFrameWaitSelected;
m_InternalFrameWaitSelected = frame;
}
，我注意到有时即使在另一个窗口中玩游戏，也会显示“ active”。所以由于某种原因，KeyboardFocusManager返回的值不正确（或者我不知道该方法应如何工作？）
因此，也许您可以尝试使用getGlobalActiveWindow()方法来查看它是否有所不同。
如果没有，那么我的下一个建议是忘记KeyboardFocusManager并管理一个布尔变量，该变量指示框架是否处于活动状态。因此，您将在windowActivated中将变量设置为true，在windowDeactivated中将变量设置为false。然后在创建框架时测试此变量。
还要注意我如何更改以下代码：
// frame = m_InternalFrameWaitSelected;
m_InternalFrameWaitSelected = frame;
答案 1 :(得分：0)
如果有人对答案感兴趣，在我跟踪到JInternalFrame中的源代码后，我发现眨眼效应是由调用requestFocus()时setSelected(true)引起的，所以我决定继承JInternalFrame并将requestFocus()替换为requestFocusInWindow()，现在闪烁效果消失了。
这是我针对该问题的最终解决方案：
import javax.swing.JInternalFrame;
import javax.swing.SwingUtilities;
import sun.swing.SwingUtilities2;
import javax.swing.InternalFrameFocusTraversalPolicy;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import java.awt.*;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.beans.PropertyVetoException;
/*
* Copy and modified by Oracle sample code "InternalFrameDemo.java"
*/
public class Login extends JFrame {
JDesktopPane desktop;
private int m_iFrameCounter = 0;
/**
* This class is created to handle problem that program would blink in taskbar
* when call setSelected(true) on JInternalFrame base on JRE1.8.0_144, the only different content is
* use lastFocusOwner.requestFocusInWindow(); instead of lastFocusOwner.requestFocus();
* in method restoreSubcomponentFocus()
*
*/
public class MyInternalFrame extends JInternalFrame {
private Component lastFocusOwner;
private final String BASE_JRE_VERSION = "1.8.0_144";
public MyInternalFrame() {
_checkJavaVersion();
}
public MyInternalFrame(String title) {
super(title);
_checkJavaVersion();
}
public MyInternalFrame(String title, boolean resizable) {
super(title, resizable);
_checkJavaVersion();
}
public MyInternalFrame(String title, boolean resizable, boolean closable) {
super(title, resizable, closable);
_checkJavaVersion();
}
public MyInternalFrame(String title, boolean resizable, boolean closable, boolean maximizable) {
super(title, resizable, closable, maximizable);
_checkJavaVersion();
}
public MyInternalFrame(String title, boolean resizable, boolean closable, boolean maximizable, boolean iconifiable) {
super(title, resizable, closable, maximizable, iconifiable);
_checkJavaVersion();
}
private void _checkJavaVersion() {
if (!BASE_JRE_VERSION.equals(System.getProperty("java.version")))
System.err.println(String.format("%s is not compatible with current Java runtime version : %s ", this.getClass().toString(), System.getProperty("java.version")));
}
@Override
public void restoreSubcomponentFocus() {
if (isIcon()) {
SwingUtilities2.compositeRequestFocus(getDesktopIcon());
}
else {
Component component = KeyboardFocusManager.getCurrentKeyboardFocusManager().getPermanentFocusOwner();
if ((component == null) || !SwingUtilities.isDescendingFrom(component, this)) {
// FocusPropertyChangeListener will eventually update
// lastFocusOwner. As focus requests are asynchronous
// lastFocusOwner may be accessed before it has been correctly
// updated. To avoid any problems, lastFocusOwner is immediately
// set, assuming the request will succeed.
setLastFocusOwner(getMostRecentFocusOwner());
if (lastFocusOwner == null) {
// Make sure focus is restored somewhere, so that
// we don't leave a focused component in another frame while
// this frame is selected.
setLastFocusOwner(getContentPane());
}
lastFocusOwner.requestFocusInWindow();
}
}
}
private void setLastFocusOwner(Component component) {
lastFocusOwner = component;
}
@Override
public Component getMostRecentFocusOwner() {
if (isSelected()) {
return getFocusOwner();
}
if (lastFocusOwner != null) {
return lastFocusOwner;
}
FocusTraversalPolicy policy = getFocusTraversalPolicy();
if (policy instanceof InternalFrameFocusTraversalPolicy) {
return ((InternalFrameFocusTraversalPolicy)policy).
getInitialComponent(this);
}
Component toFocus = policy.getDefaultComponent(this);
if (toFocus != null) {
return toFocus;
}
return getContentPane();
}
@Override
public Component getFocusOwner() {
if (isSelected()) {
return lastFocusOwner;
}
return null;
}
}
public Login() {
super("InternalFrameDemo");
//Make the big window be indented 50 pixels from each edge
//of the screen.
int inset = 50;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(inset, inset,
screenSize.width - inset*2,
screenSize.height - inset*2);
//Set up the GUI.
desktop = new JDesktopPane(); //a specialized layered pane
setContentPane(desktop);
//Make dragging a little faster but perhaps uglier.
desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);
// Add new frame every 50 millisecond
Thread addFrameThread = new Thread() {
@Override
public void run() {
while(true) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
createFrame();
}
});
try {
Thread.sleep(50);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
addFrameThread.start();
}
//Create a new internal frame.
protected void createFrame() {
JInternalFrame frame = new MyInternalFrame();
frame.setTitle("" + m_iFrameCounter);
frame.setSize(100, 100);
frame.setLocation(0, 0);
frame.setVisible(true); //necessary as of 1.3
desktop.add(frame);
frame.moveToFront();
try {
frame.setSelected(true);
} catch (java.beans.PropertyVetoException e) {}
m_iFrameCounter++;
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
Login frame = new Login();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Display the window.
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}