android - Bringing activity back from foreground

I stuck in a problem.
Suppose there is an activity A
now, user press Home key, and put A into background.
now, after remaining in background for a while, it will generate a notification.
On clicking on that notification, it will bring back the exact same activity which was in the background.
Like, after pressing home key, if user start the application again by clicking on the icon or from the recent launched history, then android re-opens exactly last activity in it's previous state.
Here, I dont want to detect which was the last activity. My activity is fixed, I just want to bring it back at its previous state on clicking on the notification ?
Is that possible ? how to do that ?
here is my code for notification,

    private void generateNotification(Context context, String message, String data) {   
    NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
    Notification notification = new Notification(R.drawable.notification, message,  System.currentTimeMillis());

    Intent notificationIntent = new Intent(context, MenuActivity.class);        
    //notificationIntent.setFlags(Notification.FLAG_ONGOING_EVENT | Notification.FLAG_NO_CLEAR);
    notificationIntent.setFlags(Intent.FLAG_ACTIVITY_LAUNCHED_FROM_HISTORY);

    Bundle bundle = new Bundle();
    bundle.putString("data",data);

    notificationIntent.putExtras(bundle);

    //Constants.NOTIFICATION_ID++;
    notification.setLatestEventInfo(context, context.getString(R.string.app_name), message, PendingIntent.getActivity(context, 0, notificationIntent, Notification.FLAG_ONGOING_EVENT | Notification.FLAG_NO_CLEAR));
    notification.flags |= Notification.FLAG_AUTO_CANCEL;
    notificationManager.notify(Constants.NOTIFICATION_ID, notification);            
}

Java: Print Array: IndexOutOfBoundsException: Index: 2, Size: 2

I am trying to print the contents of an array using System.out.print() but I encounter this error:

Exception in thread "AWT-EventQueue-0" java.lang.IndexOutOfBoundsException: Index: 2, Size: 2
at java.util.ArrayList.rangeCheck(ArrayList.java:604)
at java.util.ArrayList.get(ArrayList.java:382)
at Polymorphism.actionPerformed(Polymorphism.java:196)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)

at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6505)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6270)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4861)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)

at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2713)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:707)
at java.awt.EventQueue.access$000(EventQueue.java:101)
at java.awt.EventQueue$3.run(EventQueue.java:666)
at java.awt.EventQueue$3.run(EventQueue.java:664)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)

at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:680)
at java.awt.EventQueue$4.run(EventQueue.java:678)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:677)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)

at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

The line the error is referring to is line 3:

 else if (e.getSource() == printArray) {
        for (int q=0; q            System.out.print("Type: " + itemList.get(j).selectedType + "    ");
            System.out.print("Width: " + itemList.get(j).selectedWidth + "    ");

            System.out.print("Length: " + itemList.get(j).selectedLength + "    ");
    }
}

I don't have any debugger experience so I appreciate any help, thanks.

php - .htaccess issue with folder

I have an .htaccess file in my root directory with the following contents:

RewriteEngine On
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://website.com/$1 [R=301,L]
DirectoryIndex index.php
Options -Indexes

Works perfect in the root.

The problem is with subfolders. If I manually go to:
http://www.website.com/myfolder
it pushes me to:
https://website.com/myfolder/.php (404 error)

My goal is to always remove the "www" and redirect to SSL for the root and all subfolders. Obviously without the above error where it somehow leaves the ".php"

Please help!

Thanks!

How to save application state on Android

Possible Duplicate:
How do I save an Android application's state?

I have an Android app. The app crashes in one screen and the app exits. When I launch the app again, I need to launch another screen by checking some condition in the initial activity onCreate() method. Can we do this using preferences or SQLite?

Answer

You must override the onSaveInstanceState method. You can use preferences or SQLite, too.

Here's your exact duplicate question with code samples.

:: (double colon) operator in Java 8

I was exploring the Java 8 source and found this particular part of code very surprising:

//defined in IntPipeline.java
@Override
public final OptionalInt reduce(IntBinaryOperator op) {
    return evaluate(ReduceOps.makeInt(op));
}

@Override
public final OptionalInt max() {
    return reduce(Math::max); //this is the gotcha line
}


//defined in Math.java
public static int max(int a, int b) {
    return (a >= b) ? a : b;
}

Is Math::max something like a method pointer? How does a normal static method get converted to IntBinaryOperator?

Answer

Usually, one would call the reduce method using Math.max(int, int) as follows:

reduce(new IntBinaryOperator() {
    int applyAsInt(int left, int right) {
        return Math.max(left, right);
    }
});

That requires a lot of syntax for just calling Math.max. That's where lambda expressions come into play. Since Java 8 it is allowed to do the same thing in a much shorter way:

reduce((int left, int right) -> Math.max(left, right));

How does this work? The java compiler "detects", that you want to implement a method that accepts two ints and returns one int. This is equivalent to the formal parameters of the one and only method of interface IntBinaryOperator (the parameter of method reduce you want to call). So the compiler does the rest for you - it just assumes you want to implement IntBinaryOperator.

But as Math.max(int, int) itself fulfills the formal requirements of IntBinaryOperator, it can be used directly. Because Java 7 does not have any syntax that allows a method itself to be passed as an argument (you can only pass method results, but never method references), the :: syntax was introduced in Java 8 to reference methods:

reduce(Math::max);

Note that this will be interpreted by the compiler, not by the JVM at runtime! Although it produces different bytecodes for all three code snippets, they are semantically equal, so the last two can be considered to be short (and probably more efficient) versions of the IntBinaryOperator implementation above!

(See also Translation of Lambda Expressions)

character - Is Katherine Hepburn's shaking real or acted in On Golden Pond? - Movies & TV

Throughout the film, Hepburn's character, Ethel Thayer, is wobbling in a fashion that some older people do when they start to lose motor control (sometimes as a result of a degenerative disease).

Was she acting this, or was she actually affected by such a condition?

Answer

Katharine Hepburn's tremors in On Golden Pond were real. She developed essential tremors, a disease that can affect the extremities by causing them to involuntarily shake in varying degrees.

Per a website specializing in health-related information for older adults:

"...her tremulous voice and the persistent involuntary movement of her
head, particularly during her performance in "On Golden Pond." These are classic symptoms of essential tremor that has affected the head and voice. She never appeared to have any difficulty walking. Ms. Hepburn did not have Parkinson's Disease, and despite her "disability," she was able to perform for many, many years."

Here is an additional excerpt from a New York Times Q&A where someone asked "Why did Katharine Hepburn's head shake?":

Katharine Hepburn's ailment, recently discussed on television by her
niece Katharine Houghton, was not Parkinson's disease, but a
progressive yet treatable neurological disorder called essential
tremor. Ms. Hepburn's was referred to as familial tremor, the
inherited form. Each child of a parent with the disease has a 50
percent chance of inheriting a gene that causes it. In other cases,
there is no family history.

The disorder, which varies in location and severity, used to be called
palsy. The International Essential Tremor Foundation, which offers
information and helps search for a cure, says the disease stems from
abnormal communication among areas of the brain, including the
cerebellum, thalamus and brain stem. The group estimates that 10
million people in the United States and 200 million people worldwide
have some form of the problem, often undiagnosed.

Many do not seek treatment because they fear Parkinson's or think
tremors are part of aging. Shaking, usually starting with the hands,

can begin at any age but is more common in older people; tremors
starting with the head are more common in women.

c++ - Undefined symbol references in boost and CImg

I am new to using CImg and boost. I am getting undefined symbol references as mentioned below, in the code also shared below.

I am using this command line to build it: g++ -lboost_filesystem -lboost_system -L/usr/X11R6/lib -lm -lpthread -lX11 grayscaleConvertor.cpp &> errLog.txt

I am using the -l args in the compiler command. eg: -lboost_filesystem which I read on another post in stackoverflow, but that is not helping resolve the boost::filesystem:: symbols

locate CImg : /usr/include/CImg.h

locate boost: /usr/include/boost (plus more lines)

errLog.txt

/tmp/ccRIIPim.o: In function main':
grayscaleConvertor.cpp:(.text+0x179): undefined reference toboost::filesystem::path::extension() const'

grayscaleConvertor.cpp:(.text+0x213): undefined reference to boost::filesystem::path::filename() const'
/tmp/ccRIIPim.o: In function__static_initialization_and_destruction_0(int, int)':
grayscaleConvertor.cpp:(.text+0x68e): undefined reference to boost::system::generic_category()'
grayscaleConvertor.cpp:(.text+0x698): undefined reference toboost::system::generic_category()'
grayscaleConvertor.cpp:(.text+0x6a2): undefined reference to boost::system::system_category()'
/tmp/ccRIIPim.o: In functionboost::system::error_code::error_code()':
grayscaleConvertor.cpp:(.text._ZN5boost6system10error_codeC2Ev[_ZN5boost6system10error_codeC5Ev]+0x10): undefined reference to boost::system::system_category()'
/tmp/ccRIIPim.o: In functionboost::system::error_code::clear()':
grayscaleConvertor.cpp:(.text._ZN5boost6system10error_code5clearEv[_ZN5boost6system10error_code5clearEv]+0x10): undefined reference to boost::system::system_category()'
/tmp/ccRIIPim.o: In functionboost::filesystem::path::compare(std::__cxx11::basic_string, std::allocator > const&) const':

grayscaleConvertor.cpp:(.text._ZNK5boost10filesystem4path7compareERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE[_ZNK5boost10filesystem4path7compareERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE]+0x3b): undefined reference to boost::filesystem::path::compare(boost::filesystem::path const&) const'
/tmp/ccRIIPim.o: In functionboost::filesystem::exists(boost::filesystem::path const&)':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem6existsERKNS0_4pathE[_ZN5boost10filesystem6existsERKNS0_4pathE]+0x24): undefined reference to boost::filesystem::detail::status(boost::filesystem::path const&, boost::system::error_code*)'
/tmp/ccRIIPim.o: In functionboost::filesystem::is_directory(boost::filesystem::path const&)':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem12is_directoryERKNS0_4pathE[_ZN5boost10filesystem12is_directoryERKNS0_4pathE]+0x24): undefined reference to boost::filesystem::detail::status(boost::filesystem::path const&, boost::system::error_code*)'
/tmp/ccRIIPim.o: In functionboost::filesystem::is_regular_file(boost::filesystem::path const&)':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem15is_regular_fileERKNS0_4pathE[_ZN5boost10filesystem15is_regular_fileERKNS0_4pathE]+0x24): undefined reference to boost::filesystem::detail::status(boost::filesystem::path const&, boost::system::error_code*)'
/tmp/ccRIIPim.o: In functionboost::filesystem::directory_entry::status(boost::system::error_code&) const':
grayscaleConvertor.cpp:(.text._ZNK5boost10filesystem15directory_entry6statusERNS_6system10error_codeE[_ZNK5boost10filesystem15directory_entry6statusERNS_6system10error_codeE]+0x31): undefined reference to boost::filesystem::directory_entry::m_get_status(boost::system::error_code*) const'
/tmp/ccRIIPim.o: In functionboost::filesystem::directory_entry::symlink_status(boost::system::error_code&) const':

grayscaleConvertor.cpp:(.text._ZNK5boost10filesystem15directory_entry14symlink_statusERNS_6system10error_codeE[_ZNK5boost10filesystem15directory_entry14symlink_statusERNS_6system10error_codeE]+0x31): undefined reference to boost::filesystem::directory_entry::m_get_symlink_status(boost::system::error_code*) const'
/tmp/ccRIIPim.o: In functionboost::filesystem::detail::dir_itr_imp::~dir_itr_imp()':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem6detail11dir_itr_impD2Ev[_ZN5boost10filesystem6detail11dir_itr_impD5Ev]+0x2e): undefined reference to boost::filesystem::detail::dir_itr_close(void*&, void*&)'
/tmp/ccRIIPim.o: In functionboost::filesystem::directory_iterator::directory_iterator(boost::filesystem::path const&)':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem18directory_iteratorC2ERKNS0_4pathE[_ZN5boost10filesystem18directory_iteratorC5ERKNS0_4pathE]+0x4a): undefined reference to boost::filesystem::detail::directory_iterator_construct(boost::filesystem::directory_iterator&, boost::filesystem::path const&, boost::system::error_code*)'
/tmp/ccRIIPim.o: In functionboost::filesystem::directory_iterator::directory_iterator(boost::filesystem::path const&, boost::system::error_code&)':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem18directory_iteratorC2ERKNS0_4pathERNS_6system10error_codeE[_ZN5boost10filesystem18directory_iteratorC5ERKNS0_4pathERNS_6system10error_codeE]+0x4b): undefined reference to boost::filesystem::detail::directory_iterator_construct(boost::filesystem::directory_iterator&, boost::filesystem::path const&, boost::system::error_code*)'
/tmp/ccRIIPim.o: In functionboost::filesystem::directory_iterator::increment()':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem18directory_iterator9incrementEv[_ZN5boost10filesystem18directory_iterator9incrementEv]+0xf): undefined reference to boost::filesystem::detail::directory_iterator_increment(boost::filesystem::directory_iterator&, boost::system::error_code*)'
/tmp/ccRIIPim.o: In functioncimg_library::cimg::Mutex_info::trylock(unsigned int)':

grayscaleConvertor.cpp:(.text._ZN12cimg_library4cimg10Mutex_info7trylockEj[_ZN12cimg_library4cimg10Mutex_info7trylockEj]+0x1c): undefined reference to pthread_mutex_trylock'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::screen_width()':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay12screen_widthEv[_ZN12cimg_library11CImgDisplay12screen_widthEv]+0x26): undefined reference to XOpenDisplay'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay12screen_widthEv[_ZN12cimg_library11CImgDisplay12screen_widthEv]+0x96): undefined reference toXCloseDisplay'
/tmp/ccRIIPim.o: In function cimg_library::CImgDisplay::screen_height()':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay13screen_heightEv[_ZN12cimg_library11CImgDisplay13screen_heightEv]+0x26): undefined reference toXOpenDisplay'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay13screen_heightEv[_ZN12cimg_library11CImgDisplay13screen_heightEv]+0x96): undefined reference to XCloseDisplay'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::_handle_events(_XEvent const*)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0xb5): undefined reference to XUnmapWindow'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x112): undefined reference toXCheckWindowEvent'

grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x1f0): undefined reference to XResizeWindow'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x2c2): undefined reference toXCheckWindowEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x317): undefined reference to XGetWindowAttributes'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x335): undefined reference toXSync'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x356): undefined reference to XSetInputFocus'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x472): undefined reference toXCheckWindowEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x5c4): undefined reference to XCheckWindowEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x601): undefined reference toXLookupString'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x635): undefined reference to XQueryKeymap'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x6d8): undefined reference toXLookupString'

grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x71b): undefined reference to XCheckWindowEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x7f0): undefined reference toXCheckWindowEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent[_ZN12cimg_library11CImgDisplay14_handle_eventsEPK7_XEvent]+0x861): undefined reference to XCheckWindowEvent'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::_events_thread(void*)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_events_threadEPv[_ZN12cimg_library11CImgDisplay14_events_threadEPv]+0x6a): undefined reference to XCheckTypedEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_events_threadEPv[_ZN12cimg_library11CImgDisplay14_events_threadEPv]+0x94): undefined reference toXCheckMaskEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay14_events_threadEPv[_ZN12cimg_library11CImgDisplay14_events_threadEPv]+0x14c): undefined reference to pthread_testcancel'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::_set_colormap(unsigned long&, unsigned int)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay13_set_colormapERmj[_ZN12cimg_library11CImgDisplay13_set_colormapERmj]+0x2a2): undefined reference to XStoreColors'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::_map_window()':

grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay11_map_windowEv[_ZN12cimg_library11CImgDisplay11_map_windowEv]+0x50): undefined reference to XMapRaised'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay11_map_windowEv[_ZN12cimg_library11CImgDisplay11_map_windowEv]+0x74): undefined reference toXWindowEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay11_map_windowEv[_ZN12cimg_library11CImgDisplay11_map_windowEv]+0xcb): undefined reference to XGetWindowAttributes'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay11_map_windowEv[_ZN12cimg_library11CImgDisplay11_map_windowEv]+0xe9): undefined reference toXSync'
/tmp/ccRIIPim.o: In function cimg_library::CImgDisplay::_paint(bool)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay6_paintEb[_ZN12cimg_library11CImgDisplay6_paintEb]+0xcd): undefined reference toXSendEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay6_paintEb[_ZN12cimg_library11CImgDisplay6_paintEb]+0x130): undefined reference to XPutImage'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::_init_fullscreen()':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0xfe): undefined reference to XCreateWindow'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0x1df): undefined reference toXCreateImage'

grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0x208): undefined reference to XSelectInput'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0x226): undefined reference toXMapRaised'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0x24a): undefined reference to XWindowEvent'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0x2c1): undefined reference toXPutImage'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0x2e6): undefined reference to XGetWindowAttributes'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay16_init_fullscreenEv[_ZN12cimg_library11CImgDisplay16_init_fullscreenEv]+0x304): undefined reference toXSync'
/tmp/ccRIIPim.o: In function cimg_library::CImgDisplay::_desinit_fullscreen()':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay19_desinit_fullscreenEv[_ZN12cimg_library11CImgDisplay19_desinit_fullscreenEv]+0x28): undefined reference toXUngrabKeyboard'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay19_desinit_fullscreenEv[_ZN12cimg_library11CImgDisplay19_desinit_fullscreenEv]+0x4d): undefined reference to XDestroyWindow'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::_assign(unsigned int, unsigned int, char const*, unsigned int, bool, bool)':

grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0xf7): undefined reference to XOpenDisplay'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x330): undefined reference toXVisualIDFromVisual'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x34b): undefined reference to XGetVisualInfo'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x392): undefined reference toXFree'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x3d2): undefined reference to pthread_create'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x57c): undefined reference toXCreateWindow'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x5e3): undefined reference to XCreateSimpleWindow'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x614): undefined reference toXSelectInput'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x650): undefined reference to XStoreName'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x6ab): undefined reference toXCreateColormap'

grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x703): undefined reference to XSetWindowColormap'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x70b): undefined reference toXAllocClassHint'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x741): undefined reference to XSetClassHint'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x74f): undefined reference toXFree'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x84a): undefined reference to XCreateImage'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x870): undefined reference toXInternAtom'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x896): undefined reference to XInternAtom'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x8ce): undefined reference toXSetWMProtocols'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb[_ZN12cimg_library11CImgDisplay7_assignEjjPKcjbb]+0x902): undefined reference to XGrabKeyboard'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::assign()':

grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay6assignEv[_ZN12cimg_library11CImgDisplay6assignEv]+0x10c): undefined reference to XDestroyWindow'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay6assignEv[_ZN12cimg_library11CImgDisplay6assignEv]+0x17b): undefined reference toXFreeColormap'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay6assignEv[_ZN12cimg_library11CImgDisplay6assignEv]+0x198): undefined reference to XSync'
/tmp/ccRIIPim.o: In functioncimg_library::CImgDisplay::resize(int, int, bool)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay6resizeEiib[_ZN12cimg_library11CImgDisplay6resizeEiib]+0x208): undefined reference to XResizeWindow'
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay6resizeEiib[_ZN12cimg_library11CImgDisplay6resizeEiib]+0x227): undefined reference toXGetWindowAttributes'
/tmp/ccRIIPim.o: In function cimg_library::CImgDisplay::move(int, int)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay4moveEii[_ZN12cimg_library11CImgDisplay4moveEii]+0x72): undefined reference toXMoveWindow'
/tmp/ccRIIPim.o: In function void cimg_library::CImgDisplay::_resize(unsigned char, unsigned int, unsigned int, bool)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_resizeIhEEvT_jjb[_ZN12cimg_library11CImgDisplay7_resizeIhEEvT_jjb]+0x106): undefined reference toXCreateImage'

/tmp/ccRIIPim.o: In function void cimg_library::CImgDisplay::_resize(unsigned short, unsigned int, unsigned int, bool)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_resizeItEEvT_jjb[_ZN12cimg_library11CImgDisplay7_resizeItEEvT_jjb]+0x10b): undefined reference toXCreateImage'
/tmp/ccRIIPim.o: In function void cimg_library::CImgDisplay::_resize(unsigned int, unsigned int, unsigned int, bool)':
grayscaleConvertor.cpp:(.text._ZN12cimg_library11CImgDisplay7_resizeIjEEvT_jjb[_ZN12cimg_library11CImgDisplay7_resizeIjEEvT_jjb]+0x106): undefined reference toXCreateImage'
/tmp/ccRIIPim.o: In function boost::filesystem::path::path(boost::filesystem::directory_entry const&, boost::enable_if::type>, void>::type*)':
grayscaleConvertor.cpp:(.text._ZN5boost10filesystem4pathC2INS0_15directory_entryEEERKT_PNS_9enable_ifINS0_11path_traits11is_pathableINS_5decayIS4_E4typeEEEvE4typeE[_ZN5boost10filesystem4pathC5INS0_15directory_entryEEERKT_PNS_9enable_ifINS0_11path_traits11is_pathableINS_5decayIS4_E4typeEEEvE4typeE]+0x21): undefined reference toboost::filesystem::path_traits::dispatch(boost::filesystem::directory_entry const&, std::__cxx11::basic_string, std::allocator >&)'
collect2: error: ld returned 1 exit status

grayscaleConvertor.cpp

#define BOOST_FILESYSTEM_VERSION 3
#define BOOST_FILESYSTEM_NO_DEPRECATED 
#include 

#include "CImg.h"
#include  
#include 

using namespace cimg_library;

using namespace std;

namespace fs = ::boost::filesystem;

int main()
{
    const string ext = ".png";
    fs::path root("/Downloads/testdata1/");

    if(!fs::exists(root) || !fs::is_directory(root)) return -1;


    fs::recursive_directory_iterator it(root);
    fs::recursive_directory_iterator endit;

    while(it != endit)
    {
        if(fs::is_regular_file(*it) && it->path().extension()==ext)
        {
            CImg image(it->path().filename().string().c_str()),
                gray(image.width(), image.height(), 1, 1, 0),

                grayWeight(image.width(), image.height(), 1, 1, 0),
                imgR(image.width(), image.height(), 1, 3, 0),
                imgG(image.width(), image.height(), 1, 3, 0),
                imgB(image.width(), image.height(), 1, 3, 0);
        }
        ++it;
    }
    return 0;
}