Ok, after some more digging into the docs, I found it really is a new class, it has improvements, but it is only available in Qt5, so you can&#39;t use it if you want to compile on both Qt4 and Qt5:

&gt; Notes for QRegExp Users
&gt;
&gt; The QRegularExpression class introduced in Qt 5 is a big improvement upon QRegExp, in terms of APIs offered, supported pattern syntax and speed of execution. The biggest difference is that QRegularExpression simply holds a regular expression, **and it&#39;s not modified** when a match is requested. Instead, a QRegularExpressionMatch object is returned, in order to check the result of a match and extract the captured substring. The same applies with global matching and QRegularExpressionMatchIterator.



At least for Qt 4.8. I can give a very practical reason to use ``QRegularExpressions`` instead of ``QRegExp``:

Do these look dangerous to you?

    int index = myQString.indexOf(myQRegExp);
    bool okay = myQString.contains(myQRegExp);

Both lines can corrupt your heap, crash or hang your application. I experienced heap corruption and hang with Qt 4.8. The blog post [QString::indexOf() versus Qt 4.5][1] explains that ``QString::indexOf()`` modifies a ``const QRegExp`` object. ``QString::contains()`` inlines ``QString::indexOf()`` so it&#39;s the same problem.

If you&#39;re stuck with Qt4 and thus QRegExp, you could use

    int index = myQRegExp.indexIn(myQString);
    bool okay = (myQRegExp.indexIn(myQString) != -1); 

in your sources instead. Or patch the Qt Sources.


  [1]: http://blog.qt.io/blog/2008/11/04/910/

In using webpack to build my project, I typically require modules in CommonJS from npm modules. I need moment-timezone in my project, however in building the package you must also build all the data from moment-timezone, which can be quite a lot. 

Additionally the build is failing with the following error:

    ERROR in ./~/moment-timezone/data/packed/latest.json
    Module parse failed: /site/node_modules/moment-timezone/data/packed/latest.json Line 2: Unexpected token :
    You may need an appropriate loader to handle this file type.
    | {
    | 	&quot;version&quot;: &quot;2015a&quot;,
    | 	&quot;zones&quot;: [
    | 		&quot;Africa/Abidjan|LMT GMT|g.8 0|01|-2ldXH.Q&quot;,
    @ ./~/moment-timezone/index.js 4:15-51

At this point I am not as concerned with the build failing, as I am about the size of the build if it actually succeeds. Though, obviously the failing build will need to be addressed too at some point.

I would appreciate any pointers on how to handle this, especially if any of you have encountered this same issue using webpack (or browserify too, probably).

How should I use moment-timezone with webpack?

Is it possible and what would be the most efficient neat method to add a column to Data Frame? 

More specifically, column may serve as Row IDs for the existing Data Frame.

In a simplified case, reading from file and not tokenizing it, I can think of something as below (in Scala), but it completes with errors (at line 3), and anyways doesn&#39;t look like the best route possible: 

    var dataDF = sc.textFile(&quot;path/file&quot;).toDF() 
    val rowDF = sc.parallelize(1 to DataDF.count().toInt).toDF(&quot;ID&quot;) 
    dataDF = dataDF.withColumn(&quot;ID&quot;, rowDF(&quot;ID&quot;)) 

Append a column to Data Frame in Apache Spark 1.3

I see there is a new class for regular expressions - `QRegularExpression`. Is it just a typedef for QRegExp, or a new class, or what? And why do we need it, we already have QRegExp?

Is there any difference between QRegularExpression and QRegExp?

<p>I see there is a new class for regular expressions - <code>QRegularExpression</code>. Is it just a typedef for QRegExp, or a new class, or what? And why do we need it, we already have QRegExp?</p>


I&#39;ve worked with linked lists before extensively in Java, but I&#39;m very new to C++. I was using this node class that was given to me in a project just fine

    class Node
    {
      public:
       Node(int data);
    
       int m_data;
       Node *m_next;
    };

but I had one question that wasn&#39;t answered very well. Why is it necessary to use

    Node *m_next;

to point to the next node in the list instead of
    
    Node m_next;

I understand that it is better to use the pointer version; I&#39;m not going to argue facts, but I don&#39;t know why it&#39;s better. I got a not so clear answer about how the pointer is better for memory allocation, and I was wondering if anyone here could help me understand that better.

Why do linked lists use pointers instead of storing nodes inside of nodes

I cannot figure this out:

    int main() {
        int (*) (int *) = 5;
        return 0;
    }

The above assignment compiles with g++ c++11. I know that `int (*) (int *)` is a pointer to a function that accepts an `(int *)` as argument and returns an int, but I do not understand how you could equate it to 5. At first I thought it is a function that constantly returns 5 (from my recent learning in F#, probably, haha), then I thought, briefly, that the function pointer points to memory location 5, but that does not work, clearly, and neither does hex values.

Thinking that it could be because the function returns an int, and that assigning an int is ok (somehow), I also tried this:

    int * (*) (int *) = my_ptr

where `my_ptr` is of type `int *`, the same type as this second function pointer, as in the first case with type int. This does not compile. Assigning 5, or any int value, instead of `my_ptr`, doesn&#39;t compile for this function pointer either.

So what does the assignment mean?

**Update 1**

We have confirmation that it is a bug, as shown in the best answer. However, it is still not known what actually *happens* to the value that you assign to the function pointer, or what happens with the assignment. Any (good) explanations on that would be very much appreciated! Please refer to the edits below for more clarity on the problem.

**Edit 1**

I am using gcc version 4.8.2 (in Ubuntu 4.8.2)

**Edit 2**

Actually, equating it to anything works on my compiler. Even equating it to a std::string variable, or a function name that returns a double, works.

**Edit 2.1**

Interestingly, making it a function pointer to any function that returns a data type that is not a pointer, will let it compile, such as

    std::string (*) () = 5.6;

But as soon as the function pointer is to a function that returns some pointer, it does not compile, such as with

    some_data_type ** (*) () = any_value;

Meaning of int (*) (int *) = 5 (or any integer value)

A number of compilers provide 128-bit integer types, but none of the ones I&#39;ve used provide the typedefs `int128_t`. Why?

As far as I recall, the standard

   * Reserves `int128_t` for this purpose
   * Encourages implementations that provide such a type to provide the typedef
   * Mandates that such implementations provide an `intmax_t` of at least 128 bits

(and, I do not believe I&#39;ve used an implementation that actually conforms to that last point)

Why isn&#39;t there int128_t?

I have the following Java code with several big arrays which never change their size. It runs in 1100 ms on my computer.

I implemented the same code in C++ and used `std::vector`.

The time of the C++ implementation which runs the exact same code is 8800 ms on my computer. What did I do wrong, so that it runs this slowly?

Basically the code does the following:

    for (int i = 0; i &lt; numberOfCells; ++i) {
            h[i] =  h[i] + 1;
            floodedCells[i] =  !floodedCells[i];
            floodedCellsTimeInterval[i] =  !floodedCellsTimeInterval[i];
            qInflow[i] =  qInflow[i] + 1;
    }

It iterates through different arrays with a size of around 20000.

You can find both implementations under the following links:

- Java: https://ideone.com/R8KqjT
- C++: https://ideone.com/Lu7RpE

(On ideone I could only run the loop 400 times instead of 2000 times because of the time limitation. But even here there is a difference of three times)

Java 8 times faster with arrays than std::vector in C++. What did I do wrong?

For example a declaration such as that:

    int (x) = 0;

Or even that:

    int (((x))) = 0;


I stumbled upon this because in my code I happened to have a fragment similar to the following one:

    struct B
    {
    };
    
    struct C
    {
      C (B *) {}
      void f () {};
    };
    
    int main()
    {
      B *y;
      C (y);
    }

Obviously I wanted to construct object `C` which then would do something useful in its destructor. However as it happens compiler treats `C (y);` as a declaration of variable `y` with type `C` and thus it prints an error about `y` redefinition. Interesting thing is that if I write it as `C (y).f ()` or as something like `C (static_cast&lt;B*&gt; (y))` it will compile as intended. The best modern workaround is to use `{}` in constructor call, of course.

So as I figured out after that, it&#39;s possible to declare variables like `int (x) = 0;` or even `int (((x))) = 0;` but I&#39;ve never seen anyone actually using declarations like this. So I&#39;m interested -what&#39;s the purpose of such possibility because for now I see that it only creates the case similar to the notorious &quot;most vexing parse&quot; and doesn&#39;t add anything useful?



Why does C++ allow us to surround the variable name in parentheses when declaring a variable?

I need to play back a custom AVI file that contains a classic video stream, an audio stream **but also a custom data stream**.

The custom stream contains data that is visualized by some custom widgets; those widgets only need that each *custom frame* is written in a buffer at the proper time.

Our application is based on Qt, and already uses `QMediaPlayer`/`QVideoWidget` to play traditional videos, but the additional custom stream makes things more complicated, because AFAIK `QMediaPlayer` only plays the video/audio and ignores everything else.

I would like to avoid to reinvent the entire `qt-multimedia`, but I am not sure how to make the best out of the available Qt classes.

----------

My ideas so far are:
 
 1. **Write a custom media player** class that demuxes and decodes the video using `ffmpeg`, implements the timing, uses `QAudioOutput` for playing the audio, produces a stream of `QVideoFrame`s to be played on the video and write the custom data to some buffer for visualization.

 **The problem**: In order to avoid writing the code to rescale/convert the video frames, I would like to reuse `QVideoWidget`, but it seems to work only with the &quot;real&quot; `QMediaPlayer`.

 2. **Demux the input file and feed `QMediaPlayer` with the AV streams.** 
Demux the input with `ffmpeg` (possibly leaving the decoding to the Qt backend), have one `QIODevice` to retrieve only the video/audio streams from the input file and another one to retrieve the data stream. Play the video/audio with `QMediaPlayer`.

                      +-------+                          
                      | QFile |                          
                      +---^---+                          
                          |                              
                       inherits                          
                          |                              
                +--------------------+
                |    MyAviDemuxer    |
                |                    |
                |  holds a queue of  |
                |  demuxed packets   |
                +--------------------+
                |                    |
          readDataPacket      readVideoPacket
                |                    |
        +-------v--------+  +--------v-----------+            +-----------+
        | MyCustomReader |  | MyVideoAudioStream +--inherits--&gt; QIODevice |
        +----------------+  +--------+-----------+            +-----------+
                                     |       
                                  setMedia                  
                                     |                  
                             +-------v-------+           
                             | QMediaPlayer  |           
                             +---------------+           


 
    **The problem**: synchronize the timing of the data stream with `QMediaPlayer`, handle headers and metadata correctly.


----------
 
I am slightly inclined to option 1, just because it gives me more control, but I am wondering if I missed an easier solution (even Windows-only).

Playing a custom avi data stream using QtMultimedia

How to configure CLion IDE for Qt Framework?
Is this IDE compatible with Qt, or are there other IDEs compatible with Qt?

I just want to try to use something else than Qt Creator.

How to configure CLion IDE for Qt Framework?

I would like to create a custom widget in Qt with the following features:

 - It is a container
 - It may be populated with any Qt layout
 - It may be inside any Qt layout
 - A button allows to collapse/fold vertically the content, so only the button is visible, all the contained layout is invisible.
 - The previous button allows to expand/unfold it again to the size of the layout content.
 - The expanding/collapsing is based on sizes (not on show/hide) to allows animation.
 - Usable in QDesigner

To provide an idea, here is an image of a similar widget (not Qt):
[![enter image description here][1]][1]


  [1]: http://i.stack.imgur.com/KsVwP.png

I already have a frame that work correctly and is exposed in QDesigner. I need now to make it to extend/collapse, which does not seem so simple.

I tried to play with resize(), sizePolicy(), sizeHint() but that does not work:
When the frame is collapsed I got following values:

    sizeHint: (500,20)
    size    : (500,20)
    closestAcceptableSize: (518,150)
    Painted size: (518, 150)

QLayout::closestAcceptableSize is not part of the widget so I cannot change it.

**Any hint or/and code snippet to achieve that?**

EDITED:
Here a simple example. I removed all except necessary. 

main.cpp example

    #include &lt;QWidget&gt;
    #include &lt;QPushButton&gt;
    #include &lt;QVBoxLayout&gt;
    
    #include &quot;section.hpp&quot;
    
    
    using namespace myWidgets;
    int main(int argc, char *argv[])
    {
    	QApplication a(argc, argv);
    
    
    	// Create the main Window
    	QWidget window;
    	window.resize(500,500);
    	window.setStyleSheet(&quot;QPushButton:{background-color:rgba(128,128,128,192);}&quot;);
    
    	// Create the main window layout
    	QVBoxLayout topLayout(&amp;window);
    	QWidget *w1 = new QWidget();
    	w1-&gt;setStyleSheet(&quot;background-color:rgba(128,128,128,192);&quot;);
    	topLayout.addWidget(w1);
    
    	Section section(&amp;window);
    	topLayout.addWidget(&amp;section);
    
    	QVBoxLayout inLayout(&amp;section);
    	QPushButton *button = new QPushButton();
    	button-&gt;setMinimumHeight(100);
    	inLayout.addWidget(button);
    
    	QWidget *w2 = new QWidget();
    	w2-&gt;setStyleSheet(&quot;background-color:rgba(128,128,128,192);&quot;);
    	topLayout.addWidget(w2);
    
    
    
    	window.show();
    
    	return a.exec();
    }

Section.hpp

    #ifndef SECTION_HPP
    #define SECTION_HPP
    
    #include &lt;QPushButton&gt; //for the expand/collapse button
    #include &lt;QtDesigner/QDesignerExportWidget&gt;
    #include &lt;QLayout&gt;
    #include &lt;QPainter&gt;
    #include &lt;QPaintEvent&gt;
    #include &lt;QDebug&gt;
    
    
    // Compatibility for noexcept, not supported in vsc++
    #ifdef _MSC_VER
    #define noexcept throw()
    #endif
    
    #if defined SECTION_BUILD
    	#define SECTION_BUILD_DLL_SPEC Q_DECL_EXPORT
    #elif defined SECTION_EXEC
    	#define SECTION_BUILD_DLL_SPEC
    #else
    	#define SECTION_BUILD_DLL_SPEC Q_DECL_IMPORT
    #endif
    
    namespace myWidgets
    {
    
    class SECTION_BUILD_DLL_SPEC Section : public QWidget
    {
    	Q_OBJECT
    
    	Q_PROPERTY( bool is_expanded MEMBER isExpanded)
    
    public:
    	// Constructor, standard
    	explicit Section( QWidget *parent=0 ): QWidget(parent),
    		expandButton(this)
    	{
    		expandButton.resize(20,20);
    		expandButton.move(0,0);
    		expandButton.connect(&amp;expandButton, &amp;QPushButton::clicked,
    							 this, &amp;Section::expandCollapseEvent);
    
    		QMargins m= contentsMargins();
    		m.setTop(m.top()+25);
    		setContentsMargins(m);
    		//setSizePolicy(sizePolicy().horizontalPolicy(), QSizePolicy::Minimum);
    
    	}
    
    	virtual void expand( bool expanding ) noexcept
    	{
    		resize(sizeHint());
    		isExpanded = expanding;
    		updateGeometry();
    
    qDebug() &lt;&lt; (isExpanded? &quot;expanded&quot;:&quot;collapsed&quot;) &lt;&lt; sizeHint() &lt;&lt; QWidget::size() &lt;&lt;
    			parentWidget()-&gt;layout()-&gt;closestAcceptableSize(this, size());
    	}
    
    	virtual QSize sizeHint() const noexcept override
    	{
    		if (isExpanded) return QSize(layout()-&gt;contentsRect().width(),
    									 layout()-&gt;contentsRect().height());
    		else return QSize(layout()-&gt;contentsRect().width(), 20);
    	}
    
    	// Implement custom appearance
    	virtual void paintEvent(QPaintEvent *e) noexcept override
    	{
    		(void) e; //TODO: remove
    		QPainter p(this);
    		p.setClipRect(e-&gt;rect());
    		p.setRenderHint(QPainter::Antialiasing );
    		p.fillRect(e-&gt;rect(), QColor(0,0,255,128));
    	}
    
    protected:
    
    	// on click of the expandButton, collapse/expand this widget
    	virtual void expandCollapseEvent() noexcept
    	{
    		expand(!isExpanded);
    	}
    
    
    	bool isExpanded = true; //whenever the section is collapsed(false) or expanded(true)
    	QPushButton expandButton; //the expanding/collapsing button
    };
    
    }
    
    
    #endif // SECTION_HPP

How to make an expandable/collapsable section widget in Qt

I&#39;m trying to read NFC tags on my Android phone using the NFC module of Qt.

According to this [page][1], Qt will support NFC on Android starting from version 5.6. This version hasn&#39;t been released yet, so I built it from source, following the instructions on this [page][2], and installed it in Qt creator.

First step is to get the tag/card detection working and I&#39;m stuck there. My test application instantiates a `QNearFieldManager`, checks if NFC is available and connects slots to the signals `targetDetected` and `targetLost`.
The `QNearFieldManager::isAvailable` method reports that NFC is available (with Qt 5.5 it did not), but the signals `targetDetected`/`targetLost` are never fired.

Below is the code of my test application:

    #include &lt;QLabel&gt;
    #include &lt;QVBoxLayout&gt;
    
    #include &lt;QNearFieldManager&gt;
    #include &lt;QNearFieldTarget&gt;
    
    #include &lt;QDebug&gt;
    
    #include &quot;window.h&quot;
    
    Window::Window(QWidget *parent)
    : QWidget(parent)
    {
        nfcLabel_ = new QLabel(this);
    
        QVBoxLayout *mainLayout = new QVBoxLayout;
        mainLayout-&gt;addWidget(nfcLabel_, 1);
    
        setLayout(mainLayout);
    
        setSizePolicy(QSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed));
    
        setWindowTitle(tr(&quot;NFC Test&quot;));
    
        nfc_ = new QNearFieldManager(this);
        if (nfc_-&gt;isAvailable()) {
            nfcLabel_-&gt;setText(&quot;NFC available&quot;);
        } else {
            nfcLabel_-&gt;setText(&quot;NFC not available&quot;);
            qWarning() &lt;&lt; &quot;NFC not available&quot;;
        }

        nfc_-&gt;setTargetAccessModes(QNearFieldManager::NdefReadTargetAccess); // doesn&#39;t help
    
        nfc_-&gt;registerNdefMessageHandler(this, SLOT(handleNdefMessage(QNdefMessage,QNearFieldTarget*))); // doesn&#39;t help
    
        connect(nfc_, SIGNAL(targetDetected(QNearFieldTarget*)), this, SLOT(targetDetected(QNearFieldTarget*)));
        connect(nfc_, SIGNAL(targetLost(QNearFieldTarget*)), this, SLOT(targetLost(QNearFieldTarget*)));
    
        if (!nfc_-&gt;startTargetDetection()) {
            qWarning() &lt;&lt; &quot;NFC target detection could not be started&quot;;
        }
    }
    
    Window::~Window()
    {
        nfc_-&gt;stopTargetDetection();
    }
    
    void Window::targetDetected(QNearFieldTarget * /*target*/)
    {
        nfcLabel_-&gt;setText(&quot;Target detected&quot;);
    }
    
    void Window::targetLost(QNearFieldTarget *target)
    {
        nfcLabel_-&gt;setText(&quot;Target lost&quot;);
        target-&gt;deleteLater();
    }
    
    void Window::handleNdefMessage(const QNdefMessage &amp;/*message*/, QNearFieldTarget */*target*/)
    {
        qDebug() &lt;&lt; &quot;Ndef Message&quot;;
    }
    

I must be missing something...

**UPDATE 1**

It appears that the AndroidManifest.xml file needs to be modified. I tried different things, but none seem to produce the desired effect. I can only get the `targetDetected` and `targetLost` events to fire when the manifest defines an intent-filter like this:

    &lt;intent-filter&gt;
        &lt;action android:name=&quot;android.nfc.action.TAG_DISCOVERED&quot;/&gt;
        &lt;category android:name=&quot;android.intent.category.DEFAULT&quot;/&gt;
    &lt;/intent-filter&gt;
    
However, this also causes the app to be started each time a target is scanned, even if the app is already running. What I need is to start the app and then wait for a target to be scanned. How can I accomplish this?

**UPDATE 2**

Below is the full AndroidManifest.xml file that I tried.

    &lt;?xml version=&quot;1.0&quot;?&gt;
    &lt;manifest package=&quot;org.qtproject.example&quot; xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot; android:versionName=&quot;1.0&quot; android:versionCode=&quot;1&quot; android:installLocation=&quot;auto&quot;&gt;
        &lt;application android:hardwareAccelerated=&quot;true&quot; android:name=&quot;org.qtproject.qt5.android.bindings.QtApplication&quot; android:label=&quot;-- %%INSERT_APP_NAME%% --&quot; android:theme=&quot;@android:style/Theme.Holo&quot;&gt;
        &lt;activity android:configChanges=&quot;orientation|uiMode|screenLayout|screenSize|smallestScreenSize|layoutDirection|locale|fontScale|keyboard|keyboardHidden|navigation&quot; android:name=&quot;org.qtproject.qt5.android.bindings.QtActivity&quot; android:label=&quot;-- %%INSERT_APP_NAME%% --&quot; android:screenOrientation=&quot;unspecified&quot; android:launchMode=&quot;singleTop&quot;&gt;
            &lt;intent-filter&gt;
            &lt;action android:name=&quot;android.intent.action.MAIN&quot;/&gt;
            &lt;category android:name=&quot;android.intent.category.LAUNCHER&quot;/&gt;
            &lt;/intent-filter&gt;
    
            &lt;!-- Without this, the targetDetected/targetLost signals aren&#39;t fired --&gt;
            &lt;intent-filter&gt;
            &lt;action android:name=&quot;android.nfc.action.TAG_DISCOVERED&quot;/&gt;
            &lt;category android:name=&quot;android.intent.category.DEFAULT&quot;/&gt;
            &lt;/intent-filter&gt;
    
            &lt;meta-data android:name=&quot;android.app.lib_name&quot; android:value=&quot;-- %%INSERT_APP_LIB_NAME%% --&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.qt_sources_resource_id&quot; android:resource=&quot;@array/qt_sources&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.repository&quot; android:value=&quot;default&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.qt_libs_resource_id&quot; android:resource=&quot;@array/qt_libs&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.bundled_libs_resource_id&quot; android:resource=&quot;@array/bundled_libs&quot;/&gt;
            &lt;!-- Deploy Qt libs as part of package --&gt;
            &lt;meta-data android:name=&quot;android.app.bundle_local_qt_libs&quot; android:value=&quot;-- %%BUNDLE_LOCAL_QT_LIBS%% --&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.bundled_in_lib_resource_id&quot; android:resource=&quot;@array/bundled_in_lib&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.bundled_in_assets_resource_id&quot; android:resource=&quot;@array/bundled_in_assets&quot;/&gt;
            &lt;!-- Run with local libs --&gt;
            &lt;meta-data android:name=&quot;android.app.use_local_qt_libs&quot; android:value=&quot;-- %%USE_LOCAL_QT_LIBS%% --&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.libs_prefix&quot; android:value=&quot;/data/local/tmp/qt/&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.load_local_libs&quot; android:value=&quot;-- %%INSERT_LOCAL_LIBS%% --&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.load_local_jars&quot; android:value=&quot;-- %%INSERT_LOCAL_JARS%% --&quot;/&gt;
            &lt;meta-data android:name=&quot;android.app.static_init_classes&quot; android:value=&quot;-- %%INSERT_INIT_CLASSES%% --&quot;/&gt;
            &lt;!--  Messages maps --&gt;
            &lt;meta-data android:value=&quot;@string/ministro_not_found_msg&quot; android:name=&quot;android.app.ministro_not_found_msg&quot;/&gt;
            &lt;meta-data android:value=&quot;@string/ministro_needed_msg&quot; android:name=&quot;android.app.ministro_needed_msg&quot;/&gt;
            &lt;meta-data android:value=&quot;@string/fatal_error_msg&quot; android:name=&quot;android.app.fatal_error_msg&quot;/&gt;
            &lt;!--  Messages maps --&gt;
    
            &lt;!-- Splash screen --&gt;
            &lt;!--
            &lt;meta-data android:name=&quot;android.app.splash_screen_drawable&quot; android:resource=&quot;@drawable/logo&quot;/&gt;
            --&gt;
            &lt;!-- Splash screen --&gt;
    
            &lt;!-- Background running --&gt;
            &lt;!-- Warning: changing this value to true may cause unexpected crashes if the
                  application still try to draw after
                  &quot;applicationStateChanged(Qt::ApplicationSuspended)&quot;
                  signal is sent! --&gt;
            &lt;meta-data android:name=&quot;android.app.background_running&quot; android:value=&quot;false&quot;/&gt;
            &lt;!-- Background running --&gt;
        &lt;/activity&gt;
        &lt;/application&gt;
        &lt;uses-sdk android:minSdkVersion=&quot;10&quot; android:targetSdkVersion=&quot;14&quot;/&gt;
        &lt;supports-screens android:largeScreens=&quot;true&quot; android:normalScreens=&quot;true&quot; android:anyDensity=&quot;true&quot; android:smallScreens=&quot;true&quot;/&gt;
        &lt;uses-feature android:name=&quot;android.hardware.nfc&quot; android:required=&quot;true&quot;/&gt;
        &lt;uses-permission android:name=&quot;android.permission.NFC&quot;/&gt;
    &lt;/manifest&gt;
    

  [1]: https://wiki.qt.io/New_Features_in_Qt_5.6
  [2]: http://wiki.qt.io/Qt5ForAndroidBuilding

How to get NFC working on Android using Qt 5.6

I just installed Qt 5.5 and am using Qt Creator for the first time on OS X.  When I first installed Qt, it gave me an error message &#39;Xcode 5 not installed&#39; which I thought was strange, (I have the Xcode 7 beta), but the install completed successfully anyways.

Now, when I start or open a project, I get the error:

&gt;Project ERROR: Xcode not set up properly. You may need to confirm the license agreement by running /usr/bin/xcodebuild.

When I run `/usr/bin/xcodebuild` in Terminal, I get the following:

&gt;xcode-select: error: tool &#39;xcodebuild&#39; requires Xcode, but active developer directory &#39;/Library/Developer/CommandLineTools&#39; is a command line tools instance

I&#39;m not sure what Xcode has to do with Qt Creator, unless it has something to do with accessing libraries for cross-platform compatibility, but is there a way to fix this issue?

Content Type	Original Author	Original Content on Stackoverflow
Question	sashoalm	View Question on Stackoverflow
Solution 1 - C++	sashoalm	View Answer on Stackoverflow
Solution 2 - C++	Sascha	View Answer on Stackoverflow

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