    QProcess process;
    process.start(&quot;gedit&quot;, QStringList() &lt;&lt; docPath);

the same as above

    QProcess process;
    process.start(&quot;gedit&quot;, QStringList() &lt;&lt; &quot;/home/oDx/Documents/a.txt&quot;);

Also, read [this][1].


  [1]: http://doc.qt.io/qt-5/qprocess.html

[QProcess::execute()][1] may be helpful:

    QProcess::execute(&quot;gedit /home/oDx/Documents/a.txt&quot;));


  [1]: https://doc.qt.io/qt-5/qprocess.html#execute-1

During a refactor of an iOS project, I ran into this bear of a bug. During the linking phase, I get this message:

&gt;ld: duplicate symbol _OBJC_IVAR_$_TinCanViewController.currentViewController in /path/to/TinCanViewController-E98A666B7AF2673A.o and /path/to/TinCanViewController-E98A666B7AF2673A.o

As far as I can tell, it looks like it claims `TinCanViewController-E98A666B7AF2673A.o` is declaring the specified symbol twice; both paths are pointing to the exact same .o file. I ran `nm` on that specific file, and it only included that symbol once: 

&gt; 00008150 S _OBJC_IVAR_$_TinCanViewController.currentViewController

I ran `nm` on all the other .o files in the directory to see if they were somehow declaring this symbol, too, but they&#39;re not. This happens to any member I add to the TinCanViewController class - it&#39;s not specific to currentViewController.

I feel like I must be somehow linking against the class twice somehow, but I&#39;ve pretty assiduously gone through and checked all references to this class. In the refactored version, there are basically none. The AppDelegate includes it, but right now it&#39;s basically just a passthrough class that loads another ViewController at the start. No other classes in the project include it.

Any suggestions on what might be causing this or how I might debug it better?


Duplicate symbol issues

When calling `progressDialog = ProgressDialog.show(this, null, null, true);` usually the developers wants to only show the progress indication image, and usually would it expect to be centered within the window (at least from regular UI design point of view).
But the image is too far left, it seems that some padding/margin on the right hand side is still being calculated in for (optional) text on the right, although we&#39;re not passing any text as parameter.
It would just make life little easier for a developer :) So we don&#39;t need to create a custom dialog only in order to have the progress indicator being centered by default.

(I filed this as a feature request at http://code.google.com/p/android/issues/detail?id=9697; please star it if you would also like to see this improved).

Now my questions:

1. How can I easily center the progress image without having to entirely create my own custom alert dialog class? Any parameter I might have overlooked?

2. Furthermore, how to set the background to transparent? 

I&#39;m also wondering about this: 
https://stackoverflow.com/questions/2866141/how-to-put-custom-animation-into-a-progressdialog
I haven&#39;t actually tried it myself yet but if you cannot create custom animations, it means if you want a kind of animated progress indicator, you always need to extend the ProgressDialog class?
Looking at the ProgressDialog class though, I don&#39;t find anything other than regular drawables though ([ProgressDialog.java][3]), they&#39;re not using AnimatedDrawable there.


  [1]: http://img340.imageshack.us/img340/2218/progressindicator.png
  [2]: http://img59.imageshack.us/img59/517/newsrobprogress.png
  [3]: http://www.netmite.com/android/mydroid/frameworks/base/core/java/android/app/ProgressDialog.java

How to center progress indicator in ProgressDialog easily (when no title/text passed along)

I have to run a system command in Qt. 
but I have to give an argument for that command.

for example opening gedit with a text file.
like &quot;gedit /home/oDx/Documents/a.txt&quot;

but the path &quot;/home/oDx/Documents/a.txt&quot; will be in a variable like &quot;docPath&quot;.
so how can i do it!?


How to run a system command in Qt?

I have to run a system command in Qt.
but I have to give an argument for that command.
for example opening gedit with a text file.
like "gedit /home/oDx/Documents/a.txt"
but the path "/home/oDx/Documents/a.txt" will be in a variable like "docPath".
so how can i do it!?

I am using Qt 4.6.0 (32 bit) under Windows 7 Ultimate. Consider the following `QThread`:

##Interface

    class ResultThread : public QThread
    {
	Q_OBJECT

        QString _post_data;
        QNetworkAccessManager _net_acc_mgr;

    signals:
        void onFinished(QNetworkReply* net_reply);

    private slots:
        void onReplyFinished(QNetworkReply* net_reply);

    public:
        ResultThread();

        void run();
        void setPostData(const QString&amp; post_data);
    };

##Implementation

    ResultThread::ResultThread() : _net_acc_mgr(this)
    {
        connect(&amp;_net_acc_mgr, SIGNAL(finished(QNetworkReply*)),
                this, SLOT(onReplyFinished(QNetworkReply*)));
    }

    void ResultThread::onReplyFinished(QNetworkReply* net_reply)
    {
        emit onFinished(net_reply);
    }

    void ResultThread::setPostData(const QString&amp; post_data)
    {
        _post_data = post_data;
    }

    void ResultThread::run()
    {
        _net_acc_mgr.post(QNetworkRequest(QUrl(&quot;http://[omitted]&quot;)),
                          QByteArray(_post_data.toStdString().c_str()));
    }

Whenever `_net_acc_mgr.post()` is executed in `ResultThread::run()`, I got the following Application Output in Qt Creator:

&gt; QObject: Cannot create children for a parent that is in a different thread.

&gt; (Parent is QNetworkAccessManager(0x22fe58), parent&#39;s thread is QThread(0x9284190), current thread is ResultThread(0x22fe48)

What does this mean? How to solve it?

QObject: Cannot create children for a parent that is in a different thread

How do I add a define with qmake WITH a value:

For example, this does not work (as I expected) in my .pro file:

    DEFINES += WINVER 0x0500

nor

    DEFINES += &quot;WINVER 0x0500&quot;

How do I define WINVER as 0x0500 before anything starts compiling so it&#39;s definition is not affected in any way by compilation or include order?

Add a define to qmake WITH a value?

I have a Qt GUI application running on Windows that allows command-line options to be passed and under some circumstances I want to output a message to the console and then quit, for example:

    int main(int argc, char *argv[])
    {
      QApplication a(argc, argv);
    
      if (someCommandLineParam)
      {
        std::cout &lt;&lt; &quot;Hello, world!&quot;;
        return 0;
      }
    
      MainWindow w;
      w.show();
    
      return a.exec();
    }

However, the console messages do not appear when I run the app from a command-prompt.  Does anyone know how I can get this to work?


Console output in a Qt GUI app?

Is it possible to open a folder in Windows Explorer/OS X Finder and then select/highlight one file in that folder, and do it in a cross platform way? Right now, I do something like

    QDesktopServices::openUrl( QUrl::fromLocalFile( path ) );

where `path` is a full path to folder I want to open. Obviously, this will just open the folder, and I&#39;ll have to track down the file I need manually. This is a bit of a problem when there are thousands of files in that folder.

If I make it a path to specific file in that folder, then that file is open with default application for that mime type, and that is not what I need. Instead, I need the functionality equivalent to &quot;Reveal in Finder&quot; or &quot;Show in Explorer&quot;.

How to &quot;Reveal in Finder&quot; or &quot;Show in Explorer&quot; with Qt

I&#39;m using the Qt Designer.

I want to create a `QVBoxLayout` which will automatically expand to fill the whole window.

The layout of the `QVBoxLayout` remains fixed.

How can I cause the `QVBoxLayout` to expand and fill the entire window through the designer?

Auto-expanding layout with Qt-Designer

Is there a Linux command to easily find out which partition/mount a directory or file is on? 


(This is probably a RTM question, and I feel guilty for asking it, but somehow, I can&#39;t find a good answer on google just yet..)

How to find out mount/partition a directory or file is on? (Linux Server)

How do I read every line of a file in Python and store each line as an element in a list? 

I want to read the file line by line and append each line to the end of the list.

How to read a file line-by-line into a list?

I&#39;m trying to find a nice way to read a log file in real time using python.  I&#39;d like to process lines from a log file one at a time as it is written.  Somehow I need to keep trying to read the file until it is created and then continue to process lines until I terminate the process.  Is there an appropriate way to do this? Thanks.

Read from a log file as it&#39;s being written using python

Is there an in-built function in Ruby to read the whole file without using any loop? So far, I have only come across methods that read in chunks (line or character).

How to read whole file in Ruby?

I have a text file which contains a time stamp on each line. My goal is to find the time range. All the times are in order so the first line will be the earliest time and the last line will be the latest time. I only need the very first and very last line. What would be the most efficient way to get these lines in python?

Note: These files are relatively large in length, about 1-2 million lines each and I have to do this for several hundred files. 

What is the most efficient way to get first and last line of a text file?

What&#39;s the difference between QMainWindow, QWidget and QDialog?

eg: 

    QFile f(&quot;/home/umanga/Desktop/image.jpg&quot;);

How I get only the filename - &quot;image.jpg&quot;?

Get filename from QFile?

It&#39;s possible to bind more than one signal to one slot (isn&#39;t?). So, is there a way to understand which widget sends the signal? I&#39;m looking for something like `sender` argument of events in .NET

How to get sender widget with a signal/slot mechanism?

(Posting this question for reference purpose, I&#39;ll answer immediately)

How to add header search paths to Xcode?
Especially when including with this syntax:

    include &lt;myheader.h&gt;

1. Adding path globally to all projects like system headers.
2. Adding path to only to a specific project.

Adding system header search path to Xcode

What is the difference between `subprocess.Popen()` and `os.system()`?

Difference between subprocess.Popen and os.system

I was asked this question during an interview. What they wanted to know was when the user calls malloc(4) to allocate 4 bytes of memory how does the operating system (Linux) respond? Which subsystem responds to this system call? 

I told him that malloc() will be serviced by the memory management subsystem. The malloc() implementation will go through the list of free memory(physical memory), we will call it free list, and find an appropriate chunk that is greater than or equal to 4 Bytes. Once it finds such a chunk, it will be deleted from free list and added to a used list. Then that physical memory will be mapped to the process heap vma struct. He didn&#39;t seem to be quite satisfied with this answer.How does the buddy system fit into this? Any help would be greatly appreciated.

what happens in the kernel during malloc?

What&#39;s the difference between system properties [System.getProperties()][1] and environment variables [System.getenv()][2] in a JVM?


  [1]: http://download.oracle.com/javase/6/docs/api/java/lang/System.html#getProperties%28%29
  [2]: http://download.oracle.com/javase/6/docs/api/java/lang/System.html#getenv%28%29

Java system properties and environment variables

I had entered:

    * 22 * * * test &gt; /dev/null
However, I am being notified via email that this is running every minute.
I am confused I guess because I thought this was correct for what I am wanting.


Content Type	Original Author	Original Content on Stackoverflow
Question	defiant	View Question on Stackoverflow
Solution 1 - Qt	mosg	View Answer on Stackoverflow
Solution 2 - Qt	baziorek	View Answer on Stackoverflow

How to run a system command in Qt?

Qt Problem Overview

Qt Solutions

Solution 1 - Qt

Solution 2 - Qt

How to center progress indicator in ProgressDialog easily (when no title/text passed along)

Duplicate symbol issues

Attributions