I am a beginer of QT, I tried to add an action to a toolbar and I wrote as follows:
toolbar->addAction(QIcon("/icons/new.png"), "New File");
However, the image can not be loaded. Is that related to my debug path? I can see the button, but no images.
those codes are in test.cpp and my icons folder is in the same path with test.cpp
Paths are interesting.
If you are on linux, you just specified that the root of the drive has a folder called icons, and inside it it has a file called new.png.
If you were using that kind of a path on a website, it would chop off everything to the left besides the domain and subdomain names.
example.com/path/to/some/folder/index.html, processes link to /icons/new.png, and you end up at: example.com/icons/new.png.
The best way to handle paths correctly is to use common notations for relative paths (in most cases... in some cases, absolute paths make sense).
./ means the folder that I am currently in aka the working directory.
../ means the folder above me.
A leading / means the highest folder possible or the root folder, on Unix systems. It is also akin to giving an absolute path for a file.
No leading . or .. or / means the same as ./, or from the working directory.
And there are even more rules about this. See the wiki entry:
http://en.wikipedia.org/wiki/Path_(computing)
In Qt there is also the resource system, that embeds files into the exe itself and can give you a harder-to-change image or graphic on your program.
The notation to access this is:
:/ means the root of the qresource system.
And if you do decide there is a reason to use a backslash, be sure to escape it. Normally Qt will take any input with backslashes and convert it for you on the fly to forward slashes.
So to double check that the file is there, use QFile file("icons/new.png"); followed by if(!file.exists()){ qDebug() << "File is not found!" << file.fileName(); }
Sometimes I find it helpful to see where my program is when this is happening. Either using system("dir"); or qDebug() << QDir::currentPath();
http://doc.qt.io/qt-5.5/qdir.html#currentPath
You can also see what your initial working directory is by looking at your project properties for the project in Qt Creator under:
Projects (tab) > Run (tab) > Run > Working directory:
Usually it is the root of where your source code is and where your .pro file is located.
Hope that helps.
If you are using Qt resources then you need a colon:
toolbar->addAction(QIcon(":/icons/new.png"), "New File");`
if you don't use resources then yuo should use relative path. Remember that Qt Creator uses by default "build in different place" so you must make sure that icon is deployed in respective directory.
Related
I'm using Qt Creator on Windows and trying to add an image to an icon.
The only way I can get it to work is by specifying the full path:
QPixmap newIcon("C:/Users/slipn/Documents/qt/projetos/exemplo/new.png");
newToolBarAction = toolbar->addAction(QIcon(newIcon), "New File");
I tried adding to the project as shown below:
The image and the code files are in the same directory. I have no clue of what path I should use to make it work. Any hints?
The problem you need to solve, is that your source path and the path where you build or maybe later even install your application are not the same. You need to bundle your image resource with your application, either by copying & installing it to your build/install, or by including it directly in your application binary.
The latter is your easiest bet with qmake. Installing files with qmake is (relatively) easy, but making your build result work without a separate make install step is a different thing.
Your easiest bet to solve both "running your build result directly" and "running the installed application" is to use the Qt Resource System.
Create a .qrc file with File > New File > Files and Classes > Qt > Qt Resource File, add a "prefix" (some name), add your image file there, and then use QPixmap newIcon(":/yourprefix/new.png") to access it in your application.
Im getting two different paths when i run the same build within Qt Creator and when I double click on it from the Finder on a Mac.
Here is my code:
QDir dir = QDir::currentPath();
dir.cdUp();
dir.cdUp();
dir.cdUp();
QString rootPath = dir.absolutePath();
When I run it (debug) mode in Qt Creator my path is:
/Users/myuser/Projects/AppName/build/mac
When I double click on the file that is located on
/Users/myyser/Projects/AppName/build/mac from finder it returns
/ only.
Why would I get two different paths?
Version: Qt5.2.1
Update
Seems like its a bug from reading the following URLhttp://qt-project.org/forums/viewthread/34019
Why would I get two different paths?
As they write in the thread you linked, QDir::currentPath() does not necessarily returns the application directory. It will return the path from wherever the application is run, which will be different than the application directory when running the application from the command line, or even from "start menu" alike places and so on.
If you wish to deal with the application directory to navigate from there, you would need to use the following method instead:
QString QCoreApplication::applicationDirPath() [static]
Returns the directory that contains the application executable.
For example, if you have installed Qt in the C:\Qt directory, and you run the regexp example, this function will return "C:/Qt/examples/tools/regexp".
On Mac OS X this will point to the directory actually containing the executable, which may be inside of an application bundle (if the application is bundled).
The last sentence even clarifies the Mac OS X case.
The current directory can be anything, it solely depends on how your process is launched. What you've shown so far is that Qt Creator and Finder start the process with different current directory, that's all.
The only use for currentPath without setting it first, that I can think of, is in command line / console applications. Why do you think you need to use it? To what end?
I've been using windows in a class I've been taking but I am trying to run a basic code to figure out how to open/close/input/output from files on Xcode and the code I usually use on visual studios isn't working any idea why? thanks!
#include <string>
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
ifstream fin;
ofstream fout;
string input;
fin.open("inputFile.txt");
if(fin.fail())
cout << "File failed to open." << endl;
fin >> input;
fout.open("outputFile.txt");
fout << input;
}
Put your .txt files in the same directory where your main.cpp file is (or anywhere you like).
In Xcode go to Product > Scheme > Edit Scheme > Run (on the left) > Options (middle top)
Down under Options for "Working Directory" check “Use custom working directory” and set it to the directory where you .txt files are located.
To work with the files, you will have to specify just file names, e.g. in_file.open("inputFile.txt"); no path is necessary.
Here's a completely different approach: Have Xcode copy the input file for you.
Select your project in Xcode
Select Build Phases
Click the '+' button to create a new Build Phase
Select New Copy Files Build Phase
Select Products Directory
Click the '+' button to add your file
Click Add Other
Select your input file and click Open
Check the Copy items… checkbox and click Finish
Now every time you build your project, the input file will be copied to the same folder as the executable no matter where it is built. Of course, to see the output file, you'll still need to find the executable in Finder.
The answers don't really explain the problem so I thought I'd do that.
When you pass a relative path like "inputFile.txt" to file APIs, it's treated as relative to the working directory when the program is executed. This is the same as the 'working directory' when you use cmd.exe or Terminal.app or command lines in general. The Unix command pwd ("print working directory") displays the current working directory. On Windows running the command cd with no arguments performs the same function. (On Unix running cd with no arguments will change the working directory to the user's home directory.)
When you run a program from the command line, the command line shell sets the program's working directory. When you run a program from within an IDE, the IDE sets the working directory. Since, unlike on a command line, there's no obvious answer for what the IDE should set as the working directory, Visual Studio and Xcode set the working directory to different locations by default: Visual Studio sets the working directory to $(ProjectDir), the directory containing the Visual Studio project file; Xcode sets the working directory to the build products directory, i.e. the location the executable was written to.
Some possible solutions to your problem are:
Do not use a relative path, and therefore don't depend on the working directory. This isn't much help in making the program more portable, because the absolute paths will also differ between platforms, and so you will still have to 'configure' the program for each platform. In fact using an absolute path is worse, because it means your source code must differ, whereas it would be better to keep that difference confined to each platform's build configuration.
Configure the IDE to use your desired working directory. Visual Studio can be configured by right clicking the project, selecting Configuration Properties > Debugging > Working Directory, and setting the working directory to the desired path (potentially using Visual Studio build variables).
nepete's answer describes how to configure the working directly set by Xcode.
Configure the IDE's build process to copy your data files to an appropriate location. In Visual Studio you would do this in a C++ project by configuring the project's Properties > Configuration Properties > Build Events.
SSteve's answer covers how to configure additional build steps in Xcode.
I'm guessing you have inputFile.txt in the folder that contains your source code. That's not going to work. You need to put it in the folder that contains the generated executable. To find that folder, right-click on your app under Products and select Show In Finder.
This image shows what it looks like for a command line program. It also shows the Finder window that was opened. As you can see, it is a different folder than the one containing the source code.
As suggested by nepete, edit the scheme, but use $PROJECT_DIR as the custom working directory. Helps with moving the project around, or working in two different environments (e.g., home and office).
BTW. $PROJECT_DIR is one of the Xcode Environment Variables, and also helps with passing file names as command line arguments to programs (settable under "Arguments" in the scheme).
I've struggled with the same problem today. I wanted to add C code to my Swift project and my file pointer was always NULL.
Unfortunately, in XCode 9 for iOS app, I couldn't change the working directory. Changing Build phases didn't help me either. After 4+ hours of trial and error, that's what I've come up with finally and it works:
when copying files to XCode, I've chosen "Create groups", but I needed to choose "Create folder references":
I created a new objective-c file (.m) and copied all my C code there.
I left untouched .h files (XCode generated bridging header and my own .h file with public functions declaration). Now my project structure looked like this:
In my dict.m file in place of previous plain c fopen part:
FILE *dic = fopen("dictionary.txt", "r");
I added obj-C code:
NSString *filePath = [[NSBundle mainBundle] pathForResource:#"dictionary" ofType:#"txt"];
FILE *dic = fopen([filePath cStringUsingEncoding: NSUTF8StringEncoding], "r");
And it works now without any problem! It's just amazing!
ps I decided to write this answer in case it will help someone like me and will save them some time. If you know how to change working directory in XCode 9 for iOS, please, leave me a comment - now I am really curious why I can't find it.
I am writing a simple C++ helpertool for a popular game (League of Legends), targeted at windows users.
I wish to allow the user to auto restart games which crash. This can be done by starting 'leagueoflegends.exe'. I want to autodetect the location of the executable and this is where I have issues.
The exe is located at:
*GAME_FOLDER*\RADS\solutions\lol_game_client_sln\releases\x.x.x.xx\leagueoflegends.exe
I use a registry entry to get the game folder, ie: C:\leagueoflegends\
However there is a folder that changed with every update in the form of x.x.x.xx where the x are digits (numbers) reflecting the versions. There is always 1 folder in the releases folder.
I figured I need to use REGEXP but I didn't have much luck.
This is the regexp I made:
^[0-9]\.[0-9]\.[0-9]\.[0-9][0-9]$
This is what I used to get the name of the dir using cmd
dir /B | findstr /R " ^[0-9]\.[0-9]\.[0-9]\.[0-9][0-9]$"
However I cant seem to be able to run the executable no matter what I do. Its not like linux where I can manipulate filters and pipes. Any help with a one liner to run the exe or methods of obtaining the folder name (without using a system call?) would be appreciated. Once I can get the folder name in a variable then it becomes easy.
Thanks in advance!
I have recently created a program using C++ and the SDL library. Originally, all the images and DLLs were in the same folder as the main application. I wanted to make the main application easier to find, so I instead moved all the images into their own folder and modified my source code to find them in the correct folder. So far, so good. The main application still remains in the same folder as the DLLs.
I created a shortcut to the main application and put that it's own folder. I changed the target to %windir%\system32\cmd.exe /q/c start "" ""%SystemRoot%\explorer.exe %UserProfile%\Desktop\Cupcake Corner Build 2.0 (exe test)\dependecies\Cupcake Corner.exe" in an attempt to make a universal shortcut, so that the shortcut would work for any user I send the files to.
After all said and done, I've ran into a problem. If I open the main application itself, it will load the images and work perfectly. If I try to the main application via its shortcut, the window will open correctly and display the correct title, although none of the images will load. I tried moving some files around to see if the shortcut would see them if I put the resource folder elsewhere, but so far no luck.
images here -> C:\Users\Admin\Desktop\Cupcake Corner Build 2.0\dependecies\resources
main app/dlls here -> C:\Users\Admin\Desktop\Cupcake Corner Build 2.0\dependecies\
shortcut here -> C:\Users\Admin\Desktop\Cupcake Corner Build 2.0\
I am using Microsoft Visual Studio Express 2010. I think it has something to do with the way I have my project directory set in project options, but I'm honestly baffled at this point. Can anyone point me in the right direction?
Generally, when dealing with files in an application (that the application knows internally, at least), you will want to have absolute paths.
The best way to solve this is by having a (set of) function(s) that add the absolute path (found by GetModuleFilename(0, ...) or from some configuration for example in the registry)
std::string myfiles_root_path = FindMyFilesRootPath();
std::string MakeFullPath(const std::string &filename)
{
return myfiles_root_path + filename;
}
The function FindMyFilesRootPath() uses one of the methods above to find the appropriate path, and filename is the name of a file local to your application.