I need to initialize a qpixmap object with its file directory
It works if I do the following:
image = new QPixmap("C:/Users/Administrator/Desktop/maze/HTetris-build-Desktop_Qt_5_0_1_MinGW_32bit-Debug/untitled/c12.bmp");
and it works with as well:
image = new QPixmap("/Users/Administrator/Desktop/maze/HTetris-build-Desktop_Qt_5_0_1_MinGW_32bit-Debug/untitled/c12.bmp");
But this is just too long and too specific.
I have put c12.bmp in the same file as the project itself. But
image = new QPixmap("c12.bmp");
simply does not work.
Since this project needs to be portal, how can I do!!!!!!!
Thanks guys for help
Consider to put your file into resource file (qrc) or put your file near your executable file, because your "c12.bmp" is searched in runtime and must be in the same with executable directory.
You file must be in the file where your application is executed (runtime directory) that can be different than the directory of the executable.
You can use resource files for the portablity (your pixmap will be "embedded" in your binary).
http://qt-project.org/doc/qt-4.8/resources.html
Related
When I try to load a file by the relative path via QFile, gives file not found.
QFile file(fileName);
So I output the current work folder to find the problem like this:
qDebug()<<QDir(".").absolutePath();
Output: /home/username
qDebug()<<qApp->applicationDirPath();
Output: /home/username/program/testApp
The second one is the right path to the work folder. So I think QFile didn't load the file from the work folder but the Linux user folder ~. Why didn't QFile load the file refer to the work folder?
I guess this may be a bug in Raspberry's QtCreator. Because the QFile load file is working well if run in the console.
Use QStandardPaths to store data to your OS paths, in this way you would refer to consistent set of locations when you retrieve the file.
For instance:
auto path = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
QFile afile;
QString fileName = "/myfile.txt";
path += fileName;
afile.setFileName(path);
Is there any possibility in IAR to add additional project variable like $PROJ_DIR$ to specify my project environment?
I like to keep my project portable and adaptable.
Of course there are, according to the manuals:
Variable / Description
$CONFIG_NAME$ The name of the current build configuration, for example Debug or Release.
$CUR_DIR$ Current directory
$CUR_LINE$ Current line
$DATE$ Today’s date
$EW_DIR$ Top directory of IAR Embedded Workbench, for example c:\program files\iar systems\embedded workbench 6.n
$EXE_DIR$ Directory for executable output
$FILE_BNAME$ Filename without extension
$FILE_BPATH$ Full path without extension
$FILE_DIR$ Directory of active file, no filename
$FILE_FNAME$ Filename of active file without path
$FILE_PATH$ Full path of active file (in Editor, Project, or Message window)
$LIST_DIR$ Directory for list output
$OBJ_DIR$ Directory for object output
$PROJ_DIR$ Project directory
$PROJ_FNAME$ Project filename without path
$PROJ_PATH$ Full path of project file
$TARGET_DIR$ Directory of primary output file
$TARGET_BNAME$ Filename without path of primary output file and without extension
$TARGET_BPATH$ Full path of primary output file without extension
$TARGET_FNAME$ Filename without path of primary output file
$TARGET_PATH$ Full path of primary output file
$TOOLKIT_DIR$ Directory of the active product, for example c:\program files\iar systems\embedded workbench 6.n\arm
$USER_NAME$ Your host login name
$ENVVAR$ The environment variable ENVVAR. Any name within $_ and _$ will
be expanded to that system environment variable.
If you go to Tools > Configure Custom Argument Variables you can add variables that you can address with $VARIABLE_NAME$. Not sure if that's exactly what you were looking for.
As a caution, if you are using IarBuild.exe to build from the command line, the workspace or global values set from "Configure Custom Arguments Variables" are not included in the project files (.ewp) and thus is not expanded by IarBuild.exe at build time. This is not an issue if you only use the IDE to build.
I found a reason for my problem (but it givs another one):
I define a windows "path-variable" like LIB_PATH and put it in the IAR project file with $_LIB_PATH_$.This works as long until i save the IAR-project. Then IAR sets all paths realive to $PROJ_DIR$ :-(
I have built a static Qt library and want to use it deploy my app with a standalone exe. After one day effort, I have known that the qtquick plugin can not be static include into exe.
I need copy some folders in qml folder to my exe directory to let the exe can show GUI.
So I want to know which file my exe need, I deleted files in those folders one by one to get it known. The real needed file is just a plugins.QMLTYPES file and a qmldir file.
And then I found the import path of QQmlApplicationEngine can be changed, I output the QQmlApplicationEngine.importPathList() and one of paths is just the qml folder in Qt installed path. So I think this is the place where Qt get the search path of plugins.QMLTYPES file and qmldir file.
If all I think is correct, I can just copy the folders I need into qrc file and use QQmlApplicationEngine.addImportPath("qrc:/foldersIwant") to let exe can import what it need on runtime. And because qrc is compiled into exe, I can get rid of those folders and let my exe standalone.
But after I do this in my code, app still can not find the files it need even the output of QQmlApplicationEngine.importPathList() has the path I put into and I have also checked my path according to Load qmldir from QRC file.
Here is the code:
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QQmlApplicationEngine engine;
engine.addImportPath(QStringLiteral("qrc:/import/qtquick/"));
qDebug()<<engine.importPathList();
engine.load(QUrl(QStringLiteral("qrc:/qml/main.qml")));
return app.exec();
}
Here is a part of my qrc file
Is there anything wrong in my deductive？
Further research:
I have add
engine.addImportPath(QDir::currentPath() + QDir::separator() + "custom");
and move all folders into custom folders, it can run successfully. And the exe which doesn't have this line can not run with custom folder. So I'm wondering the "search" behavior can not be applied to qrc file ?
Finally, I get the answer. The result shows all my thoughts are correct!
Below is what I had tried and you can just read the end to get the clear steps.
My aim is to compile a standalone qml2 application exe.
In qml1, I can build static Qt library and compile my app with it.
In qml2, the exe can be compiled in same way. But if I run it without Qt-Runtime. It just do not have any window shown on Windows OS (and also show nothing in other OS). I have googled so many informations and found this problem troubled many people since Qt5.0. Now it is Qt5.5, they still haven't repaired it. So I need copy folders in QT_INSTALLED_PREFIX/qml to the root directory of my app to let my app show GUI.
Althrough the problem will be solved in Qt5.6 (https://codereview.qt-project.org/#/c/114835/), I can't wait for so long (Qt5.6 will be released at the end of this year). So I decide to package the files by myself.
And I see this question by chance :Load qmldir from QRC file. It told me that qmldir file can be include into qrc file and the Qml engine can search into those directory. So I think, the QML files can also be included into qrc file.
But the first thing is to find where the qml2 be imported, when I looking into QQmlApplicationEngine's document, I found addImportPath function and I told myself that it must be the key of finding the import path. The document tells me everything:
QStringList QQmlEngine::importPathList()
const Returns the list of
directories where the engine searches for installed modules in a
URL-based directory structure.
For example, if /opt/MyApp/lib/imports is in the path, then QML that
imports com.mycompany.Feature will cause the QQmlEngine to look in
/opt/MyApp/lib/imports/com/mycompany/Feature/ for the components
provided by that module. A qmldir file is required for defining the
type version mapping and possibly QML extensions plugins.
By default, the list contains the directory of the application
executable, paths specified in the QML2_IMPORT_PATH environment
variable, and the builtin Qml2ImportsPath from QLibraryInfo.
After I delete the Qml2ImportsPath in importPathList at runtime, I made a recurrence of the bugs that app do not show any GUI.
And the document of addImportPath tells my that it can accept qrc url. So I add all the files in qml just like the question described above. But I still cannot see any GUI.
After several days of thinking. I found the pic I posted in question do not have qmldir files! That's a bug of Qt Creator. I add files using Add Existing Directory... and set the filter to *, it still cannot include qmldir file. So I add it into qrc file by xml code.
When I think this time it must work, it just gave me nothing. Just when I was going to give up, a thought occurred : it won't waste me more time to check whether qrc:/import/qtquick/ is valid.
The result is false, there must be a mistake in my qrc usage. I change the prefix and save the qrc with Qt Creator. I found the qrc file cannot use the path like D:/Qt/Qt-5.5-static/qml/Qt/labs/folderlistmodel/plugins.qmltypes, it is changed by Qt Creator to Qt/labs/folderlistmodel/plugins.qmltypes. At this time, everything works perfect!
Thanks for you reading my story. Here is a conclusion of steps for solving this problem:
Copy all folders in QT_INSTALLED_PREFIX/qml to your project folder, it is good to put them under a parent folder not the root folder.
Write some code to get all files' relative path except the .lib files and
.prl files.
Create a new .qrc file and include it in .pro file. Include all files into this .qrc file. I wrote a small program to generate the xml.
Add the import path using addImportPath method of QQmlApplicationEngine.
Build and enjoy.
I have a problem regarding exporting my Java project into a jar file.
I have this file (application.properties) which contains some database information and located under the project root directory.
There is no problem when running this project on Eclipse. But after exporting into a jar(Runnable Jar file) file, application.properties will not be included in the packaging and that cause the error.
Any suggestion how to fix this problem?
Do you want to have the application.properties reside outside the jar (for writing), or is it read-only? When outside you can have an initial template file in the jar, and copy it to some location.
//String applicationWorkingDir = System.getProperty("user.dir"); // The current constellation.
String userHomeDir = System.getProperty("user.home");
File myApplicationDataDir = new File(userHomeDir + "/.MyApplication");
myApplicationDataDir.mkdir();
File propertiesFile = new File(myApplicationDataDir, "application.properties");
Also using the Preferences API instead of a properties would be a solution.
I am new to programming. I am creating a small word jumble game to practice qt programming. In this application I am creating a text file (score.txt) to keep score of player. I have done this by:
QFile scoreFile("score.txt");
if (QFile::exists("score.txt"))
{
scoreFile.open(QIODevice::ReadWrite | QIODevice::Text)
// and update the score.
}
else
{
scoreFile.open(QIODevice::ReadWrite | QIODevice::Text);//create score file
//and write the score to it.
}
this code is working good here. Now I am using CMake to build and install generated binary (I am working on Ubuntu) using this code:
#set project name, version and build code here.
install(TARGETS wordJumbleGame DESTINATION bin)
I build project in /home/myname/project/build/
My source code is in /home/myname/project/src/
CMakeLists.txt is in /home/myname/project/CMakeLists.txt
I installed program using make install.
Till here all things working fine. But now problem is that when I run this program (I run it from terminal giving command wordJumbleGame) It creates score.txt in /home/myname/project/build directory. It is not being created in installation dir bin.
So please help me out, what am I doing wrong. And please also tell me how do I make my program to appear in application->game lists so I can run it from there not from command prompt.
Unless you prefix it with a slash (on unix) or a drive path (Windows), QFile's constructor parameter is a relative path - relative to the current working directory. score.txt is created in the build/ directory because that's probably where you're executing the binary from.
You can't store score.txt in the /usr/bin directory because, typically, you can't write there without root privileges.
What you want to do is get a path to some directory where you can store your score.txt file. To do that, you can use the QDesktopServices class. That will give you directory information on a per-user basis. Here's an example:
#include <QDesktopServices>
// this would go in main(), probably
QCoreApplication::setApplicationName( "word jumble game" );
// now when you want to read/write the scores file:
QString dataPath = QDesktopService::storageLocation( QDesktopService::DataLocation );
QFile scoreFile( dataPath + "score.txt" );
// on my system, this produces: "/home/adam/.local/share/data/word jumble game/score.txt"
// it will produce something similar for Windows and Mac too
You should set your appication name via QCoreApplication::setApplicationName before getting path information to keep the user data directory nice and organised.
As for getting your application in the games list, you'll need to create a menu entry that follows the freedesktop.org spec. I can't help you more with that, but this is a good starting point. Somebody else might have more info for you.
You need to create a .desktop entry file and install it using xdg-desktop-menu install. Here are two resources for you: freedesktop.org menu spec and adding .desktop files using CMake