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29 \page qdeclarativedebugging.html
34 \c console.log can be used to print debugging information to the console. For example:
38 width: 200; height: 200
41 onClicked: console.log("clicked")
46 \section1 Debugging Transitions
48 When a transition doesn't look quite right, it can be helpful to view it in slow
49 motion to see what is happening more clearly. This functionality is supported
50 in the \l {QML Viewer} tool: to enable this,
51 click on the "Debugging" menu, then "Slow Down Animations".
54 \section1 Debugging module imports
56 The \c QML_IMPORT_TRACE environment variable can be set to enable debug output
57 from QML's import loading mechanisms.
59 For example, for a simple QML file like this:
64 Rectangle { width: 100; height: 100 }
67 If you set \c {QML_IMPORT_TRACE=1} before running the \l {QML Viewer}
68 (or your QML C++ application), you will see output similar to this:
71 QDeclarativeImportDatabase::addImportPath "/qt-sdk/imports"
72 QDeclarativeImportDatabase::addImportPath "/qt-sdk/bin/QMLViewer.app/Contents/MacOS"
73 QDeclarativeImportDatabase::addToImport 0x106237370 "." -1.-1 File as ""
74 QDeclarativeImportDatabase::addToImport 0x106237370 "Qt" 4.7 Library as ""
75 QDeclarativeImportDatabase::resolveType "Rectangle" = "QDeclarativeRectangle"
79 \section1 Debugging with Qt Creator
81 \l{http://qt.nokia.com/products/developer-tools}{Qt Creator} provides built-in
82 support for QML debugging. QML projects and standalone C++ applications that
83 utilize QML can be debugged on desktops as well as on remote devices.
84 For more information, see the Qt Creator Manual.