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