welcome screen: populate example combobox

When an example is selected, help and the project are opened
in a split view. We try to read the xml file provided for
QtDemo to extract details about the examples provided. Will
try all available Qts, starting with the default version. Will
fail gracefully (provide a message and disable controls) if
examples or demos cannot be found. Will work if help is not
found, but show an error.

src/plugins/qt4projectmanager/qtversionmanager.cpp

@@ -35,7 +35,10 @@
 #include <projectexplorer/debugginghelper.h>
 #include <projectexplorer/projectexplorer.h>
 #include <projectexplorer/cesdkhandler.h>
+#include <coreplugin/coreconstants.h>
 #include <coreplugin/icore.h>
+#include <coreplugin/modemanager.h>
+#include <coreplugin/welcomemode.h>
 #include <extensionsystem/pluginmanager.h>
 #include <help/helpplugin.h>
 #include <utils/qtcassert.h>
@@ -98,7 +101,15 @@ QtVersionManager::QtVersionManager()
     updateSystemVersion();
 
     writeVersionsIntoSettings();
+
+    if (Core::Internal::WelcomeMode *welcomeMode = qobject_cast<Core::Internal::WelcomeMode*>
+        (Core::ICore::instance()->modeManager()->mode(Core::Constants::MODE_WELCOME))) {
+        connect(this, SIGNAL(updatedExamples(QString,QString,QString)),
+                welcomeMode, SIGNAL(updatedExamples(QString,QString, QString)));
+    }
+    else
     updateDocumentation();
+    updateExamples();
 }
 
 QtVersionManager::~QtVersionManager()
@@ -129,13 +140,38 @@ void QtVersionManager::updateDocumentation()
     QStringList fileEndings = QStringList() << "/qch/qt.qch" << "/qch/qmake.qch" << "/qch/designer.qch";
     QStringList files;
     foreach (QtVersion *version, m_versions) {
-        QString docPath = version->versionInfo().value("QT_INSTALL_DOCS");
+        QString docPath = version->documentationPath();
         foreach (const QString &fileEnding, fileEndings)
             files << docPath+fileEnding;
     }
     helpManager->registerDocumentation(files);
 }
 
+void QtVersionManager::updateExamples()
+{
+    QList<QtVersion *> versions;
+    versions.append(currentQtVersion());
+    versions.append(m_versions);
+
+    QString examplesPath;
+    QString docPath;
+    QString demosPath;
+    QtVersion *version = 0;
+    // try to find a version which has both, examples and docs, starting with default Qt
+    foreach (version, versions) {
+        if (version->hasExamples())
+            examplesPath = version->examplesPath();
+        if (version->hasDemos())
+            demosPath = version->demosPath();
+        if (version->hasDocumentation())
+            docPath = version->documentationPath();
+        if (!examplesPath.isEmpty() && !demosPath.isEmpty() && !docPath.isEmpty()) {
+            emit updatedExamples(examplesPath, demosPath, docPath);
+            return;
+        }
+    }
+}
+
 int QtVersionManager::getUniqueId()
 {
     return m_idcount++;
@@ -302,8 +338,10 @@ void QtVersionManager::setNewQtVersions(QList<QtVersion *> newVersions, int newD
     }
 
     emit qtVersionsChanged();
-    if (emitDefaultChanged)
+    if (emitDefaultChanged) {
         emit defaultQtVersionChanged();
+        updateExamples();
+    }
 
     writeVersionsIntoSettings();
 }
@@ -321,6 +359,9 @@ QtVersion::QtVersion(const QString &name, const QString &path, int id, bool isSy
     m_notInstalled(false),
     m_defaultConfigIsDebug(true),
     m_defaultConfigIsDebugAndRelease(true),
+    m_hasExamples(false),
+    m_hasDemos(false),
+    m_hasDocumentation(false),
     m_toolChain(0)
 {
     if (id == -1)
@@ -600,6 +641,8 @@ void QtVersion::updateVersionInfo() const
     // extract data from qmake executable
     m_versionInfo.clear();
     m_notInstalled = false;
+    m_hasExamples = false;
+    m_hasDocumentation = false;
     QFileInfo qmake(qmakeCommand());
     if (qmake.exists()) {
         static const char * const variables[] = {
@@ -645,6 +688,21 @@ void QtVersion::updateVersionInfo() const
             if (!fi.exists())
                 m_notInstalled = true;
         }
+        if (m_versionInfo.contains("QT_INSTALL_DOCS")){
+            QFileInfo fi(m_versionInfo.value("QT_INSTALL_DOCS"));
+            if (fi.exists())
+                m_hasDocumentation = true;
+        }
+        if (m_versionInfo.contains("QT_INSTALL_EXAMPLES")){
+            QFileInfo fi(m_versionInfo.value("QT_INSTALL_EXAMPLES"));
+            if (fi.exists())
+                m_hasExamples = true;
+        }
+        if (m_versionInfo.contains("QT_INSTALL_DEMOS")){
+            QFileInfo fi(m_versionInfo.value("QT_INSTALL_DEMOS"));
+            if (fi.exists())
+                m_hasDemos = true;
+        }
 
         // Parse qconfigpri
         QString baseDir = m_versionInfo.contains("QT_INSTALL_DATA") ?
@@ -1010,6 +1068,41 @@ QString QtVersion::debuggingHelperLibrary() const
     return DebuggingHelperLibrary::debuggingHelperLibrary(qtInstallData, path());
 }
 
+bool QtVersion::hasDocumentation() const
+{
+    updateVersionInfo();
+    return m_hasDocumentation;
+}
+
+QString QtVersion::documentationPath() const
+{
+    updateVersionInfo();
+    return m_versionInfo["QT_INSTALL_DOCS"];
+}
+
+bool QtVersion::hasDemos() const
+{
+    updateVersionInfo();
+    return m_hasDemos;
+}
+
+QString QtVersion::demosPath() const
+{
+    updateVersionInfo();
+    return m_versionInfo["QT_INSTALL_DEMOS"];
+}
+
+bool QtVersion::hasExamples() const
+{
+    updateVersionInfo();
+    return m_hasExamples;
+}
+
+QString QtVersion::examplesPath() const
+{
+    updateVersionInfo();
+    return m_versionInfo["QT_INSTALL_EXAMPLES"];
+}
 
 bool QtVersion::isMSVC64Bit() const
 {