qml runtime tool: support alternate conf; add resizeToItem conf

The qmlscene --resize-to-root feature has always been missing from
the qml runtime tool; however it was already possible to add it by
writing a custom configuration file.  Now we support loading different
configurations from resources as well as from the filesystem, and
the first new configuration being added here is resizeToItem.qml
which provides behavior equivalent to qmlscene --resize-to-root.

When the argument given to --config ends with .qml, by convention
it's to be loaded from the filesystem; whereas configurations from
resources are specified without the .qml extension (to make the
command line shorter).

[ChangeLog][QtQml][qml] The QML Runtime tool now has default behavior
matching qmlscene when the root QML object is an Item: it will be
wrapped in a Window which will resize the Item when the Window is
resized.  But you can alternatively use the --config resizeToItem
option, resulting in the same behavior as qmlscene --resizeToRoot:
resizing the root Item programmatically causes the wrapping Window to
be resized.  Behavior can still be customized in other ways using the
--config option with an external QML configuration file.

Task-number: QTBUG-53557
Change-Id: Icdcbbd12258105c33b64634049d735e022dfbd06
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 37 insertions, 13 deletions

diff --git a/tools/qml/main.cpp b/tools/qml/main.cpp
index 1d520b8fde..1e367d91bf 100644
--- a/tools/qml/main.cpp
+++ b/tools/qml/main.cpp
@@ -95,12 +95,13 @@ static QQmlApplicationEngine *qae = nullptr;
 static int exitTimerId = -1;
 #endif
 static const QString iconResourcePath(QStringLiteral(":/qt-project.org/QmlRuntime/resources/qml-64.png"));
+static const QString confResourcePath(QStringLiteral(":/qt-project.org/QmlRuntime/conf/"));
 static bool verboseMode = false;
 static bool quietMode = false;
 
 static void loadConf(const QString &override, bool quiet) // Terminates app on failure
 {
-    const QString defaultFileName = QLatin1String("configuration.qml");
+    const QString defaultFileName = QLatin1String("default.qml");
     QUrl settingsUrl;
     bool builtIn = false; //just for keeping track of the warning
     if (override.isEmpty()) {
@@ -110,29 +111,38 @@ static void loadConf(const QString &override, bool quiet) // Terminates app on f
             settingsUrl = QUrl::fromLocalFile(fi.absoluteFilePath());
         } else {
             // ### If different built-in configs are needed per-platform, just apply QFileSelector to the qrc conf.qml path
-            settingsUrl = QUrl(QLatin1String("qrc:///qt-project.org/QmlRuntime/conf/") + defaultFileName);
+            fi.setFile(confResourcePath + defaultFileName);
+            settingsUrl = QUrl::fromLocalFile(fi.absoluteFilePath());
             builtIn = true;
         }
     } else {
         QFileInfo fi;
-        fi.setFile(override);
-        if (!fi.exists()) {
-            printf("qml: Couldn't find required configuration file: %s\n",
-                    qPrintable(QDir::toNativeSeparators(fi.absoluteFilePath())));
-            exit(1);
+        fi.setFile(confResourcePath + override + QLatin1String(".qml"));
+        if (fi.exists()) {
+            settingsUrl = QUrl::fromLocalFile(fi.absoluteFilePath());
+            builtIn = true;
+        } else {
+            fi.setFile(override);
+            if (!fi.exists()) {
+                printf("qml: Couldn't find required configuration file: %s\n",
+                       qPrintable(QDir::toNativeSeparators(fi.absoluteFilePath())));
+                exit(1);
+            }
+            settingsUrl = QUrl::fromLocalFile(fi.absoluteFilePath());
         }
-        settingsUrl = QUrl::fromLocalFile(fi.absoluteFilePath());
     }
 
     if (!quiet) {
         printf("qml: %s\n", QLibraryInfo::build());
-        if (builtIn)
-            printf("qml: Using built-in configuration.\n");
-        else
-            printf("qml: Using configuration file: %s\n",
+        if (builtIn) {
+            printf("qml: Using built-in configuration: %s\n",
+                   qPrintable(override.isEmpty() ? defaultFileName : override));
+        } else {
+            printf("qml: Using configuration: %s\n",
                     qPrintable(settingsUrl.isLocalFile()
                     ? QDir::toNativeSeparators(settingsUrl.toLocalFile())
                     : settingsUrl.toString()));
+        }
     }
 
     // TODO: When we have better engine control, ban QtQuick* imports on this engine
@@ -153,6 +163,15 @@ void noFilesGiven()
     exit(1);
 }
 
+static void listConfFiles()
+{
+    QDir confResourceDir(confResourcePath);
+    printf("%s\n", qPrintable(QCoreApplication::translate("main", "Built-in configurations:")));
+    for (const QFileInfo &fi : confResourceDir.entryInfoList(QDir::Files))
+        printf("  %s\n", qPrintable(fi.baseName()));
+    exit(0);
+}
+
 #ifdef QT_GUI_LIB
 
 // Loads qml after receiving a QFileOpenEvent
@@ -435,8 +454,11 @@ int main(int argc, char *argv[])
         QCoreApplication::translate("main", "Load the given file as a QML file."), QStringLiteral("file"));
     parser.addOption(qmlFileOption);
     QCommandLineOption configOption(QStringList() << QStringLiteral("c") << QStringLiteral("config"),
-        QCoreApplication::translate("main", "Load the given file as the configuration file."), QStringLiteral("file"));
+        QCoreApplication::translate("main", "Load the given built-in configuration or configuration file."), QStringLiteral("file"));
     parser.addOption(configOption);
+    QCommandLineOption listConfOption(QStringList() << QStringLiteral("list-conf"),
+                                      QCoreApplication::translate("main", "List the built-in configurations."));
+    parser.addOption(listConfOption);
     QCommandLineOption translationOption(QStringLiteral("translation"),
         QCoreApplication::translate("main", "Load the given file as the translations file."), QStringLiteral("file"));
     parser.addOption(translationOption);
@@ -486,6 +508,8 @@ int main(int argc, char *argv[])
         parser.showVersion();
     if (parser.isSet(helpOption))
         parser.showHelp();
+    if (parser.isSet(listConfOption))
+        listConfFiles();
     if (applicationType == QmlApplicationTypeUnknown) {
 #ifdef QT_WIDGETS_LIB
         qWarning() << QCoreApplication::translate("main", "--apptype must be followed by one of the following: core gui widget\n");