MacOSX: editing hierarchical .plist files with QSettings

[Max]

I would like to mark a file extension as "Safe to open from the Internet".
To do so I need to create a preferences file ~/Library/Preferences/com.apple.DownloadAssessment.plist and add the extension to that.

If the file already exists, I need to preserve its existing settings, so simply overwriting the file is not an option.
I tried to use QSettings to edit it like this:

void MainWindow::_markExtensionSafe(const QString &ext)
{
    qDebug() << "Marking extension" << ext << "as safe to open instead of download";
 
    QString filename = QDesktopServices::storageLocation(QDesktopServices::HomeLocation)+"/Library/Preferences/com.apple.DownloadAssessment.plist";
    QString key      = "LSRiskCategorySafe/LSRiskCategoryExtensions";
 
    QSettings plist(filename, QSettings::NativeFormat);
    QVariant currentSetting = plist.value(key);
    QStringList exts = currentSetting.toStringList();
 
    if ( !exts.contains(ext) ) /* add extension if it doesn't exists already */
    {
        exts << ext;
        plist.setValue(key, exts);
    }
}

void MainWindow::_markExtensionSafe(const QString &ext)
{
    qDebug() << "Marking extension" << ext << "as safe to open instead of download";

    QString filename = QDesktopServices::storageLocation(QDesktopServices::HomeLocation)+"/Library/Preferences/com.apple.DownloadAssessment.plist";
    QString key      = "LSRiskCategorySafe/LSRiskCategoryExtensions";

    QSettings plist(filename, QSettings::NativeFormat);
    QVariant currentSetting = plist.value(key);
    QStringList exts = currentSetting.toStringList();

    if ( !exts.contains(ext) ) /* add extension if it doesn't exists already */
    {
        exts << ext;
        plist.setValue(key, exts);
    }
}

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But it generates:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>LSRiskCategorySafe.LSRiskCategoryExtensions</key>
	<array>
		<string>myextension</string>
	</array>
</dict>
</plist>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>LSRiskCategorySafe.LSRiskCategoryExtensions</key>
	<array>
		<string>myextension</string>
	</array>
</dict>
</plist>

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While the format supposedly has to look like this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN"
"http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>LSRiskCategorySafe</key>
	<dict>
		<key>LSRiskCategoryExtensions</key>
		<array>
			<string>myextension</string>
		</array>
	</dict>
</dict>
</plist>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN"
"http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>LSRiskCategorySafe</key>
	<dict>
		<key>LSRiskCategoryExtensions</key>
		<array>
			<string>myextension</string>
		</array>
	</dict>
</dict>
</plist>

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Is there a way to tell QSettings to create proper subkeys?
Or am I better off editing the file using the XML functions instead?

---

Added after 1 20 minutes:

Also tried this:

void MainWindow::_markExtensionSafe(const QString &ext)
{
    qDebug() << "Marking extension" << ext << "as safe to open instead of download";
 
    QString filename = QDesktopServices::storageLocation(QDesktopServices::HomeLocation)+"/Library/Preferences/com.apple.DownloadAssessment.plist";
 
    QString key      = "LSRiskCategorySafe";
    QString subkey   = "LSRiskCategoryExtensions";
 
    QSettings plist(filename, QSettings::NativeFormat);
    QVariantMap map  = plist.value(key).toMap();
    QStringList exts = map.value(subkey).toStringList();
 
    if ( !exts.contains(ext) ) /* add extension if it doesn't exists already */
    {
        exts << ext;
        map[subkey] = exts;
        plist.setValue(key, map);
    }
}

void MainWindow::_markExtensionSafe(const QString &ext)
{
    qDebug() << "Marking extension" << ext << "as safe to open instead of download";

    QString filename = QDesktopServices::storageLocation(QDesktopServices::HomeLocation)+"/Library/Preferences/com.apple.DownloadAssessment.plist";

    QString key      = "LSRiskCategorySafe";
    QString subkey   = "LSRiskCategoryExtensions";

    QSettings plist(filename, QSettings::NativeFormat);
    QVariantMap map  = plist.value(key).toMap();
    QStringList exts = map.value(subkey).toStringList();

    if ( !exts.contains(ext) ) /* add extension if it doesn't exists already */
    {
        exts << ext;
        map[subkey] = exts;
        plist.setValue(key, map);
    }
}

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But then it generates:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>LSRiskCategorySafe</key>
	<dict>
		<key>LSRiskCategoryExtensions</key>
		<array>
			<array>
				<string>myextension</string>
			</array>
		</array>
	</dict>
</dict>
</plist>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>LSRiskCategorySafe</key>
	<dict>
		<key>LSRiskCategoryExtensions</key>
		<array>
			<array>
				<string>myextension</string>
			</array>
		</array>
	</dict>
</dict>
</plist>

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Don't understand why it generates <array> two times.

[yurenjimi]

Don't understand why it generates <array> two times.


Yes, i has the same problem with Qt5.2 and OS X 10.9..
Has you solved the problem ?