Plugin scanning: added a custom scanner callback, and added an option to run the scan on a background thread.

modules/juce_audio_processors/scanning/juce_KnownPluginList.cpp

@@ -68,7 +68,7 @@ bool KnownPluginList::addType (const PluginDescription& type)
         }
     }
 
-    types.add (new PluginDescription (type));
+    types.insert (0, new PluginDescription (type));
     sendChangeMessage();
     return true;
 }
@@ -116,6 +116,11 @@ bool KnownPluginList::isListingUpToDate (const String& fileOrIdentifier) const
     return true;
 }
 
+void KnownPluginList::setCustomScanner (CustomScanner* newScanner)
+{
+    scanner = newScanner;
+}
+
 bool KnownPluginList::scanAndAddFile (const String& fileOrIdentifier,
                                       const bool dontRescanIfAlreadyInList,
                                       OwnedArray <PluginDescription>& typesFound,
@@ -147,7 +152,11 @@ bool KnownPluginList::scanAndAddFile (const String& fileOrIdentifier,
         return false;
 
     OwnedArray <PluginDescription> found;
-    format.findAllTypesForFile (found, fileOrIdentifier);
+
+    if (scanner != nullptr)
+        scanner->findPluginTypesFor (format, found, fileOrIdentifier);
+    else
+        format.findAllTypesForFile (found, fileOrIdentifier);
 
     for (int i = 0; i < found.size(); ++i)
     {
@@ -167,29 +176,39 @@ void KnownPluginList::scanAndAddDragAndDroppedFiles (AudioPluginFormatManager& f
 {
     for (int i = 0; i < files.size(); ++i)
     {
+        const String filenameOrID (files[i]);
+        bool found = false;
+
         for (int j = 0; j < formatManager.getNumFormats(); ++j)
         {
             AudioPluginFormat* const format = formatManager.getFormat (j);
 
-            if (scanAndAddFile (files[i], true, typesFound, *format))
-                return;
+            if (format->fileMightContainThisPluginType (filenameOrID)
+                 && scanAndAddFile (filenameOrID, true, typesFound, *format))
+            {
+                found = true;
+                break;
+            }
         }
 
-        const File f (files[i]);
-
-        if (f.isDirectory())
+        if (! found)
         {
-            StringArray s;
+            const File f (filenameOrID);
 
+            if (f.isDirectory())
             {
-                Array<File> subFiles;
-                f.findChildFiles (subFiles, File::findFilesAndDirectories, false);
+                StringArray s;
 
-                for (int j = 0; j < subFiles.size(); ++j)
-                    s.add (subFiles.getReference(j).getFullPathName());
+                {
+                    Array<File> subFiles;
+                    f.findChildFiles (subFiles, File::findFilesAndDirectories, false);
+
+                    for (int j = 0; j < subFiles.size(); ++j)
+                        s.add (subFiles.getReference(j).getFullPathName());
+                }
+
+                scanAndAddDragAndDroppedFiles (formatManager, s, typesFound);
             }
-
-            scanAndAddDragAndDroppedFiles (formatManager, s, typesFound);
         }
     }
 }
@@ -485,3 +504,7 @@ int KnownPluginList::getIndexChosenByMenu (const int menuResultCode) const
     const int i = menuResultCode - menuIdBase;
     return isPositiveAndBelow (i, types.size()) ? i : -1;
 }
+
+//==============================================================================
+KnownPluginList::CustomScanner::CustomScanner() {}
+KnownPluginList::CustomScanner::~CustomScanner() {}

modules/juce_audio_processors/scanning/juce_KnownPluginList.h

@@ -179,10 +179,25 @@ public:
     /** Creates a PluginTree object containing all the known plugins. */
     PluginTree* createTree (const SortMethod sortMethod) const;
 
+    //==============================================================================
+    class CustomScanner
+    {
+    public:
+        CustomScanner();
+        virtual ~CustomScanner();
+
+        virtual void findPluginTypesFor (AudioPluginFormat& format,
+                                         OwnedArray <PluginDescription>& result,
+                                         const String& fileOrIdentifier) = 0;
+    };
+
+    void setCustomScanner (CustomScanner* scanner);
+
 private:
     //==============================================================================
     OwnedArray <PluginDescription> types;
     StringArray blacklist;
+    ScopedPointer<CustomScanner> scanner;
 
     JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (KnownPluginList)
 };

modules/juce_audio_processors/scanning/juce_PluginListComponent.cpp

@@ -31,7 +31,8 @@ PluginListComponent::PluginListComponent (AudioPluginFormatManager& manager,
       list (listToEdit),
       deadMansPedalFile (deadMansPedal),
       optionsButton ("Options..."),
-      propertiesToUse (properties)
+      propertiesToUse (properties),
+      scanOnBackgroundThread (false)
 {
     listBox.setModel (this);
     addAndMakeVisible (&listBox);
@@ -59,6 +60,11 @@ void PluginListComponent::setOptionsButtonText (const String& newText)
     resized();
 }
 
+void PluginListComponent::setScansOnMessageThread (bool useMessageThread) noexcept
+{
+    scanOnBackgroundThread = ! useMessageThread;
+}
+
 void PluginListComponent::resized()
 {
     listBox.setBounds (0, 0, getWidth(), getHeight() - 30);
@@ -237,42 +243,79 @@ void PluginListComponent::filesDropped (const StringArray& files, int, int)
 }
 
 //==============================================================================
-class PluginListComponent::Scanner    : private Timer
+class PluginListComponent::Scanner    : private Timer,
+                                        private Thread
 {
 public:
-    Scanner (PluginListComponent& plc, AudioPluginFormat& format, const FileSearchPath& path)
-        : owner (plc),
+    Scanner (PluginListComponent& plc,
+             AudioPluginFormat& format,
+             const FileSearchPath& path,
+             bool useThread)
+        : Thread ("plugin_scan"),
+          owner (plc),
           aw (TRANS("Scanning for plug-ins..."),
               TRANS("Searching for all possible plug-in files..."), AlertWindow::NoIcon),
-          progress (0.0),
+          progress (0.0), finished (false),
           scanner (owner.list, format, path, true, owner.deadMansPedalFile)
     {
         aw.addButton (TRANS("Cancel"), 0, KeyPress (KeyPress::escapeKey));
         aw.addProgressBarComponent (progress);
         aw.enterModalState();
 
+        if (useThread)
+            startThread();
+
         startTimer (20);
     }
 
+    ~Scanner()
+    {
+        stopThread (10000);
+    }
+
 private:
     void timerCallback()
     {
-        aw.setMessage (TRANS("Testing:\n\n") + scanner.getNextPluginFileThatWillBeScanned());
+        if (! isThreadRunning())
+        {
+            if (doNextScan())
+                startTimer (20);
+        }
 
-        if (scanner.scanNextFile (true) && aw.isCurrentlyModal())
+        if (! aw.isCurrentlyModal())
+            finished = true;
+
+        if (finished)
+            owner.scanFinished (scanner.getFailedFiles());
+        else
+            aw.setMessage (progressMessage);
+    }
+
+    void run()
+    {
+        while (doNextScan() && ! threadShouldExit())
+        {}
+    }
+
+    bool doNextScan()
+    {
+        progressMessage = TRANS("Testing:\n\n") + scanner.getNextPluginFileThatWillBeScanned();
+
+        if (scanner.scanNextFile (true))
         {
             progress = scanner.getProgress();
-            startTimer (20);
-        }
-        else
-        {
-            owner.scanFinished (scanner.getFailedFiles());
+            return true;
         }
+
+        finished = true;
+        return false;
     }
 
     PluginListComponent& owner;
     AlertWindow aw;
+    String progressMessage;
     double progress;
+    bool finished;
     PluginDirectoryScanner scanner;
 };
 
@@ -312,7 +355,7 @@ void PluginListComponent::scanFor (AudioPluginFormat* format)
             propertiesToUse->saveIfNeeded();
         }
 
-        currentScanner = new Scanner (*this, *format, path);
+        currentScanner = new Scanner (*this, *format, path, scanOnBackgroundThread);
     }
 }
 

modules/juce_audio_processors/scanning/juce_PluginListComponent.h

@@ -61,6 +61,9 @@ public:
     /** Changes the text in the panel's button. */
     void setOptionsButtonText (const String& newText);
 
+    /** Chooses whether to use the message thread or a background thread for scanning. */
+    void setScansOnMessageThread (bool useMessageThread) noexcept;
+
     //==============================================================================
     /** @internal */
     void resized();
@@ -83,6 +86,7 @@ private:
     ListBox listBox;
     TextButton optionsButton;
     PropertiesFile* propertiesToUse;
+    bool scanOnBackgroundThread;
 
     class Scanner;
     friend class Scanner;