New methods in ImageFileFormat for checking file extensions.

extras/Introjucer/Source/Project/jucer_Project.cpp

@@ -454,7 +454,7 @@ Project::Item Project::Item::createGroup (Project& project, const String& name,
 bool Project::Item::isFile() const          { return state.hasType (Tags::file); }
 bool Project::Item::isGroup() const         { return state.hasType (Tags::group) || isMainGroup(); }
 bool Project::Item::isMainGroup() const     { return state.hasType (Tags::projectMainGroup); }
-bool Project::Item::isImageFile() const     { return isFile() && getFile().hasFileExtension ("png;jpg;jpeg;gif;drawable"); }
+bool Project::Item::isImageFile() const     { return isFile() && ImageFileFormat::findImageFormatForFileExtension (getFile()) != nullptr; }
 
 Project::Item Project::Item::findItemWithID (const String& targetId) const
 {

modules/juce_graphics/image_formats/juce_GIFLoader.cpp

@@ -415,7 +415,8 @@ private:
 GIFImageFormat::GIFImageFormat() {}
 GIFImageFormat::~GIFImageFormat() {}
 
-String GIFImageFormat::getFormatName()    { return "GIF"; }
+String GIFImageFormat::getFormatName()                  { return "GIF"; }
+bool GIFImageFormat::usesFileExtension (const File& f)  { return f.hasFileExtension ("gif"); }
 
 bool GIFImageFormat::canUnderstand (InputStream& in)
 {

modules/juce_graphics/image_formats/juce_JPEGLoader.cpp

@@ -210,7 +210,8 @@ void JPEGImageFormat::setQuality (const float newQuality)
     quality = newQuality;
 }
 
-String JPEGImageFormat::getFormatName() { return "JPEG"; }
+String JPEGImageFormat::getFormatName()                   { return "JPEG"; }
+bool JPEGImageFormat::usesFileExtension (const File& f)   { return f.hasFileExtension ("jpeg;jpg"); }
 
 bool JPEGImageFormat::canUnderstand (InputStream& in)
 {

modules/juce_graphics/image_formats/juce_PNGLoader.cpp

@@ -124,7 +124,8 @@ namespace PNGHelpers
 PNGImageFormat::PNGImageFormat()    {}
 PNGImageFormat::~PNGImageFormat()   {}
 
-String PNGImageFormat::getFormatName()  { return "PNG"; }
+String PNGImageFormat::getFormatName()                   { return "PNG"; }
+bool PNGImageFormat::usesFileExtension (const File& f)   { return f.hasFileExtension ("png"); }
 
 bool PNGImageFormat::canUnderstand (InputStream& in)
 {

modules/juce_graphics/images/juce_ImageFileFormat.cpp

@@ -23,35 +23,55 @@
   ==============================================================================
 */
 
-ImageFileFormat* ImageFileFormat::findImageFormatForStream (InputStream& input)
+struct DefaultImageFormats
 {
-    struct DefaultImageFormats
+    static ImageFileFormat** get()
+    {
+        static DefaultImageFormats formats;
+        return formats.formats;
+    }
+
+private:
+    DefaultImageFormats() noexcept
     {
-        PNGImageFormat  png;
-        JPEGImageFormat jpg;
-        GIFImageFormat  gif;
-    };
+        formats[0] = &png;
+        formats[1] = &jpg;
+        formats[2] = &gif;
+        formats[3] = nullptr;
+    }
 
-    static DefaultImageFormats defaultImageFormats;
+    PNGImageFormat  png;
+    JPEGImageFormat jpg;
+    GIFImageFormat  gif;
 
-    ImageFileFormat* formats[] = { &defaultImageFormats.png,
-                                   &defaultImageFormats.jpg,
-                                   &defaultImageFormats.gif };
+    ImageFileFormat* formats[4];
+};
 
+ImageFileFormat* ImageFileFormat::findImageFormatForStream (InputStream& input)
+{
     const int64 streamPos = input.getPosition();
 
-    for (int i = 0; i < numElementsInArray (formats); ++i)
+    for (ImageFileFormat** i = DefaultImageFormats::get(); *i != nullptr; ++i)
     {
-        const bool found = formats[i]->canUnderstand (input);
+        const bool found = (*i)->canUnderstand (input);
         input.setPosition (streamPos);
 
         if (found)
-            return formats[i];
+            return *i;
     }
 
     return nullptr;
 }
 
+ImageFileFormat* ImageFileFormat::findImageFormatForFileExtension (const File& file)
+{
+    for (ImageFileFormat** i = DefaultImageFormats::get(); *i != nullptr; ++i)
+        if ((*i)->usesFileExtension (file))
+            return *i;
+
+    return nullptr;
+}
+
 //==============================================================================
 Image ImageFileFormat::loadFrom (InputStream& input)
 {

modules/juce_graphics/images/juce_ImageFileFormat.h

@@ -57,8 +57,7 @@ public:
     */
     virtual String getFormatName() = 0;
 
-    /** Returns true if the given stream seems to contain data that this format
-        understands.
+    /** Returns true if the given stream seems to contain data that this format understands.
 
         The format class should only read the first few bytes of the stream and sniff
         for header bytes that it understands.
@@ -67,6 +66,9 @@ public:
     */
     virtual bool canUnderstand (InputStream& input) = 0;
 
+    /** Returns true if this format uses the file extension of the given file. */
+    virtual bool usesFileExtension (const File& possibleFile) = 0;
+
     /** Tries to decode and return an image from the given stream.
 
         This will be called for an image format after calling its canUnderStand() method
@@ -92,16 +94,19 @@ public:
                                      OutputStream& destStream) = 0;
 
     //==============================================================================
-    /** Tries the built-in decoders to see if it can find one to read this stream.
-
+    /** Tries the built-in formats to see if it can find one to read this stream.
         There are currently built-in decoders for PNG, JPEG and GIF formats.
-
         The object that is returned should not be deleted by the caller.
-
         @see canUnderstand, decodeImage, loadFrom
     */
     static ImageFileFormat* findImageFormatForStream (InputStream& input);
 
+    /** Looks for a format that can handle the given file extension.
+        There are currently built-in formats for PNG, JPEG and GIF formats.
+        The object that is returned should not be deleted by the caller.
+    */
+    static ImageFileFormat* findImageFormatForFileExtension (const File& file);
+
     //==============================================================================
     /** Tries to load an image from a stream.
 
@@ -130,7 +135,6 @@ public:
     */
     static Image loadFrom (const void* rawData,
                            size_t numBytesOfData);
-
 };
 
 //==============================================================================
@@ -148,6 +152,7 @@ public:
 
     //==============================================================================
     String getFormatName();
+    bool usesFileExtension (const File& possibleFile);
     bool canUnderstand (InputStream& input);
     Image decodeImage (InputStream& input);
     bool writeImageToStream (const Image& sourceImage, OutputStream& destStream);
@@ -177,6 +182,7 @@ public:
 
     //==============================================================================
     String getFormatName();
+    bool usesFileExtension (const File& possibleFile);
     bool canUnderstand (InputStream& input);
     Image decodeImage (InputStream& input);
     bool writeImageToStream (const Image& sourceImage, OutputStream& destStream);
@@ -200,6 +206,7 @@ public:
 
     //==============================================================================
     String getFormatName();
+    bool usesFileExtension (const File& possibleFile);
     bool canUnderstand (InputStream& input);
     Image decodeImage (InputStream& input);
     bool writeImageToStream (const Image& sourceImage, OutputStream& destStream);