Look and Feel crash when unload and reload

General JUCE discussion
1

Hello.

I'm having a problem with my plugin crashing. I can create and unload as many instances as I want, however, when I remove the last instance and then create another one, it crashes the host.

I believe the look and feel is causing the problem. It happens in both AU and VST versions. I'm on OSX Yosemite.

I'm inheriting deletedAtShutdown, and using a singleton http://www.juce.com/forum/topic/setdefaultlookandfeel

I've tried decalring singleton false for doNotRecreateAfterDeletion, but that will not reload the L&F if I reload the plugin after unloading it, and defaults to the stock V3 Look and feel.

 

Have I missed something silly? Should I be checking if the singleton exists before calling getInstance()?

EDIT: Oh, and I'm pretty sure this didn't happen until I updated the modules to the latest version. I was only a couple of points behind until the update.

Cheers..

Here's my crash log and implementation....

 

eg. .h

class MyLookAndFeel    : public LookAndFeel_V3,
                            public DeletedAtShutdown

{

public:
    MyLookAndFeel();
    ~MyLookAndFeel();
    juce_DeclareSingleton (MyLookAndFeel, true);

    void drawButtonBackground (Graphics&, Button&, const Colour& backgroundColour,
                               bool isMouseOverButton, bool isButtonDown) override;

 

eg.cpp

MyLookAndFeel::MyLookAndFeel()
{
}

MyLookAndFeel::~MyLookAndFeel()
{
}

juce_ImplementSingleton (MyLookAndFeel)

 

and in the editor...

LookAndFeel::setDefaultLookAndFeel(MyLookAndFeel::getInstance());

Here's the crash report from Apple.....

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   com.MyPluginID.MyPlugin    0x0000000128357d38 juce::ComboBox::lookAndFeelChanged() + 68
1   com.MyPluginID.MyPlugin    0x000000012832193d juce::Component::internalHierarchyChanged() + 71
2   com.MyPluginID.MyPlugin    0x0000000128321999 juce::Component::internalHierarchyChanged() + 163
3   com.MyPluginID.MyPlugin    0x00000001283231fd juce::Component::addChildComponent(juce::Component&, int) + 211
4   com.MyPluginID.MyPlugin    0x0000000128292fb4 MyPluginAudioProcessorEditor::MyPluginAudioProcessorEditor(MyPluginAudioProcessor*) + 1330
5   com.MyPluginID.MyPlugin    0x0000000128292332 MyPluginAudioProcessor::createEditor() + 34
6   com.MyPluginID.MyPlugin    0x00000001282a8ecd juce::AudioProcessor::createEditorIfNeeded() + 63
7   com.MyPluginID.MyPlugin    0x00000001282a3ff3 JuceAU::JuceUICreationClass::uiViewForAudioUnit(objc_object*,
2

**Added to original post**

3

It’s good practice to call setDefaultLookAndFeel in your processor. This way it is already set before your editor is constructed. 1

I once had issues even when it was called first in the editors constructor. Some parts where just not taken from my own LookAndFeel.

4

Hard to tell from the stack trace, but probably some sort of callback happening during a constructor that's causing a pure virtual call?

5

Cheers guys. Done a bit more debugging, and it's inheriting from DeletedAtShutdown that's causing the problem. If I remove this and call LookAndFeel::setDefaultLookAndFeel(MyLookAndFeel::getInstance()); , will the L&F class still deal with any clearing up that's needed?