Print float value

Audio Plugins
#1

Hello!

I am new to juce and I have a question.
I am building an audio plugin with Juce and I computed a float value in the process block.
What I want now is to print it on the GUI, instead of the ‘Hello World’ message.

I tried to use the variable in the process editor:
g.drawFittedText (String(valueLevelLeft), getLocalBounds(), Justification::centred, 1);

But it doesn’t see my variable ‘valueLevelLeft’, which I defined in the PluginProcessor header and used in the PluginProcessor.cpp. (error message: Use of undeclared identifier ‘valueLevelLeft’)

How can I pass this variable from the processor to the editor?

#2

You can do :

But couple of additional things :

  • The valueLevelLeft should be an atomic variable to avoid wrong behaviors which might happen due to compiler optimizations and the multiple threads involved. (Use std::atomic<float> instead of just float.)
  • The GUI will not repaint itself automatically, you will need to inherit your plugin editor from Timer too and implement the timerCallback method, which should call repaint().
#3

Thank you so much!

I have one more question (sorry if it sounds stupid, I am trying to learn).
I inherited Timer and implemented timerCallback in the Editor.h:

class TrialAudioProcessorEditor : public AudioProcessorEditor, public Timer
{
public :

TrialAudioProcessorEditor (TrialAudioProcessor&);
~TrialAudioProcessorEditor();

void timerCallback() override ;

void paint (Graphics&) override ;

void resized() override ;
private:
… }

Now in the Editor.cpp I did this:

TrialAudioProcessorEditor::TrialAudioProcessorEditor (TrialAudioProcessor& p)
: AudioProcessorEditor (&p), processor §
{
startTimer(200);
}

TrialAudioProcessorEditor::~TrialAudioProcessorEditor()
{
stopTimer();
}

void timerCallback() override {
repaint();
}

void TrialAudioProcessorEditor::paint (Graphics& g) override
{. ….
g.drawFittedText (String(processor.valueLevelLeft), getLocalBounds(), Justification::centred, 1);
}

void TrialAudioProcessorEditor::resized()
{
}

I get the error: Expected function body after function declarator for ‘‘void timerCallback() override’’.

Could you tell me what am I doing wrong?

Thank you and sorry for spamming :slight_smile:

#4

That is, because in the implementation you need to add it to the namespace, and furthermore the override keyword is only allowed in a declaration, not in the cpp file.

Last but not least, please add three backticks before and after your code, otherwise the forum might remove symbols, like e.g. angle brackets

    ```
    int main()
    {
        return 0;
    }
    ```

Thanks
P.S., using the pen symbol you can edit your posts, no need to post it again