Store custom Component into Vector

General JUCE discussion
1

Hello, I'm trying to store a custom class that I made (called Circle), which inherits from Component, into a vector so I can draw a collection of circles all over the screen and erase them. I want to add the with push_back() and erase with pop_back. I'm only overriding the paint() method. I'm getting a compile every when I try to use push_back though and I can't seem to figure out how to do it.

Here's the error:

Error    2    error C2248: 'juce::Component::Component' : cannot access private member declared in class 'juce::Component' (..\..\Source\MainComponent.cpp) 

 

Here's the class:

 

class Circle    : public Component 
{ 
public: 
Circle(const float x, const float y, const float radius, const Colour colour); 
void paint (Graphics&); 

private: 
    float m_x; 
    float m_y; 
    float m_radius; 
    Colour m_colour; 
    float m_diameter; 
}; 

Circle::Circle(const float x, const float y, const float radius, const Colour colour) 
    :m_x{ x }, m_y{ y }, m_radius{ radius }, m_colour{ colour } 
{ 
    m_diameter = m_radius * 2;
} 

void Circle::paint(Graphics& g) 
{
    g.setColour(m_colour); 
    g.fillEllipse(m_x, m_y, m_diameter, m_diameter); 
}

 

And I'm just trying to use it something like this:

vector<Circle> circles;

circles.push_back(Circle{ x, y, 10.0f, red });

 

I'm sure there's a much better way of doing this, but I'm new to JUCE and this is similar to the way I did it in Cinder. If anyone knows how to fix this, or even a better way of doing this I would be really grateful. Idk why I can't get this to work. I don't know if I should even be inheriting from Component.

 

 

2

Actually, I just didn't inheret from anything and I got it working. I guess that'll work for what I'm wanting to do. :)

3

I'm still curious if you can create and store components in an array though. I'd like to create an array of circles then somehow move those circles around by clicking + dragging them. 

4

Well.... just try this to call the constructor instead of loading directly the private members, it should work better :-)

circles.push_back(Circle ( x, y, 10.0f, red ) );

But anyway you should consider using Juce's Array or OwnedArray instead of stdlib members. Take time having a look at the complete Juce object model, you'll find a lot of useful things that will simplify your life ;-)

 

/Phil

5

Thanks for replying man. I'll have to check out JUCE's arrays and other data structures. This is just practice anyways. I'm trying to learn as much about JUCE as I can and I thought this would be a good exercise. 

6

What do you know, Getting Started With JUCE has 2 sections on storing components in the JUCE Array and OwnedArray classes. Man, I feel dumb for not noticing that. Now I should be able to figure that out. :) That's in chapter 3 if anyone else needs this.

7

Component is NOT copyable (and AFAIK not movable)?

8

No - how could it be copyable!? If you copy it, what would happen to its child components or parent component? What about all the listeners that are attached? etc etc!

9

Hey Jules, it was not a question. It was just a suggestion to the OP why using a vector of Components is not a good idea. Of course it can not be copied :wink:

1 Like
10

Sure :)

I was just confirming why that's the case, for anyone who might have been reading and not seeing why that is.

1 Like
11

i had a feeling that's what it was. Thanks for replying everyone. I'm still figuring out how components work. I love how helpful this forum is. Sorry for all the noob questions. I try to only ask if I can't find the answer.