Question

I’m making an app which for now, parses an url and takes some info from it. I want to use this values to create objects, put them into an arraylist, and show them on screen with a ListView layout.

Problem comes when i want to assign drawables values from the object. I want, depending on its values, assign a drawable or another. Here is the code:

Retransmision retransmision = new Retransmision();
retransmision.setIdioma(idioma);
retransmision.setTipo(tipo);
retransmision.setCalidad(calidad);
retransmision.setLink(link);
retransmision.setImagenLogo(tipo);
retransmision.setImagenCalidad(calidad);
retransmisionesDescargadas.add(retransmision);

I just create the object and assign some values with its methods. And heres the method wich is throwing nullPointerException:

public void setImagenCalidad(int calidad) {
if (calidad == 0) {
imagenCalidad = context.getResources().getDrawable(R.drawable.desconocida);
} else if(calidad <= 250) {
imagenCalidad = context.getResources().getDrawable(R.drawable.baja);
} else if(calidad <= 500) {
imagenCalidad = context.getResources().getDrawable(R.drawable.media);
} else if(calidad <= 750) {
imagenCalidad = context.getResources().getDrawable(R.drawable.alta);
} else if(calidad <= 1000) {
imagenCalidad = context.getResources().getDrawable(R.drawable.muy_alta);
} else {
imagenCalidad = context.getResources().getDrawable(R.drawable.excelente);
}
}

Weird since i use a similar code for method setImagenLogo that seems to work well. And only difference is one gets a String parameter. And the other an int.

Ps: If it might help, this is the constructor of the retransmision object and its variables:

Context context;
    private String idioma;
    private String tipo;
    private int calidad;
    private String link;
    private Drawable imagenLogo;
    private Drawable imagenIdioma;
    private Drawable imagenCalidad;
    
    public Retransmision() {
        idioma = "";
        tipo = "";
        calidad = 0;
        link = "";
        imagenLogo = null;
        imagenIdioma = null;
        imagenCalidad = null;
    }

Answer 1

The only thing that could be null there is the context… and I see you didn’t initialize it in your constructor. Maybe this is what you want:

public Retransmision(Context ctx) {
    idioma = "";
    tipo = "";
    calidad = 0;
    link = "";
    imagenLogo = null;
    imagenIdioma = null;
    imagenCalidad = null;
    context = ctx;
}