Making a snapshot of the current parameter state

We will implement a simple but useful mechanism for saving and loading the parameters' states. The code used in the examples will be based on the previous recipes.

Getting ready

Let's say we have a variable that we are changing frequently. In this case, it will be the color of some element we are drawing and the main class will have the following member variable:

ColorA mColor;

How to do it...

We will use a built-in XML parser and the fileDrop event handler.

1. We have to include the following additional headers:

   #include "cinder/params/Params.h"
   #include "cinder/ImageIo.h"
   #include "cinder/Utilities.h"
   #include "cinder/Xml.h"

2. First, we implement two methods for loading and saving parameters:

   void MainApp::loadParameters(std::string filename)
   {
     try {
       XmlTree doc( loadFile( fs::path(filename) ) );
       XmlTree &generalNode = doc.getChild( "general" );
   
           mColor.r = generalNode.getChild("ColorR").getValue<float>();
           mColor.g...