How can I make the image disappear in Processing - image

Question

I'm using Processing 3.0.1 which is the latest version.
I successed to display the image when I pressed a certain key.
For example, when I press key 'a', then the image will be displayed.
I also want to make the image disappear when I press another key.
However, I can't find a way to do this.
If anyone knows how to do this, please help me
Here is the code
PImage Onepiece1, Onepiece2;
void setup(){
size(600,600);
Onepiece1 = loadImage("Onepiece1.jpg");
Onepiece2 = loadImage("Onepiece2.jpg");
}
void draw(){
}
void showimage1(){
image(Onepiece1,10,10);
}
void keyPressed(){
if(key == 'a'){
showimage1();
}
else if(key == 'b'){
// I want to make the image disappear when I press 'b'
}
println(key);
}

Answer 1

For this simple scenario #Majlik suggestion is ok, but usually it's not a good idea to draw in callback functions like keyPressed(). Instead use a flag to drive drawings in draw(), like:
Untested
PImage Onepiece1, Onepiece2;
boolean showimage = false;
void setup(){
size(600,600);
Onepiece1 = loadImage("Onepiece1.jpg");
Onepiece2 = loadImage("Onepiece2.jpg");
background (255);
}
void draw(){
background (255);
if(showImage){
showImage1();
}
}
void showimage1(){
image(Onepiece1,10,10);
}
void keyPressed(){
if(key == 'a'){
showImage = true;
}
else if(key == 'b'){
showImage = false;
}
println(key);
}

Answer 2

For the simple scenario like this you just need to redraw image with anything. Best practice is to use background() function. So your reaction to pressing b could look like:
if(key == 'b'){
background(99);
}
Also it is good practice to have specified same background color at the beginning inside setup() function:
void setup(){
size(600,600);
...
background(99);
}