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Index › Programming Questions & Help › Syntax Questions › noob: Is there a way to click to remove something

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noob: Is there a way to click to remove something? (Read 1078 times)

Lenticular

noob: Is there a way to click to remove something?
Aug 24^th, 2009, 4:29pm

When I click on the top square, the bottom square appears.

How can I click on the bottom square to make it disappear? I don't want to paint white over the top of it. I want the bottom square to be removed. Is there a function I don't know about or can I modify the code I have? Thanks.

boolean button = false;

int x = 20;
int y = 20;
int w = 100;
int h = 20;

void setup() {
size(200,200);
background(255);
}

void draw() {
stroke(0);
fill (140,160,220);
rect(x,y,w,h);

if (mouseX > x && mouseX < x+w && mouseY > y && mouseY < y+h && mousePressed) {
button = true;
} else {
button = false;
}

if (button) {
stroke(0);
fill(180,190,250);
rect(20,60,160,120);
}
}

ben_hem

Re: noob: Is there a way to click to remove something?
Reply #1 - Aug 24^th, 2009, 5:36pm

right now you say:

"if the mouse is inside the top rect and pressed, button=true"

... so you need to add a statement for:

"if the mouse is inside the bottom rect, and the mouse is pressed, and button==true, button=false."

it can all go inside "void mousePressed(){ }" instead of draw(), for simplicity...

Cedric YaBB Moderator Offline Posts: 1838	Re: noob: Is there a way to click to remove something? Reply #2 - Aug 24^th, 2009, 5:57pm please dont start every topic with noob: it confuses me when reading the topics with my RSS Reader
	twitter.com/CedricKiefer

Lenticular

Re: New: Is there a way to click to remove something?
Reply #3 - Aug 24^th, 2009, 6:58pm

I don't fully understand. I modified the code below. I tried ( == ) but received a syntax error so I changed it back. Does the location of where the code goes have some barring on the out come?

boolean button = false;

int x = 20;
int y = 20;
int w = 100;
int h = 20;

void setup() {
size(200,200);
background(255);
}

void draw() {
stroke(0);
fill (140,160,220);
rect(x,y,w,h);

if (mouseX > x && mouseX < x+w && mouseY > y && mouseY < y+h && mousePressed) {
button = true;
} else {
button = false;
}

if (mouseX > 20 && mouseX < 160 && mouseY > 60 && mouseY < 120 && mousePressed) {
button = true;
} else {
button = false;
}

if (button) {
stroke(0);
fill(180,190,250);
rect(20,60,160,120);
}
}

I will try to use New or something different instead of noob: from now on.

Cedric

Re: noob: Is there a way to click to remove something?
Reply #4 - Aug 24^th, 2009, 7:18pm

what i meant was, not to start every topic with the same word, cause i can only read the first words in my rss reader

anyway, first thing in your code that makes it hard for you to find the problem is, you dont use background in draw, so even if the box disappears again, it would still be there...

i changed the code a bit.
boolean button = false;

int x = 20;
int y = 20;
int w = 100;
int h = 20;

void setup() {
size(200,200);
background(255);
}

void draw() {
background(255);
stroke(0);
fill (140,160,220);
if (mouseX > x && mouseX < x+w && mouseY > y && mouseY < y+h )fill(150,190,250);
rect(x,y,w,h);
if (button) {
stroke(0);
fill(180,190,250);
rect(20,60,160,120);
}
}
void mouseClicked() {
if (mouseX > x && mouseX < x+w && mouseY > y && mouseY < y+h ) {
button = !button;
}
}

twitter.com/CedricKiefer

Lenticular YaBB Newbies Offline Posts: 36	Re: noob: Is there a way to click to remove something? Reply #5 - Aug 24^th, 2009, 8:05pm Thanks for your response. Your code is shorter. You removed (mousePressed) and the (else) statement. Just when I was starting to understand the rules, the rules seem to change. Plus the first (if) statement is missing curly braces and your code still works. That's a new one on me.

Cedric

Re: noob: Is there a way to click to remove something?
Reply #6 - Aug 24^th, 2009, 8:16pm

yes, that confused me too when i first saw it. Using if without braces takes care of the following line but only the following, so if you just use one command like fill in my case, you can do it that way. its just shorter. but you can remove that, its just for changing color on mouseover. i thought its useful

And what i also changed was i changed from mousePressed to mouseclick. MousePressed executes as long as the mouse is pressed. Mouse Click only once. Changing that, i was able to use button=!button; instead of the if else.
its like saying, change button to the opposite and not
if positive turn negativ, if negativ turn positiv.
thats much shorter and works too...

and to be honest i didnt understand what your second if was for, i removed it...

twitter.com/CedricKiefer

Lenticular

Re: noob: Is there a way to click to remove something?
Reply #7 - Aug 24^th, 2009, 8:40pm

I agree changing color on mouseover is useful, I was going to get to that after I developed more experience.

I will haft to study up on the differences between mousePressed and mouseClicked. It looks like mouse clicked is more efficient.

I originally had only one if statement for a button to draw a rect. I added the second if to remove the rect., but didn't understand how to hook it up.

Cedric YaBB Moderator Offline Posts: 1838	Re: noob: Is there a way to click to remove something? Reply #8 - Aug 24^th, 2009, 8:44pm if you go for a click like in your case mouseclicked is the better choise, but i can think of other ways, like drawing when you should use mousePressed.
	twitter.com/CedricKiefer

ben_hem

Re: noob: Is there a way to click to remove something?
Reply #9 - Aug 24^th, 2009, 8:45pm

== asks "is this true," and = says "make this true." So:
(3 == 4); // returns "false"

to test if a boolean is "true" (in the case of your 'button' boolean), you can say:

if (button==true)... // this is saying "does button equal true? then return true."
or
if (button) ... // since "button==true" will return either true if true, or false if false, this simplifies your little tautology a bit :P
or
if (button != false)...// "!" = "NOT."

Cedric's example uses the same clickable to toggle the other on and off. The statement "button = !button" means "set button to the opposite (!) of button."

If you want your large button to disappear when clicked, your conditional will look something like this:

if ( (mousePressed) && (mouseInLowerArea) && (button) ) button=false;

(of course if you're putting it all in mousePressed or mouseClicked then you don't need to ask whether the mouse is pressed. The other reason this is good practice is that you probably don't want the user to be able to trigger your clickable by clicking outside and then dragging across it.)

--Ben

Lenticular YaBB Newbies Offline Posts: 36	Re: noob: Is there a way to click to remove something? Reply #10 - Aug 24^th, 2009, 9:18pm I see what your saying, like holding the mouse down when your drawing. At the moment I am on the edge of my territory of understanding. I will need some time to study up on what you guys have said and then I will try some more experiments. Thanks for your help.

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