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ganderous

is this possible

in General Discussion • Other • 2 years ago

Hi im new to processing and i was wondering if this is possible and whether or not someone can point me in the right direction on how to do it.

what i want to do is link pictures that i have made to an RSS feed that gives a temperature reading

so i want to link "image 1" to the amount "1"

"image 2" to the amount "2"

" " " " "etc etc etc" " "

i have the rss feed details and have used it in flash just to test it and i can get it to come up with the amounts 1 2 3 4 and so on

but what i want to do is do this in processing and instead of it just coming up with the amounts i want it to come up with a picture

like a visual thermometer (thats the best way i can describe it although its going to be a picture of somat else)

if anyone knows how i could do it i would greatly appreciate some help as i only have very very basic knolledge of processing

1

Replies(16)

blindfish

blindfish

Re: is this possible

2 years ago

Well the simplest solution would be to use conditions to check the value and display the appropriate image depending on the value. A more elegant solution would be to put the images into an array and use the value to reference the index of the image to display...

But maybe your first problem is accessing the RSS feed from Processing? In that case have a look at the Libraries section.

ganderous

Re: is this possible

2 years ago

i think the bit im struggling most is getting the rss feed into processing

i cant get it to work :(

blindfish

blindfish

Re: is this possible

2 years ago

What have you tried? Did you look for a suitable Library?

Note that you may run across cross domain security issues in the exported applet, so you'll need to look into signing the applet (though shouldn't need to worry about that when testing locally)... Which reminds me: I was going to look at updating the tutorial on that :/

ganderous

Re: is this possible

2 years ago

i am very new to processing and have managed to get it to display an image.

i dont know where to start when it comes to getting the rss feed into the program

i have done a search and came across a piece that someone had done on the internet that displays the feeds

i tried to copy and paste that into processing and it sort of worked but i dont think that was the right way to go about it

i have a rss feed that updates everytime the temperature changes

so i have a feed that is displaying 2 numbers at the moment its 11 which is 11degrees C but all it shows is the figure

i can get that to display in flash

what i want is to get that to display in processing as processing is worded all different and i dont really understand the script

i need this for my degree work

if i can get it to read the rss feed in processing then all i need to do is get it to instead of display the amount it will open a window and display an image that i have linked to that amount

Im going to have to see if someone at my university knows how to do it because my lecturer said it is possible to do

PhiLho

PhiLho

Re: is this possible

2 years ago

Show us the current state of your best attempt, so we can see what is wrong.
Out of the blue, I would suggest to try and use loadStrings() (or, perhaps better, loadBytes()) with the URL of the RSS feed, then parse it with Processing's XML library. Well, actually you can build XMLElement with the URL of the feed too.

blindfish

blindfish

Re: is this possible

2 years ago

The romeFeeder library claims to be able to parse RSS feeds; though the online example I tried didn't appear to work... Still might be worth a try ;)

ganderous

Re: is this possible

2 years ago

this is what i have so far

import processing.xml.*;

void setup()
{
String url = " http://newsrss.bbc.co.uk/weather/forecast/8/ObservationsRSS.xml";
XMLElement document = new XMLElement(this, url);
XMLElement[] stories = document.getChildren("channel/item");
XMLElement[] headline;
for(int i=0; i<stories.length ; i++) {
    headline = stories[i].getChildren("title");
    if(headline.contains("1°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("2°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("3°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("4°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("5°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("6°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("7°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("8°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("9°C")) {
      loadImage("test.jpg")
    }
    else if(headline.contains("10°C")) {
      loadImage("test.jpg")
    }
    print(headline[0]);
}
}

ganderous

Re: is this possible

2 years ago

the test images are just me trying to display a image if the feed displays 1°C or 2 etc 3 etc

1°C is equal to 1degreeC i cant do the little symbol but that ° represents it in the rss feed

the error message im getting is

Syntax error, maybe a missing semicolon?

ganderous

Re: is this possible

2 years ago

ok so i have added the semi colon DOH! silly mistake but now im getting another issue

Cannot invoke contains (string) on the array type XMLElement[]

blindfish

blindfish

Re: is this possible

2 years ago

getChildren() returns an array of XMLElements, hence the error. Looking at the XML I guess it seems safe to assume that there will only ever be one 'title', but the getChildren() method is generic and also needs to handle the case where there are multiple children of the same type. To be on the safe side I'd check the length of the returned array - which you've set to the variable 'headline' - and then reference the first element of the array. However you may find you also need to call getContent() on the XMLElement. Sorry not 100% definite as I've never used the library, but you probably need something along the lines of this untested code:

XMLElement[] headlines; // note I've made this plural to indicate there can potentially be more than one
for(int i=0; i<stories.length ; i++) {
headlines = stories[i].getChildren("title");
// precaution check the array length to avoid nullPointerExceptions
if(headlines.length > 0) {
XMLElement titleXML = headlines[0]; // let's assume a single title
String title = titleXML.getContent(); // get the content as a String
// Now you've got a string you can start doing your test
if(title.contains("1°C")) {
loadImage("test.jpg")
}
// etc...
}
}

ganderous

Re: is this possible

2 years ago

i have spoken to a tutor of mine after showing him this.

PImage a;
import processing.xml.*;
void setup() {
size(200, 200);
String url = " http://newsrss.bbc.co.uk/weather/forecast/8/ObservationsRSS.xml";
XMLElement document = new XMLElement(this, url);
XMLElement[] stories = document.getChildren("channel/item");
XMLElement[] headline;
for(int i=0; i<stories.length ; i++) {
    headline = stories[i].getChildren("title");
    if (headline.contains("1°C"));
    loadImage("blank.JPG");
}
if(headline.contains("2°C")) {
    loadImage("blank.JPG");
}
}

he said i need to convert the XMLElement into a string

but i dont know how to do that :S

he said i could use something like this

String gerald = headline[0].toString();

then change the other lines to

gerald.contains("2°C");
etc etc etc etc

but i dont know where i woudl put the

String gerald = headline[0].toString();

ganderous

Re: is this possible

2 years ago

OK THIS WORKS!

PImage a;
import processing.xml.*;
void setup() {
size(200, 200);
String url = " http://newsrss.bbc.co.uk/weather/forecast/8/ObservationsRSS.xml";
XMLElement document = new XMLElement(this, url);
XMLElement[] stories = document.getChildren("channel/item");
XMLElement[] headline;
for(int i=0; i<stories.length ; i++) {
    headline = stories[i].getChildren("title");
    if (headline.length > 0 ) {
      XMLElement titleXML = headline[0];

      String title = titleXML.getContent();
    a = loadImage("blank.JPG");
}
if(headline.length > 1) {
    a = loadImage("blank.JPG");
}
}
}
void draw() {
    image(a, 0 , 0);
}

BUT THIS WILL SHOW THE SAME IMAGE AS IT WILL ALWAYS BE GREATER THAN "0" OR AM I WRONG?

THANKS FOR HELP SO FAR!

ganderous

Re: is this possible

2 years ago

this is the stage i am at now

PImage a;
PImage b;
PImage c;
PImage d;
PImage e;
import processing.xml.*;

void setup() {
size(200, 200);
a = loadImage("blank.JPG");
b = loadImage("blank2.JPG");
c = loadImage("blank3.JPG");
d = loadImage("blank4.JPG");
e = loadImage("blank5.JPG");
String url = " http://newsrss.bbc.co.uk/weather/forecast/8/ObservationsRSS.xml";
XMLElement document = new XMLElement(this, url);
XMLElement[] stories = document.getChildren("channel/item");
XMLElement[] headline;
for(int i=0; i<stories.length ; i++) {
    headline = stories[i].getChildren("description");
    if ((headline.length > 0) && (headline.length < 2)) {
      XMLElement titleXML = headline[0];

      String title = titleXML.getContent();
    a = loadImage("blank.JPG");
}
else if((headline.length > 1) && (headline.length < 3)) {
    b = loadImage("blank2.JPG");
}
    else if((headline.length > 2) && (headline.length < 4)) {
    c = loadImage("blank3.JPG");
}
else if((headline.length > 3) && (headline.length < 5)) {
    d = loadImage("blank4.JPG");
}
else if((headline.length > 4) && (headline.length < 6)) {
    e = loadImage("blank5.JPG");
}
print(headline[0]);
}
}
void draw() {
image(a, 0, 0);
image(b, 0, 0);
image(c, 0, 0);
image(d, 0, 0);
image(e, 0, 0);
}

but i dont want to take the data from the length of the description

i just want to take say the 14th character in the description which is the number

i want to make it so that it takes the 14 and 15th characters as the number is not always between 0 and 9 sometimes it is 10 or above

any ideas?

PhiLho

PhiLho

Re: is this possible

2 years ago

Why did you changed from contains() to length? How the size of the array matters here? Why are you loading the images twice? Consider using an array instead than a bunch of similar variables. Search the patterns in your code to avoid (nearly) duplicate lines.

blindfish

blindfish

Re: is this possible

2 years ago

I think you've misunderstood the purpose of checking the array length in the code I posted, even though I added a comment to explain it:

headlines = stories[i].getChildren("title");
// precaution check the array length to avoid nullPointerExceptions
if(headlines.length > 0) {
XMLElement titleXML = headlines[0]; // let's assume a single title
}

When you're dealing with data coming from an external source you don't have any control over it, so it's good practice to take precautions like this. The test against headlines.length is to make sure the XML did in fact contain a title element so that there's no risk of an error when you try and access it with headlines[0] and then extract the content. Actually I'm surprised that your tutor is saying you should 'convert' to a String - to be more precise what you actually need to do is extract the content of the XML tag, but maybe I'm being pedantic.

Anyway, I'm guessing you don't properly understand Arrays. Spend some time, perhaps experimenting in separate sketches, to understand them: they're very useful ;)

ganderous

Re: is this possible

2 years ago

i dont know im all confused lol

i think im further with it than i was lol i have about 5 months to get this right lol

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