first time here on stackoverflow and first time scripting in flashCS6.
ill get down to it - the only lang ive done is html and a bit of css. I tried learning java, but gave up since i realised im making flash games so might as well just do AS3. Its pretty similar and not at all at the same time.
As my first original program (i did a tutorial of pong from a website before, got to know a bit about functions and event handlers[http://as3gametuts.com/2011/03/19/pong-1/]), im trying to create a calculator, and what want to know is how i can return the values from two input fields, put them into a logic calculator (say input a is 1 and input b is 2, and there are four functions, each attached to an event listener for the 4 mathematical operations, and i press addition so the calculator goes 2+1=3)
main question here, how do i get the outut text field to display the answer. In java i just used system.out.println(inputA + inputB).
Here i tried to do out.text = ( a + b) (where out is output , a is input and b is input 2)
Here is the code i have so far:
a is input 1, b is input 2
Out is output
and mul, add, sub and div are symbols containing dynamic test fields with instance names adn, sub, mul and div respectively. The symbol instances are the same as the test instances) Ex: i have a text field that says addition, its instance name is adn, then i convert it to a symbol and make its instance name adn as well.
a.text.restrict = "0-9";
b.text.restrict = "0-9";
mul.addEventListener(MouseEvent.CLICK, output);
adn.addEventListener(MouseEvent.CLICK, addition);
sub.addEventListener(MouseEvent.CLICK, subtraction);
div.addEventListener(MouseEvent.CLICK, division);
a.addEventListener(TextInput,input);
b.addEventListener(TextInput,input);
function output ():void
{
out.text=("test to see if output works")
}
function input (e:TextInput)
{
}
function multiplication (e:MouseEvent)
{
}
function addition (e:MouseEvent)
{
}
function subtraction (e:MouseEvent)
{
}
function division (e:MouseEvent)
{
}
thanks guys, and cheers! Also, ill appreciate if anyone can link me to a good video or text tutorial (series) for AS3 introduction. My main focus is to be making PC games and not apps, so keep that in mind.
Check This Out
Also, don't forget to convert value to string, that may be neccessary:
out.text = String(a + b);
Since a text field will give you the input typecast as a string you will need to type cast them to type Number or type int before you can do any kind of math function on them.
And if you want to create a more complex calculator I would suggest you read up on the Math class
function subtraction (e:MouseEvent)
{
var result:Number = Number(a.text) - Number(b.text)
out.text = String(result)
}
Related
i know this might be simple but i have been searching everywhere for a fix but i just cannot find it!
i want to make something like a health #, so when you press whatever button the dynamic text # will go up or down. on my test project i have two layers, the first with the following code
var hp:Number = 100;
health.text = String hp;
hp being the variable, and health being the dynamic text. then i have the next layer with the button with:
function button(e:MouseEvent):void
{
hp -= 10;
}
without that second chunk of code, the dynamic text will appear, but once that is added it will disappear and the button is function-less.
how do i make this work??? once again sorry if this is a dumb question, i'm just very stumped.
The accepted answer is good, but I wanted to point out that your original code was actually very close to being correct, you just needed parenthesis:
health.text = String(hp);
For most objects String(object) and object.toString() has the same effect, except that object.toString() throws an error if object is null (which could be desirable or undesirable, depending on what you expect it to do).
This is not correct:
health.text = String hp;
use:
health.text = hp.toString();
and:
function button(e:MouseEvent):void
{
hp -= 10;
health.text = hp.toString();
}
I'm trying to do some re-factoring on my charts to make them re-usable using this as a guide: http://bost.ocks.org/mike/chart/
I'm having problems drawing the lines in my multi-line graph though - specifically passing the data to the x and y values. If I hard code the element names it works, but if I try to use the xValue and yValue objects this does not work. I'm assuming that this is because I'm trying to call a function within the parameter of an other object, but I'm not sure how to get around this. In the exmaple Mike uses d[0] and d[1], but this won't work with JSON data (or I'm not sure how to make it work).
I've posted this JSFiddle so you can see the code. The problem lines are 125 to 131 which in turn is being called from line 165.
var main_line = d3.svg.line()
.interpolate("cardinal")
// Hard coding the elements works
//.x(function(d) { return main_x(d.date); })
//.y(function(d) { return main_y(d.buildFixTime); });
// Passing xValue and yValue does not work
.x(function(d) { return main_x(xValue); })
.y(function(d) { return main_y(yValue); });
http://jsfiddle.net/goodspeedj/fDyLY/
Thank you in advance.
You need to redefine your accessor method within .x() and .y(). The accessor method defines the way that a datum is pulled out of the data that is bound to the selection that you call the line generator on.
Suppose you have a relatively flat data structure such as the following.
data = [{x : 1, y : 2}, {x:1, y:3}, {x:4, y:5}];
You then bind the data to a selection with the following statement
d3.select("body").datum(data).append("path").attr("d",lineGenerator);
Quite a bit is going on underneath this statement. I'll give you a bit more of a walkthrough after showing you a commonly used example.
The important aspect to understand is that similarly to other calls in d3 such as
var exampleRectangles = d3.select("body")
.data(data).enter()
.append("rect")
.attr("width",2)
.attr("height", 3)
.attr("x",function(datum){return datum.x}) // pay attention to this line
.attr("y",0);
d3 is implicitly iterating over each element in your data. For each datum in your data array, in this case there is a total of three datum, you are going to add a rectangle to the dom.
In the line that I tell you to pay attention to you notice that you're defining an anonymous (unnamed) function. What is that datum parameter coming from? It's implicitly being passed to your anonymous function.
So each rectangle has it's own corresponding datum {x : 1, y : 2}, {x:1, y:3}, {x:4, y:5} respectively. Each rectangle's x coordinate is defined by the respective datum.x attribute. Under the sheets, d3 is implicitly looping over the data array that you've defined. A similar approach to the example d3 code could be written as above.
for (var i = 0; i < data.length; i++)
{
d3.select("body").append("rect")
.attr("width",2)
.attr("height", 3)
.attr("x",data[i].x)
.attr("y",0);
}
This follows from the notion of data driven documents (d3). For each item added (a rectangle in the above example a piece of data is tied to it. In the above example you see that there is something kind of similar to your .x() and .y() accessor functions :
.attr("x",function(datum){return datum.x})
This function is telling d3 how to filter over the total datum that's being passed to the .attr() accessor method.
So, you need to determine which data you need to get a hold of to make your .attr("d", lineGenerator)call make sense. The difference between your.datum(data)call and the typical.data(data)call is that instead of parceling the data that's being passed to.data(data)`, the whole array is given as a single piece of data to the line generator function (similar to main_line(data), wherein it will again implicitly loop over the points to construct your path.
So, what you need to do is determine what a single datum will be defined as for your function to operate on.
I'm not going to define that as I don't seem to know quite which information you are operating on, but I would hazard a guess at something like.
.x(xAccessor)
.y(yAccessor)
function xAccessor(datum)
{
return xScale(datum._id.month);
}
function yAccessor(datum)
{
return yScale(datum.buildFixTime);
}
The way you have it set up, xValue and yValue are functions; you have to actually execute them on something to get a value back.
.x(function(d) { return main_x( xValue(d) ); })
.y(function(d) { return main_y( yValue(d) ); });
If you weren't using a scale, you could use
.x(xValue)
.y(yValue);
but only because if you pass in a function d3 executes it for you with the data as a parameter. And that only works for d3 methods that expect functions as possible input -- the scale functions expect data values as input.
I wrote a long piece work for another user last week that you may find useful, explaining methods that accept functions as parameters.
I guess a step back is in order. My original question is at the bottom of this post for reference.
I am writing a word guessing game and wanted a way to:
1. Given a word length of 2 - 10 characters, randomly generate a valid english word to guess
2.given a 2 - 10 character guess, ensure that it is a valid english word.
I created a vector of 9 objects, one for each word length and dynamically created 172000
property/ value pairs using the words from a word list to name the properties and setting their value to true. The inner loop is:
for (i = 0; i < _WordCount[wordLength] - 2; i)
{
_WordsList[wordLength]["" + _WordsVector[wordLength][i++]] = true;
}
To validate a word , the following lookup returns true if valid:
function Validate(key:String):Boolean
{
return _WordsList[key.length - 2][key]
}
I transferred them from a vector to objects to take advantage of the hash take lookup of the properties. Haven't looked at how much memory this all takes but it's been a useful learning exercise.
I just wasn't sure how best to randomly choose a property from one of the objects. I was thinking of validating whatever method I chose by generating 1000 000 words and analyzing the statistics of the distribution.
So I suppose my question should really first be am I better off using some other approach such as keeping the lists in vectors and doing a search each time ?
Original question
Newbie first question:
I read a thread that said that traversal order in a for.. in is determined by a hash table and appears random.
I'm looking for a good way to randomly select a property in an object. Would the first element in a for .. in traversing the properties, or perhaps the random nth element in the iteration be truly random. I'd like to ensure that there is approximately an equal probability of accessing a given property. The Objects have between approximately 100 and 20000 properties. Other approaches ?
thanks.
Looking at the scenario you described in your edited question, I'd suggest using a Vector.<String> and your map object.
You can store all your keys in the vector and map them in the object, then you can select a random numeric key in the vector and use the result as a key in the map object.
To make it clear, take a look at this simple example:
var keys:Vector.<String> = new Vector.<String>();
var map:Object = { };
function add(key:String, value:*):void
{
keys.push(key);
map[key] = value;
}
function getRandom():*
{
var randomKey = keys[int(Math.random() * keys.length)];
return map[randomKey];
}
And you can use it like this:
add("a", "x");
add("b", "y");
add("c", "z");
var radomValue:* = getRandom();
Using Object instead of String
Instead of storing the strings you can store objects that have the string inside of them,
something like:
public class Word
{
public var value:String;
public var length:int;
public function Word(value:String)
{
this.value = value;
this.length = value.length;
}
}
Use this object as value instead of the string, but you need to change your map object to be a Dictionary:
var map:Dictionary = new Dictionary();
function add(key:Word, value:*):void
{
keys.push(key);
map[key] = value;
}
This way you won't duplicate every word (but will have a little class overhead).
I'm trying to create a flash application that will keep track of user generated values. The app should basically allow the user to input the name of the item and it's cost. The total costs should then be added up to show a total value to the user. I can probably figure out how to add the values together, but I'm not really sure how to allow the user to create a list and then allow the user to save it. Can anyone point me towards a tutorial or point me in the right direction?
I am using variables to add user inputed numbers to come up with a total. The first problem is that actionscript 3.0 does not allow variables for texts. I just converted it to 2.0 to fix this. The second problem, is when I test the app and put in my values and click submit, I get NaN in the total values field. Is there a reason why it wouldn't add the values?
Here is the code I used for the submit button:
on (release) {
total = Number(rent) + Number(food) + Number(travel) + Number(entertainment) + Number(bills);
}
Am I missing anything?
Can I give the input text instance names and then give them variables? How are some ways to go about this?
Thanks for the help!
Have an object array, say for example
var stack:Array = new Array();
Then push the item name and it's cost to that array when user inputs, like
stack.push({item:AAA, cost:xx});
So that you can generate the list whenever you want with that array.
You have to see how this works in code. A list in actionscript could be stored inside an array, vector, dictionary or even an Object.
Var myList:Array = [];
myList.push({name: "item 1", cost: 5 });
myList.push({name: "item 2", cost: 7.5 });
If you want to grab the 'product' of "item 1" from the list, you have to create a function for that, lets call it getProductByName
function getProductByName(name:String):Object
{
for each(var product:Object in myList)
{
if (product.name === name) return product;
}
return null; // no match found
}
You can call that function like this:
var product = getProductByName("item 1");
trace(product.cost); // 5
And you can alter the product, so lets make it more expensive
product.cost += 1;
trace(product.cost); // 6
Have fun! If you are using classes, you would create one for the product, with public name and cost, and in that case you'de better use a vector, to ensure working with the right type.
This is what fixed the issue for me in action script 3.0:
myButton.addEventListener(MouseEvent.CLICK, addThem);
function addThem(e:MouseEvent)
{
totalField.text = String ( Number(field1.text) + Number(field2.text) + ....);
}
I also had to name the instances appropriately.
I am trying to sort big array using actionscript 3.
The problem is that i have to use custom sorting function which is painfully slow and leads to flash plugin crash.
Below is a sample code for custom function used to sort array by length of its members:
private function sortByLength():int {
var x:int = arguments[0].length;
var y:int = arguments[1].length;
if (x > y){
return 1;
}else if (x < y){
return -1;
}else{
return 0;
}
}
Which is called like this:
var txt:Array = ["abcde","ab","abc","a"];
txt.sort(sortByLength);
Please advise me how can this be done faster ?
How to change application logic to avoid Flash plugin crashes during sorting ?
try to use strong typing whenever possible, here tell your function that you are waiting two strings.
you could rewrite your function in two way one fastest than the other if you know that all your element are not null:
function sortByLength(a:String, b:String):int {
return a.length-b.length // fastest way not comparison
}
and if you can have null check for it (this one will put null in front of all element):
function sortByLengthWithNull(a:String, b:String):int {
if (a==null) return -1
if (b==null) return 1
return a.length-b.length
}
If you need super-fast sorting, then it might be worthwhile not using an array at all and instead using a linked-list. There are different advantages to each. Primarily, with a linked-list, index-access is slow, while iterating through the list is fast, and linked-lists are not native to AS3 so you'll have to roll your own.
On the upside, you may well be able to use some of Polygonal Labs' code: http://lab.polygonal.de/as3ds/.
Sorting is very, very fast for nearly-sorted data with a linked list, as this article discusses: http://lab.polygonal.de/2007/11/26/data-structures-more-on-linked-lists/.
This solution gives you lots more work, but will eventually give you lots more sort-speed too.
Hope this helps.
-- additional --
I noticed your question in the comments of another answer about "One question however is unanswered - how to perform greedy computations in Flash without hanging it?"
For this, essentially the answer is to break your computation over multiple frames, something like this:
public function sort():void
{
addEventListener(Event.ENTER_FRAME, iterateSort);
}
private function iterateSort():void
{
var time:int = getTimer() + TARGET_MILLISECONDS_PER_FRAME;
var isFinished:Boolean = false;
while (!isFinished && getTimer() < time)
isFinished = continueSort();
if (isFinished)
removeEventListener(Event.ENTER_FRAME, iterateSort);
}
function continueSort():Boolean
{
... implement an 'atom of sort' here, whatever that means ...
}
sortByLength should have two parameters, shouldn't it? I guess that's what you mean by the arguments array...
This looks fine to me, unless arguments is not a local variable, but instead a member variable, and you're just looking at its [0] and [1] elements on each function call. That would at least produce undesired results.