Develop Reference

Xamarin.Android random number picks same number multiple times

I am making an app with Xamarin Android. It has 4 turns, and I want a random picture+sound to display in every turn. So far so good, but now I want to make it in a way that it won't show the same picture+sound(the same random number) twice. I have tried some codes from other treads, but unfortunately that did not work.
Following is what I tried from the other treads:
if (ActivityGame.playing == false)
{
List<int> alreadyGuessed = new List<int>();
Random randomSound = new Random();
int theSound = randomSound.Next(1, 5);
while (alreadyGuessed.Contains(theSound))
theSound = randomSound.Next(1, 5);
alreadyGuessed.Add(theSound);
return theSound;
}

You declare the alreadyGuessed list inside the if-branch. So, every time you get in that if branch, the program creates a new, empty list named alreadyGuessed.
You should make alreadyGuessed a member variable of your ActivityGame class, so it will retain the values already used.

Changing activity background by path

I try to change the background of my Activity ( onCreate ) randomly. It stucks in the the last step ... show it. Maybe someone has an idea for me.
I created an array within a xml file which contains 5+ drawable's - it looks like this ..
<array name="backgrounds">
<item>#drawable/bg1_320x480</item>
<item>#drawable/bg2_320x480</item>
<item>#drawable/bg3_320x480</item>
<item>#drawable/bg4_320x480</item>
<item>#drawable/bg5_320x480</item>
<item>#drawable/bg6_320x480</item>
</array>
Within my main activity, I get one random element out of the array ...
String[] mTempArray = getResources().getStringArray(R.array.backgrounds);
int iMin = 0;
int iMax = 5;
int randomIndex = iMin + (int) (Math.random() * iMax);
String resPath = mTempArray[randomIndex];
resPath return me (e.g.) res/drawable-hdpi/bg4_320x480.png. From this point on, I found a lot of solutions, but nothing brings me to succes.
What is the last point to set / change / overwrite the background?

A resource ID is just an integer--there's no need to deal with strings. You can use something like this
int[] imageIds = new int[] { R.drawable.bg1, R.drawable.bg2, ... };
, pick a random element, and set it as your background. Not sure if you can encode the array of resource IDs in xml.

How to assign values from an array to textviews in android

I have 4 textview such as t11,t12,t13,t14 and I have also 4 value in array val[4].
I want to store these values randomly in textviews. but I am getting little problem.
I have done following code:
TextView t11,t12,t13,t14;
Random r = new Random();
for (int i = 0; i < val.length; i++) {
int val[4]=r.nextInt(10);
Log.d("horror", "Randm Array of VAL:" +val[i]);
}
In the Log,there are 4 values displayed but how to display them in textviews.
I have coded but it does not work properly.
t1[i+1].setText("" +val[i]);
and
In this case,values are properly displayed, but i want to do code optimization.
t11.setText("" +val[0]);
t12.setText("" +val[1]);
t13.setText("" +val[2]);
t14.setText("" +val[3]);
Thanks in advance.

Every time you loop in for, you create another integer array. Take the definition of val out of the for loop.

you can store their references inside an array , it won't create new objects. so this should do the job
TextView [] textviews = {t11,t12,t13,t14};
for(int i =0;i<textviews.length;++i){
textviews[i].setText(val[i]);
}

For your TextView use something like,
TextView [] tv = {t11,t12,t13,t14};
and use tv for other going stuff... So now, you can getting it work by,
tv[i+1].setText("" +val[i]);

android dynamical binding

I want to work dynamically therefore I want to bind text views dynamically I think an example would explain me the best
assuming I want to bind 7 image views i can do it like this :
Country = (EditText)findViewById(R.id.CountryEditText);
City = (EditText)findViewById(R.id.CityEditText);
LivinigCreture = (EditText)findViewById(R.id.LivingCretureE);
Nature =(EditText)findViewById(R.id.NatureEditText);
Inanimate = (EditText)findViewById(R.id.InanimateEditText);
KnowenPersonality = (EditText)findViewById(R.id.KnowenPersonalityEditText);
Occupation = (EditText)findViewById(R.id.OccupationEditText);
but lets change 7 with NUMOFFILEDS as a final where i want to do the previous ?
myImages = new ImageView [7];
for (int i = 0; i<7;i++,????)
myImages[i] = (ImageView)findViewById(R.id.initialImageView01);
notice : in my R file the R.id.initialImageView01 - R.id.initialImageView07 are not generate in a cont gap between them therefore I don't know how to make this architecture possible .
and if there's a way can someone show me an example how to work dynmiclly (like using jsp on android combined way or something ?)
id its possiable to do so constant times is it possible to build an the same xml constant num of times like jsp does
thank u pep:)

You can store the IDs themselves in an array at the beginning of your Activity; that way you'll only need to write them once and you can index them afterwards.
Something like:
int[] initialImageViewIds = {
R.id.CountryEditText,
R.id.CityEditText,
R.id.LivingCretureE,
R.id.NatureEditText,
R.id.InanimateEditText,
R.id.KnowenPersonalityEditText,
R.id.OccupationEditText
};
Then you can access them with:
myImages = new ImageView [7];
for (int i = 0; i<7;i++) {
myImages[i] = (ImageView)findViewById(initialImageViewIds[i]);
}
If that's not enough and you really want to get the IDs dynamically, I suppose you can use reflection on the R.id class, possibly with something like R.id.getClass().getFields() and iterate on the fields to check if their names interest you. Check reference for the Class class, too.

Android: Set a random image using setImageResource

I need a help with setting a random image using setImageResource method.
In the drawable folder, I have a jpeg file named photo0.jpg, photo1.jpg...photo99.jpg.
And the following code works:
int p = R.drawable.photo1;
image.setImageResource(p);
The above will display photo1.jpg but I want to show a random image.
I tried the following but it doesn't work.
String a = "R.drawable.photo";
int n = (int) (Math.random()*100)
String b = Integer.toString(n);
String c = a+b;
int p = Integer.parseInt(c);//checkpoint
image.setImageResource(p);
It seems like the string "R.drawable.photoXX" isn't being changed to integer at the checkpoint.
Could someone please teach me a right code?
Thank you in advance.

Strings are pretty much evil when it comes to work like this due to the overhead costs. Since Android already provides you with integer id's I would recommend storing all of them to an int array and then using a random number for the index.
The code would look something like this:
int imageArr[] = new int[NUM_IMAGES];
imageArr[1] = R.drawable.photo;
//(load your array here with the resource ids)
int n = (int)Math.random()*NUM_IMAGES;
image.setImage(imageArr[n]);
Here we have a pretty straight forward implementation and bypass all the creation and destruction that occurs with the string concats.

maybe the error is here
int n = (int) (Math.random()*100)
put % not * Like this
int n = (int) (Math.random()%100)
to get all numbers under 100