Question

i am trying to display a random string each time a button is pressed from a set of strings defined in strings.xml . this is an example of the strings ID’s

<string name="q0">
    <string name="q1">
    <string name="q2">
    <string name="q3">
    <string name="q4">

java code for getting a random string.

private static final Random rgenerator = null;

    int RandomQ = R.string.q0  (rgenerator.nextInt(5) + 1);
    String q = getString(RandomQ);

if i try to use this java code i get an error at “q0” in R.string.q0 which is The method q0(int) is undefined for the type R.string if i try to use the quick fix and create a method, it works. but it wont let me save or run the app because it replaces my create method and shows this message

R.java was modified manually! Reverting to generated version!

thanks for reading.

Answer 1

You can define your strings in an array which will help simplify this task (res/values/array.xml):

<string-array name="myArray"> 
    <item>string 1</item> 
    <item>string 2</item> 
    <item>string 3</item> 
    <item>string 4</item> 
    <item>string 5</item>
</string-array> 

You can then create an array to hold the strings and select a random string from the array to use:

private String[] myString; 

myString = res.getStringArray(R.array.myArray); 

String q = myString[rgenerator.nextInt(myString.length)];

Example code:

package com.test.test200;

import java.util.Random;

import android.app.Activity;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.TextView;

public class Test extends Activity {
/** Called when the activity is first created. */

    private String[] myString;
    private static final Random rgenerator = new Random();

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);


    Resources res = getResources();

    myString = res.getStringArray(R.array.myArray); 

    String q = myString[rgenerator.nextInt(myString.length)];

    TextView tv = (TextView) findViewById(R.id.text1);
    tv.setText(q);
}
}