Question

I’m trying to make a real simple app in which clicking a button has a Toast pop up which displays a random message from an array. The problem isn’t that I can’t get it to work at all, it’s that I can get it to work by creating and listing the array in the activity, but not any of the other ways I’ve read about. So, this code works fine:

package squatingyeti.loveyou.android;


import android.app.Activity;
import android.content.res.Resources;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

import java.util.Random;

public class LoveYouActivity extends Activity {



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

        Button btn1 = (Button)findViewById(R.id.button1);
        btn1.setOnClickListener(btnListener);


    }

    private OnClickListener btnListener = new OnClickListener() {
        public void onClick(View v) {
            showThem();
        }
    };

    private static final Random RANDOM = new Random();

    /**Resources res = getResources();
    String[] love = res.getStringArray(R.array.love_array);
    */


    private static final String[] love = {
        "testone",
        "testtwo",
        "testthree",
        "testfour",
        "testfive",
        "testsix",
        "testseven"
    }; 

    private void showThem() {
        int showLength = love.length;
        String rsn = love[RANDOM.nextInt(showLength)];
        Toast.makeText(getBaseContext(), rsn, Toast.LENGTH_LONG).show();

    }
}

You can see where I commented out the other way I attempt to use the array. If I comment out the array created in the activity and use the “love = res.getStringArray…” portion of the code, the emulator force closes the app. I can start it again, but it loads with a black screen, no button and just the app name at top. I’m not sure why attempting to call the String[] from the arrays.xml file causes this vs. creating the array and writing out each item in the actual activity. Here is the arrays.xml in my values folder for when I use the method that is failing:

    <?xml version="1.0" encoding="utf-8"?>
<resources>
    <string-array name="love_array">
        <item>testone</item>
        <item>testtwo</item>
        <item>testthree</item>
        <item>testfour</item>
        <item>testfive</item>
    </string-array>
</resources>

Lastly, here is the R.java portion pertaining to the array:

public final class R {
public static final class array {
    public static final int love_array=0x7f050000;
}

I mean, this seems really stupid as the app serves no serious purpose other than my messing around and I can make it work. I was just trying to figure out why I can’t make it work the other way when I’ve read that is the correct way.

Thanks!

Answer 1

Very odd. I’m doing the exact same thing in one of my programs without issue:

String[] tableItems = getResources().getStringArray(R.array.settings_menulist_array);

And my the portion from my res/values/strings.xml:

<string-array name="settings_menulist_array">
    <item>Login ID</item>
    <item>Password</item>
    <item>Menu item #3</item>
    <item>Menu Item #4</item>
</string-array>

The only thing I can think is that your R.java file is corrupt in some way.
Try this:

1. Remove the app from the device/emulator.
2. Delete R.Java
3. Perform a Clean (assuming you’re using Eclipse, then Project -> Clean…)

See if that fixes the issue.

* Updated based on testing *
Move the assignment into a method – ie, onResume(). getResources() returns null when outside of a function – this will fix your problem.