Populate Spinner that maps strings to numbers from XML in Android

Question

In my application I need to have Spinner with set of values, for example:

• today
• tomorrow
• after_tomorrow

User chooses one of it and applications send request to server. To send the request i need to encode user's choice as int value:

• Request.TODAY = 0;
• Request.TOMORROW = 1;
• Request.AFTER_TOMORROW = 2;

In UI those value are localized and, more important, could be in different order, depending on locale, for example:

• послезавтра (after_tomorrow)
• завтра (tomorrow)
• сегодня (today)

What I want is to have all that stuff in localizable XML (so localization team will need to edit only XML files, not code):

• String values
• String order

I spent some time thinking on that problem, and my solution is here.

In strings.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="day_today">сегодня</string>
    <string name="day_tomorrow">завтра</string>
    <string name="day_after_tomorrow">послезавтра</string>
    <array name="day_values">
        <item>@string/day_after_tomorrow</item>
        <item>@string/day_tomorrow</item>
        <item>@string/day_today</item>
    </array>
</resources>

In layout.xml:

            <Spinner
                    android:layout_width="fill_parent"
                    android:layout_height="wrap_content"
                    android:id="@+id/day"
                    android:entries="@array/day_values" />

In MyActivity.java:

private int[] dayMap;
private Spinner uiDay;

private final void setupUI(Bundle savedInstanceState) {
    uiDay = (Spinner)findViewById(R.id.day);
    final TypedArray dayValues = getResources().obtainTypedArray(R.array.day_values);
    dayMap = new int[dayValues.length()];
    for (int i = 0; dayMap.length > i; ++i) {
        final int r = dayValues.getResourceId(i, 0);
        // can't use switch() since resources ids not always final since Android 4
        if (R.string.day_today == r) {
            dayMap[i] = Request.TODAY;
        } else if (R.string.day_tomorrow == r) {
            dayMap[i] = Request.TOMORROW;
        } else if (R.string.after_tomorrow == r) {
            dayMap[i] = Request.AFTER_TOMORROW;
        }
    }
    dayValues.recycle();
}

public void submitClicked(View v) {
    final int r = dayMap[uiDay.getSelectedItemPosition()];
    submitDayRequest(r);
}

I see only one bad thing in that solution - TypedArray.getResourceId() returns "resolved" id, so if some redirects will be involved entire "if" will not work.

I want to hear some opinions on that solution and advises on how it can be implemented in other ways.

Thanks!

Update1:

Another solution uses two string arrays in xml file.

strings.xml:

<string-array name="day_entries">
    <item>послезавтра</item>
    <item>завтра</item>
    <item>сегодня</item>
</string-array>
<string-array name="day_values">
    <item>after_tomorrow</item>
    <item>tomorrow</item>
    <item>today</item>
</string-array>

MyActivity.java:

private static final Map<String, Integer> DAYS;

static {
    DAYS = new HashMap<String, Integer>();
    DAYS.put("today", Request.TODAY);
    DAYS.put("tomorrow", Request.TOMORROW);
    DAYS.put("after_tomorrow", Request.AFTER_TOMORROW);
}

private Spinner uiDay;
private String[] dayValues;

private final void setupUI(Bundle savedInstanceState) {
    uiDay = (Spinner)findViewById(R.id.day);
    dayValues = getResources().getStringArray(R.array.day_values);
}

public void submitClicked(View v) {
    final int r = DAYS.get(dayValues[uiDay.getSelectedItemPosition()]);
    submitDayRequest(r);
}

layout.xml:

            <Spinner
                    android:layout_width="fill_parent"
                    android:layout_height="wrap_content"
                    android:id="@+id/day"
                    android:entries="@array/day_entries" />

What do you think about it? Is it better on not than the first one? Maybe other ways to implement such thing?

Answer 1

I would suggest you use the second method. Localization wise its great and you're getting the desired result too.