Question

I am writing my first APK and I need some help. I find myself using a lot of similar code to find preference from a preference XML.

Here is a code snippet:

    final Preference backupPref = findPreference("backuptw");
    backupPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
        public boolean onPreferenceClick(Preference preference) {
            if(preference == backupPref)doBackup();
            return true;
        }
    });
    final Preference restorePref = findPreference("restoretw");
    restorePref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
        public boolean onPreferenceClick(Preference preference) {
            if(preference == restorePref)doRestore();
            return true;
        }
    });
    final Preference tw160Pref = findPreference("tw160");
    tw160Pref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
        public boolean onPreferenceClick(Preference preference) {
            if(preference == tw160Pref)doTW("160");
            return true;
        }
    });
    final Preference tw192Pref = findPreference("tw192");
    tw192Pref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
        public boolean onPreferenceClick(Preference preference) {
            if(preference == tw192Pref)doTW("192");
            return true;
        }
    });
    final Preference tw240Pref = findPreference("tw240");
    tw240Pref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
        public boolean onPreferenceClick(Preference preference) {
            if(preference == tw240Pref)doTW("240");
            return true;
        }
    });
    final Preference restartPref = findPreference("restart");
    restartPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
        public boolean onPreferenceClick(Preference preference) {
            if(preference == restartPref)doRestart();
            return true;
        }
    });
    final Preference sortPref = findPreference("sort");
    sortPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
        public boolean onPreferenceClick(Preference preference) {
            if(preference == sortPref)doSort();
            return true;
        }
    });

I am using findPreference a lot of times, which I do not like at all. Can anyone suggest something better?

Answer 1

You can make a HashMap for all your preferences where keys will be names of preferences and values some integer indexes which you will add. E.g.

final int INDEX_BACKUPTW = 0;

HashMap<String, Integer> mPrefMap = new HashMap<String, Integer>();

mPrefMap.put("backuptw", INDEX_BACKUPTW)

And so on…
Then just make only one onClickListener like this:

OnPreferenceClickListener(){
    public boolean onPreferenceClick(Preference preference) {
        if (preference.hasKey()) {
            int index = mPrefMap.get(preference.getKey());
            switch (index)
            {
                case INDEX_BACKUPTW:
                   doBackup();
                   break;
                case INDEX_SOME_OTHER_INDEX_I_HAVE:
                   doWhatever();
                   break;
                default:
                   Log.e(TAG, "Achtung!");
            }
        }
        return true;
    }
}

Assign this listener to all your preferences and have fun. In this case your code will not look like it does now.