AutoCompleteTextView doesn't show suggestions in Android 2.3.5

Question

I'm using a special autocompletetextview for suggestions of thousands of streets. Due to this huge element list, I have to clear and populate the Adapter on the fly depending on the first input letter. For example, when the user enters "b", the Adapter is being populated with all streets beginning with "b". This works in all Android versions. Today one user told me that there are problems in Android 2.3.5, Samsung Galaxy Ace.

When he begins to enter letters, there is no dropdown with suggestions. When he enters "b", it only suggest streets which consist of two names while the second name begins with "b". For example: the proposals he get for "b" is "Am Bahnhof" or "Alte Bahnstraße". There seems to be a pattern, but I can't explain how this happens and I can't reproduce this, neither in any emulator nor on a real device (moreover there is no 2.3.5 emulator).

Below is the code. Just for information: I have to clear in beforeTextChange, otherwise the application would crash when I delete the input in the field very quickly. Obviously it can't exchage the lists fast enough. And I need the variable alreadyAdded, otherwise it would add the list twice when I delete the input down to the first letter.

What is really strange: I've never changed this part since the first implementation and the user told me it worked at the first version. But suddendly it doesn't work anymore. Is it possible that the compiled code is somehow corrupt? Any ideas?

I would also accept a solution when somebody could tell me how to reproduce this.

Invocation:

autoCompleteTextView.addTextChangedListener(new StreetTextWatcher(adapter));

StreetArrayAdapter:

public class StreetArrayAdapter extends ArrayAdapter<String> {

    public StreetArrayAdapter(Context context, int textViewResourceId) {
        super(context, textViewResourceId);
    }

    public void addAll(String[] streets) {
        for (String street : streets) {
            add(street);
        }
    }
}

StreetTextWatcher:

public class StreetTextWatcher implements TextWatcher {

    private final StreetArrayAdapter adapter;
    private boolean alreadyAdded = false;

    public StreetTextWatcher(StreetArrayAdapter adapter) {
        this.adapter = adapter;
    }

    @Override
    public void afterTextChanged(Editable s) {
        //not used
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        if (s.length() < 1)  {
            adapter.clear();

            alreadyAdded = false;
        }
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {           
        if (s.length() == 1) {
            populateAdapter(s);

            alreadyAdded = true;
        }
    }

    private void populateAdapter(CharSequence s) {  
        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("a") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_A);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("ä") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_A);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("b") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_B);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("c") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_C);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("d") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_D);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("e") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_E);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("f") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_F);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("g") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_G);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("h") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_H);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("i") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_I);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("j") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_J);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("k") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_K);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("l") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_L);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("m") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_M);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("n") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_N);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("o") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_O);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("ö") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_O);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("p") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_P);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("q") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_Q);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("r") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_R);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("s") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_S);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("t") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_T);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("u") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_U);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("ü") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_U);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("v") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_V);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("w") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_W);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("y") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_Y);
        }

        if (s.toString().toLowerCase(Locale.GERMAN).startsWith("z") && !alreadyAdded)  {
            adapter.addAll(StreetNames.STREETS_Z);
        }
    }
}

Obviously there is something different, because I can't reproduce it with 2.3.3 — Bevor, Jan 30 '13 at 09:54
@StarsSky How is it possible to set a custom keyboard? Maybe I could check this in emulator. — Bevor, Feb 13 '13 at 07:19
Just a quick optimisation... I would change the if statements inside the populateAdapter method to if/elseif/else because if s.toString already starts with "a" then obviously it cannot start with any other conditions... — chuthan20, Feb 18 '13 at 04:37
Maybe its my lack of knowledge but y do u user Locale.GERMAN.. I thought that was used for date/money etc.. in your case, I don't see the point of using Locale since user enters a street name to search... also maybe user is missing the Locale.GERMAN?? also notice that there is Locale.GERMANY... and you should read [Be wary of the default locale](http://developer.android.com/reference/java/util/Locale.html#default_locale) .. especially this line **"The best choice there is usually Locale.US – this locale is guaranteed to be available on all devices..."** <- possible German locale is missing. — chuthan20, Feb 18 '13 at 05:25
what is the "StreetNames" in the StreetTextWatcher.java class, I am unable to get that resources — Jayesh, Feb 18 '13 at 07:04
@user1518182 I didn't think anything special as I used Locale.GERMAN. But how does it behave, when there are Umlauts like äöü? Nevertheless it probably doesn't explain why it worked on the user's device at first but suddenly not. I don't think he looses the German locale. — Bevor, Feb 18 '13 at 07:33
@user1518182 I changed the locale to US. Umlauts do still work in the autocomplete dropdown, so maybe this could help. I will release this and ask the user if the error is gone. — Bevor, Feb 18 '13 at 17:50
AFAIK Locale are used so $20.00 will be converted to Euro.. Thursday -> w/e equivalent in german... or you have translation that you want to provide.. for example, a default "APP_NAME" = "Address Book".. and "APP_NAME" = "SomeThingInGerman"... when everything is setup & their locale is in German, they will see german version of the appname instead of the english version... so let's see what your user says about the fix. — chuthan20, Feb 18 '13 at 20:06

chuthan20 · Answer 1 · 2013-02-18T05:07:50.730

I made a comment about optimisation... but since I am pasting code.. I wanted to keep the format so I am pasting as the answer even though this does not answer your question.

Here is how I would've wrote the code to make it easier to change/add/maintain...

@Override
public void onTextChanged(CharSequence s, int start, int before, int count) 
{           
    if (s.length() == 1) 
    {
        if (!alreadyAdded)
        {
            alreadyAdded = true;
            populateAdapter(s);
        }
    }
}

private void populateAdapter(CharSequence s) {  
    Object arr[][] = 
    {{"a", StreetNames.STREETS_A },
     {"ä", StreetNames.STREETS_A },
     {"b", StreetNames.STREETS_B },
     {"c", StreetNames.STREETS_C },
     {"d", StreetNames.STREETS_D },
     {"e", StreetNames.STREETS_E },
     {"f", StreetNames.STREETS_F },
     {"g", StreetNames.STREETS_G },
     {"h", StreetNames.STREETS_H },
     {"i", StreetNames.STREETS_I },
     {"j", StreetNames.STREETS_J },
     {"k", StreetNames.STREETS_K },
     {"l", StreetNames.STREETS_L },
     {"m", StreetNames.STREETS_M },
     {"n", StreetNames.STREETS_N },
     {"o", StreetNames.STREETS_O },
     {"ö", StreetNames.STREETS_O },
     {"p", StreetNames.STREETS_P },
     {"q", StreetNames.STREETS_Q },
     {"r", StreetNames.STREETS_R },
     {"s", StreetNames.STREETS_S },
     {"t", StreetNames.STREETS_T },
     {"u", StreetNames.STREETS_U },
     {"ü", StreetNames.STREETS_U },
     {"v", StreetNames.STREETS_V },
     {"w", StreetNames.STREETS_W },
     {"y", StreetNames.STREETS_Y },
     {"z", StreetNames.STREETS_Z }};

    for (int i=0; i<arr.length; i++)
    {
        if (s.toString().toLowerCase(Locale.GERMAN).startsWith(arr[i][0]))  {
            adapter.addAll(arr[i][1]);
            break;
        }
    }
}

This probably won't work because it could lead to NullPointerExceptions. I dunno exactly why it happens, but it is reproducable when you delete the input very quickly. See also this posting and my answer there: http://stackoverflow.com/questions/12769552/nullpointerexception-on-dynamic-autocompletetextview/ — Bevor, Feb 18 '13 at 07:38
By the way, you never invoke clear. Every time the user adds more and more lists by searching for streets beginning with 'a' to load the list with 'a', he deletes it in the field to search for other streets beginning with 'b', the list is more and more growing and gets slower and slower. If he does this 3 or 4 times, the list already takes seconds to load. — Bevor, Feb 18 '13 at 07:52
What I meant by posting this code was.. just replace these method inside your code.. so you will have all your other methods such as beforeTextChanged which will clear the list.. Another approach is.. when the user type 'A' get all the names starts with 'A' and put it in tempList.. then when user types the next letter 'Ab' then search the tempList instead of everything again... that way.. tempList will keep on getting shorter and makes it faster to search. But when user press backspace, you have to search again from beginning. — chuthan20, Feb 18 '13 at 20:01

score -4 · Answer 2 · edited Feb 19 '13 at 12:41

use the below code for AutoComplete TextView

MainActivity.java

public class MainActivity extends Activity {

AutoCompleteTextView autoCompleteTextView;

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

    autoCompleteTextView = (AutoCompleteTextView) findViewById(R.id.AndroidBooks);

    StreetArrayAdapter adapter = new StreetArrayAdapter(MainActivity.this,
            android.R.layout.simple_gallery_item);
    autoCompleteTextView.setThreshold(1);
    autoCompleteTextView.setAdapter(adapter);
    autoCompleteTextView.addTextChangedListener(new StreetTextWatcher(
            autoCompleteTextView, adapter));

}
}

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
    <AutoCompleteTextView
        android:id="@+id/AndroidBooks"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" 
        android:inputType="text">
    </AutoCompleteTextView>
</LinearLayout>

StreetArrayAdapter.java

public class StreetArrayAdapter extends ArrayAdapter<String> {

String TAG = getClass().getSimpleName();

public StreetArrayAdapter(Context context, int textViewResourceId) {
    super(context, textViewResourceId);
}

public void addAll(String[] streets) {
    for (String street : streets) {
        Log.v(TAG, "street = " + street);
        add(street);
    }
}

@Override
public void insert(String object, int index) {
    super.insert(object, index);
}

@Override
public void notifyDataSetChanged() {
    super.notifyDataSetChanged();
}

@Override
public void setDropDownViewResource(int resource) {
    super.setDropDownViewResource(resource);
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    return super.getView(position, convertView, parent);

}


}

StreetTextWatcher.java

public class StreetTextWatcher implements TextWatcher {

private final StreetArrayAdapter adapter;
private boolean alreadyAdded = false;

String TAG = getClass().getSimpleName();
AutoCompleteTextView autoCompleteTextView;

public StreetTextWatcher(AutoCompleteTextView autoCTV,StreetArrayAdapter adapter) {
    this.adapter = adapter;
    autoCompleteTextView = autoCTV;
}

@Override
public void afterTextChanged(Editable s) {
    // not used
}

@Override
public void beforeTextChanged(CharSequence s, int start, int count,
        int after) {
    if (s.length() < 1) {
        adapter.clear();

        alreadyAdded = false;
    }
}

@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {

    Log.v(TAG, "char ---> = "+ s);
    if (s.length() == 1) {
        populateAdapter(s);

        alreadyAdded = true;
    }
}


private void populateAdapter(CharSequence s) {
    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("a")
            && !alreadyAdded) {
        Log.v(TAG, "inside A");
        adapter.addAll(StreetNames.STREETS_A);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("ä")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_A);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("b")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_B);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("c")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_C);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("d")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_D);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("e")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_E);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("f")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_F);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("g")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_G);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("h")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_H);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("i")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_I);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("j")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_J);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("k")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_K);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("l")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_L);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("m")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_M);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("n")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_N);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("o")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_O);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("ö")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_O);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("p")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_P);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("q")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_Q);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("r")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_R);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("s")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_S);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("t")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_T);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("u")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_U);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("ü")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_U);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("v")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_V);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("w")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_W);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("y")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_Y);
    }

    if (s.toString().toLowerCase(Locale.GERMAN).startsWith("z")
            && !alreadyAdded) {
        adapter.addAll(StreetNames.STREETS_Z);
    }

    autoCompleteTextView.setAdapter(adapter);
}

}

StreetNames.java

public class StreetNames {
 public static String[] STREETS_A = {"Apple", "Ant", "ana","alia"};
 public static String[] STREETS_B = {"Ball", "Baby","banana","bear"};
 public static String[] STREETS_C = {"Cat", "Coffee", "cherry", "carrot"};
 public static String[] STREETS_D = {"Doll", "Dady", "dj", "don"};
 public static String[] STREETS_E = {"Elephant", "Eye", "earing", "easy"};
 /*
  .
  .
  */
 public static String[] STREETS_Z = {"Zebra", "Zero", "zzz", "zoya"};
}

Let me know if you have any query...

AutoCompleteTextView doesn't show suggestions in Android 2.3.5

2 Answers2