Unchecked call to add(E) as a member of raw type java.util.List

SeekBar setOnSeekBarChangeListener Example. Change TextView font size by SeekBar Example.

        TextView mTextView01 = (TextView)findViewById(R.id.textView01);

        SeekBar  mSeekBarTexSize = (SeekBar)findViewById(R.id.seekBarTextSize);
        mSeekBarTexSize.setMax(100);
        mSeekBarTexSize.setProgress(25);

        mSeekBarTexSize.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            public void onProgressChanged(SeekBar seekBar, int progress,
                    boolean fromUser) {
            	mTextView01.setTextSize((float)progress);
            }

            public void onStartTrackingTouch(SeekBar seekBar) {}
            public void onStopTrackingTouch(SeekBar seekBar) {}
        });

If you change android:versionCode="224" and android:versionName="2.2.4" in AndroidManifest.xml you have to change this in build.gradle file too.
Click on build.gradle in package explorer tree change your new version name and code:

  defaultConfig {
        applicationId "cz.okhelp.pocasiwidget"
        minSdkVersion 11
        targetSdkVersion 23
        versionCode 224
        versionName "2.2.4"
    }

Try this solutions:
1.) Save xml file
2.) Close tab with xml file
3.) Reopen xml file

1.) Open from menu Window->Android SDK Manager
2.) Select available updates (Tools, SDK etc.)
3.) Install updates

1.) Open from menu Help->Check for Updates
2.) Install available plugins what You need
3.) Restart Eclipse

Try this code with CursorLoader:

Uri uri = getIntent().getData();

// DEPRECATED
Cursor cursor = managedQuery(uri, null, null, null, null);

// WORKING - loadInBackground() preventing freezing of app
 Cursor cursor  = new CursorLoader(getApplicationContext(),uri, null, null, null, null).loadInBackground();
        

Spinner in Android application is equivalent of ComboBox in WinApi.
Spinner get selected item to string example.
Spinner get selected item position to int example.

Main activity class MainComboBox.java

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

        Spinner spinner = (Spinner) findViewById(R.id.spinner);
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(
                this, R.array.countries_array, android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(new MyOnItemSelectedListener());

        Button myButton =(Button)findViewById(R.id.button1);
        myButton.setOnClickListener(new Button.OnClickListener() {
            public void onClick(View v) {
            	
            Spinner sp =	(Spinner)findViewById(R.id.spinner);
            String spinnerString = null;
            spinnerString = sp.getSelectedItem().toString();
            int nPos = sp.getSelectedItemPosition();
            
             
                Toast.makeText(getApplicationContext(), "getSelectedItem=" + spinnerString,
                    Toast.LENGTH_LONG).show();
                Toast.makeText(getApplicationContext(), "getSelectedItemPosition=" + nPos,
                		Toast.LENGTH_LONG).show();
            }
        });
    }
}

File MyOnItemSelectedListener.java

public  class MyOnItemSelectedListener implements OnItemSelectedListener {

    public void onItemSelected(AdapterView<?> parent,
        View view, int pos, long id) {
      Toast.makeText(parent.getContext(), "Item is " +
          parent.getItemAtPosition(pos).toString(), Toast.LENGTH_LONG).show();
    }

    public void onNothingSelected(AdapterView parent) {
      // Do nothing.
    }
}

strings.xml

<resources>
    <string name="hello">Hello World, MainComboBox!</string>
    <string name="app_name">ComboBox</string>
    <string name="prompt">Choose a country</string>
    <string-array name="countries_array">
        <item>China</item>
        <item>India</item>
        <item>USA</item>
        <item>Indonesia</item>
        <item>Brazil</item>
        <item>Pakistan</item>
        <item>Nigeria</item>
        <item>Bangladesh</item>
        <item>Russia</item>
    </string-array>    
</resources>

main.xml

<LinearLayout xmlns:android="//schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:padding="10dip"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dip"
        android:text="@string/prompt"
    />
    <Spinner 
        android:id="@+id/spinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:prompt="@string/prompt"
    />
    <Button android:text="Button" android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button>

</LinearLayout>