Titlebar title bar change text setTile Android example

drawArc(), Canvas, Paint, setStyle()

public class MainActivity extends Activity {
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {

		// CONSTRUCTOR
		public SampleView(Context context) {
			super(context);
			setFocusable(true);

		}

		@Override
		protected void onDraw(Canvas canvas) {

			canvas.drawColor(Color.CYAN);
			Paint p = new Paint();
			// smooths
			p.setAntiAlias(true);
			p.setColor(Color.RED);
			p.setStyle(Paint.Style.STROKE); 
			p.setStrokeWidth(5);
			// opacity
			//p.setAlpha(0x80); //
 
			RectF rectF = new RectF(50, 20, 100, 80);
			canvas.drawOval(rectF, p);
			p.setColor(Color.BLACK);
			canvas.drawArc (rectF, 90, 45, true, p);
		}

	}
}

FrameLayou, fragment have to unique id android:id="@+id/your_id_unique"

<FrameLayout xmlns:android="//schemas.android.com/apk/res/android"
    xmlns:tools="//schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <fragment
        android:id="@+id/your_id_unique"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        class="cz.okhelp.notepad.AddNoteFragment"
        tools:layout="@layout/add_note" />

</FrameLayout>

How set rounded corners and own styles ActivityMy.java

Button btn.setBackgroundResource(R.drawable.back_button_answer);

\res\drawable\back_button_answer.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="//schemas.android.com/apk/res/android" android:shape="rectangle" >
   <corners android:radius="10dip" />
   <!-- background -->
   
   <gradient
                android:startColor="#D6D7D6"
                android:centerColor="#E2E2E2"
                android:centerY="0.75"
                android:endColor="#D6D7D6"
                android:angle="270"
        />
   
   <stroke android:width="2dip" android:color="#fff"/>
</shape>

Very very quick start of Android Emulator from Eclipse.

1. Go to Eclipse s menu Window -> Android SDK and AVD Manager


2. Select Virtual devices


3. Select check box Snapshot: Enabled


4. Press Edit AVD button.

If will closed Android Emulator all data will saved on disk.
If will reopen Android Emulator, configuration and data will read from disk.


[caption id="attachment_768" align="alignleft" width="300" caption="android-emulator-enable-quick-start"][/caption]

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>