How to create icon for Android apps

Wiktionary - SDK samples Android

    protected void showAbout() {
        // Inflate the about message contents
        View messageView = getLayoutInflater().inflate(R.layout.about, null, false);

        // When linking text, force to always use default color. This works
        // around a pressed color state bug.
        TextView textView = (TextView) messageView.findViewById(R.id.about_credits);
        int defaultColor = textView.getTextColors().getDefaultColor();
        textView.setTextColor(defaultColor);

        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setIcon(R.drawable.app_icon);
        builder.setTitle(R.string.app_name);
        builder.setView(messageView);
        builder.create();
        builder.show();
    }

about.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2009 The Android Open Source Project
          //www.apache.org/licenses/LICENSE-2.0
-->

<LinearLayout xmlns:android="//schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="20dip">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="16sp"
        android:text="@string/app_descrip"
        android:textColor="?android:attr/textColorPrimaryInverse" />

    <TextView
        android:id="@+id/about_credits"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingTop="20dip"
        android:textSize="16sp"
        android:text="@string/app_credits"
        android:autoLink="web"
        android:textColor="?android:attr/textColorPrimaryInverse" />

</LinearLayout>

Check your xml files in Eclipse Graphical Editor and fix problems.



Check project setup, right click on project, select properties, Java build path and
select correct Android version etc.


Right click on project, Android Tools, Fix Project Properties

Menu Eclipse select Project ->Clean.

Canvas, drawLine(), setStrokeWidth(), Paint, setAntiAlias(boolean), onDraw()

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.YELLOW);
			Paint p = new Paint();
			// smooths
			p.setAntiAlias(true);
			p.setColor(Color.RED);
			p.setStrokeWidth(4.5f);
			// opacity
			p.setAlpha(0x80); //
			// drawLine (float startX, float startY, float stopX, float stopY,
			// Paint paint)
			canvas.drawLine(0, 0, 40, 40, p);
			canvas.drawLine(40, 0, 0, 40, p);

		}

	}
}

Samsung Galaxy S II cena od 10 000 KCZ Kč (únor.2012).
Asi nejlepší smartphone (cena : vlastnosti) telefon s Androidem roku 2011.
Samsung Galaxy S II (GT-I9100) je chytrý telefon běžící na operačním systému Android, který byl představen firmou Samsung 13. února 2011.
Samsung Galaxy S II je (22.února2012) nejpoužívanějším chytrým telefonem u programu Sky Map viz tabulka.

Proč je Samsung Galaxy S2 tak oblíben?
Galaxy S II má 1.2 GHz dual-core "Exynos" procesor, 1 GB RAM, 10,8 cm WVGA AMOLED Super Plus displej a fotoaparát s 8 miliony pixelů i s bleskem a plné vysoké rozlišení 1080p nahrávání videa. Je to jedno z prvních zařízení, které nabízí mobilní high-definition Link (MHL), který umožňuje až 1080p nekomprimovaného obrazového výstupu HDMI. USB On-The-Go (USB OTG) je podporováno.

Vyměnitelná baterie na Galaxy S II vydrží až deset hodin při intenzivním používání, nebo dva dny lehčí provoz. Podle společnosti Samsung, Galaxy S II je schopen poskytovat 9 hodin hovoru v 3G a 18,3 hodin na 2G síti.

Samsung Galaxy S2 photo pic image

Zdroj obrázku: wikipedia

Call findViewById from onCreateView

public class MainActivity extends ActionBarActivity {

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

		if (savedInstanceState == null) {
			getSupportFragmentManager().beginTransaction()
					.add(R.id.containerMoje, new PlaceholderFragment()).commit();
		}
		
	}


	/**
	 * A placeholder fragment containing a simple view.
	 */
	public static class PlaceholderFragment extends Fragment {
		public PlaceholderFragment() {
		}

		@Override
		public View onCreateView(LayoutInflater inflater, ViewGroup container,
				Bundle savedInstanceState) {
			View rootView = inflater.inflate(R.layout.fragment_main, container,
					false);
			if (container == null) {
		        return null;
		    }


			 TextView mText;
			mText = (TextView)rootView.findViewById(R.id.idText);
			mText.setText("Hello from fragment_main");

			return rootView;
		}
	}
}

res\layout
activity_main.xml

<FrameLayout xmlns:android="//schemas.android.com/apk/res/android"
    xmlns:tools="//schemas.android.com/tools"
    android:id="@+id/containerMoje"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="cz.okhelp.autoskola.MainActivity"
    tools:ignore="MergeRootFrame" />

fragment_main.xml

<RelativeLayout xmlns:android="//schemas.android.com/apk/res/android"
    xmlns:tools="//schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="cz.okhelp.autoskola.MainActivity$PlaceholderFragment" >

    <TextView
        android:id="@+id/idText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

</RelativeLayout>