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at java.util.Arrays$ArrayList.get(Arrays.java:75)

Problem in Android application:

E/AndroidRuntime(416): FATAL EXCEPTION: main
E/AndroidRuntime(416): java.lang.IndexOutOfBoundsException
E/AndroidRuntime(416): 	at java.util.Arrays$ArrayList.get(Arrays.java:75)
E/AndroidRuntime(416): 	at android.widget.ArrayAdapter.getItem(ArrayAdapter.java:298)
E/AndroidRuntime(416): 	at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:351)
E/AndroidRuntime(416): 	at android.widget.ArrayAdapter.getView(ArrayAdapter.java:323)
E/AndroidRuntime(416): 	at android.widget.Spinner.makeAndAddView(Spinner.java:192)
E/AndroidRuntime(416): 	at android.widget.Spinner.layout(Spinner.java:151)
E/AndroidRuntime(416): 	at android.widget.Spinner.onLayout(Spinner.java:115)


Solution: check code for set and get selection

// Spinner _spin1 contain only  49 items 
// you can set max 48 ( range 0 - 48)
// 50 is IndexOutOfBoundsException
_spin1.setSelection(50);

396LW NO topic_id




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256

Two boolean as one parameter value in function Java | two-boolean-as-one-parameter-value-in-function-java



boolean fc(boolean b) {
	return b;
}// end fc
		boolean bA = true;
		boolean bB = true;
		boolean bC = bA || bB; // true

		bA = true;
		bB = false;
		bC = bA || bB; // true

		bA = false;
		bB = true;
		bC = bA || bB; // true

		bA = false;
		bB = false;
		bC = bA || bB; // false
		
			if(!fc(bB||bA))
			System.out.println("false"); // false
                        else 
			System.out.println("true"); 


357

Resource Entry already defined | resource-entry-already-defined


Check if in drawable folder have two picture with same name and delete one.
For example:

image_1.jpg
image_1.png


Check the module build folder in Android Studio for two files with same names.

C:\Users\myFolder\AndroidStudioProjects\Project\yourModule\build\intermediates\res\merged\debug\drawable\
145

Compressing converting a bitmap to PNG format Android example | compressing-converting-a-bitmap-to-png-format-android-example



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

	private static Bitmap codec(Bitmap src, Bitmap.CompressFormat format,
			int quality) {
		ByteArrayOutputStream os = new ByteArrayOutputStream();
		src.compress(format, quality, os);

		byte[] array = os.toByteArray();
		return BitmapFactory.decodeByteArray(array, 0, array.length);
	}

	private static class SampleView extends View {

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

		}
		@Override
		protected void onDraw(Canvas canvas) {
			Paint paint = new Paint();
			
			canvas.drawColor(Color.YELLOW);
            
        
			Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.flower_blue);
             
			Bitmap bPNGcompress = codec(bmp, Bitmap.CompressFormat.PNG, 0);

		   int h = bmp.getHeight();
           
           canvas.drawBitmap(bmp, 10,10, paint);
           canvas.drawBitmap(bPNGcompress, 10,10 + h + 10, paint);
           
		}

	}
}

132

Draw circle Android basic example | draw-circle-android-basic-example


Canvas, drawCircle(), Paint, onDraw(), setStrokeWidth(), 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(4.5f);
			// opacity
			//p.setAlpha(0x80); //
			canvas.drawCircle(50, 50, 30, p);
		}

	}
}

35

Android startup tutorial for developers video | android-startup-tutorial-for-developers-video


How install Android emulator on PC
//developer.android.com/sdk/installing.html

Download links:
Java Development Kit JDK download
Eclipse download
Android SDK download