How to Scroll large image in ImageView Android Example

Spinner, ArrayAdapter, setOnItemSelectedListener, onItemSelected, setDropDownViewResource

MainClass.java

public class Vypocet extends Activity {
 Spinner   hSpinnerMetry;
// .......
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

	       hSpinnerMetry = (Spinner) findViewById(R.id.idSpinnerMetry);
	        ArrayAdapter<CharSequence> adapterMetry = ArrayAdapter.createFromResource(
	        		this, R.array.metry_array, android.R.layout.simple_spinner_item);
	        adapterMetry.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
	        hSpinnerMetry.setAdapter(adapterMetry);
			
	           hSpinnerMetry.setOnItemSelectedListener(
	                    new OnItemSelectedListener() {
	                        public void onItemSelected(
	                                AdapterView<?> parent, View view, int position, long id) {
	                        int nPos = position;
	                        }

	                        public void onNothingSelected(AdapterView<?> parent) {
	                        
	                        }
	                    });	        

      }
}

strings.xml

<string-array name="metry_array">
<item>m</item>
<item>dm</item>
<item>cm</item>
<item>mm</item>
</string-array>

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);
		}

	}
}

Landscape - portrait orientation change:

boolean mbOrientationLandscape = true;
if(mbOrientationLandscape ){
	setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
	mbOrientationLandscape =false;
}else{
	setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
	mbOrientationLandscape =true;
}

public class ApokusActivity 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) {
			Paint paint = new Paint();
			
			canvas.drawColor(Color.GREEN);
            
            Bitmap b = Bitmap.createBitmap(200, 200, Bitmap.Config.ALPHA_8);
             paint.setColor(Color.BLUE);
            
            Shader mShader = new LinearGradient(0, 0, 100, 70, new int[] {
                    Color.RED, Color.GREEN, Color.BLUE },
                    null, Shader.TileMode.MIRROR);  // CLAMP MIRROR REPEAT
            Canvas c = new Canvas(b);
            paint.setShader(mShader);
            //c.drawCircle(60, 60, 30, paint);
            c.drawRect(0, 0, 200, 200, paint);
            canvas.drawBitmap(b, 10,10, paint);
		}

	}
}

Problemi is in e.getMessage() what can return null and Log.e (String tag, String msg) will throws an new exception !!!!
Problem and solution:

      	try {
      		int [] i = {1};
      		int z = i[5];
      	} catch (ArrayIndexOutOfBoundsException e) {
      		String s = e.toString(); // s == java.lang.ArrayIndexOutOfBoundsException
                // try to testing String s for null value
      		if(s != null)
      		 Log.e("bla", s);
      		else 
      		 Log.e("bla", "My error text 1");
      		
      		String s2 = e.getMessage(); // s2 == null !!!!!!!
                // you need to testing String s2 for null value , or you get FATAL EXCEPTION: main
                // and application will be crashed
       		String s2 = e.getMessage(); // s2 == null !!!!!!!
      		if(s2 != null)
      		 Log.e("bla2", e.getMessage());
      		else 
      		 Log.e("bla2", "My error text 2");
     		
                // this is OK
      		e.printStackTrace();
      	}

LogCat:

E/bla(855): java.lang.ArrayIndexOutOfBoundsException

 E/bla2(855): My error text 2

 W/System.err(855): java.lang.ArrayIndexOutOfBoundsException
 W/System.err(855): 	at cz.okhelp.motion._MotionActivity.onTouchEvent(_MotionActivity.java:54)
 W/System.err(855): 	at android.app.Activity.dispatchTouchEvent(Activity.java:2099)
 W/System.err(855): 	at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1675)
 W/System.err(855): 	at android.view.ViewRoot.deliverPointerEvent(ViewRoot.java:2194)
 W/System.err(855): 	at android.view.ViewRoot.handleMessage(ViewRoot.java:1878)
 W/System.err(855): 	at android.os.Handler.dispatchMessage(Handler.java:99)
 W/System.err(855): 	at android.os.Looper.loop(Looper.java:123)
 W/System.err(855): 	at android.app.ActivityThread.main(ActivityThread.java:3683)
 W/System.err(855): 	at java.lang.reflect.Method.invokeNative(Native Method)
 W/System.err(855): 	at java.lang.reflect.Method.invoke(Method.java:507)
 W/System.err(855): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
 W/System.err(855): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
 W/System.err(855): 	at dalvik.system.NativeStart.main(Native Method)

Or you can using this code:

      	try {
      		int [] i = {1};
      		int z = i[5];
      	} catch (Exception e) {
      		
      		
      		StringBuilder sb = new  StringBuilder().append(e.getClass().getSimpleName()); 
          if  (e.getMessage() != null) { 
              sb.append("

"); 
              sb.append(e.getMessage()); 
          } 
          Log.e("err", sb.toString()); // E/err(336): ArrayIndexOutOfBoundsException

          // this code write out all message
          Log.e("myError", "methodName", e);
       }
// E/myError(371): methodName
// E/myError(371): java.lang.ArrayIndexOutOfBoundsException
// E/myError(371): 	at cz.okhelp.motion._MotionActivity.onTouchEvent(_MotionActivity.java:54)
// E/myError(371): 	at android.app.Activity.dispatchTouchEvent(Activity.java:2099)
// E/myError(371): 	at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1675)
// E/myError(371): 	at android.view.ViewRoot.deliverPointerEvent(ViewRoot.java:2194)
// E/myError(371): 	at android.view.ViewRoot.handleMessage(ViewRoot.java:1878)
// E/myError(371): 	at android.os.Handler.dispatchMessage(Handler.java:99)
// E/myError(371): 	at android.os.Looper.loop(Looper.java:123)
// E/myError(371): 	at android.app.ActivityThread.main(ActivityThread.java:3683)
// E/myError(371): 	at java.lang.reflect.Method.invokeNative(Native Method)
// E/myError(371): 	at java.lang.reflect.Method.invoke(Method.java:507)
// E/myError(371): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
// E/myError(371): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
// E/myError(371): 	at dalvik.system.NativeStart.main(Native Method)