Alert messagebox toast Android example code

Log.e println needs a message error.
E/AndroidRuntime(330): FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{b.paint/b.paint.MainActivity}: java.lang.NullPointerException: println needs a message

Try this code:

		// Error
                String s = null;
		Log.e("bla", s); // !!! error Log.e println needs a message error.
                // OK
		String s = null;
		Log.e("bla", s+""); // OK 

xml RelativeLayout Android example:

Eclipse graphical xml layout editor
[caption id="attachment_896" align="alignleft" width="261" caption="Relativelayout Eclipse graphical editor"][/caption]

res/layout/main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="//schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <TextView
        android:id="@+id/idLabel"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Enter word"/>
    <EditText
        android:id="@+id/idEntry"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@android:drawable/editbox_background"
        android:layout_below="@id/idLabel"/>
    <Button
        android:id="@+id/idOk"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/idEntry"
        android:layout_alignParentRight="true"
        android:layout_marginLeft="10dip"
        android:text="OK" />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toLeftOf="@id/idOk"
        android:layout_alignTop="@id/idOk"
        android:text="Cancel" />
</RelativeLayout>

/* Copyright (C) 2011 The Android Open Source Project
//www.apache.org/licenses/LICENSE-2.0
*/
public class MainActivity extends Activity {
private ImageView imageView;
private Button button1;
Drawable bitmapOrg;
private final int[] mColors =
{Color.BLUE, Color.GREEN, Color.RED, Color.LTGRAY, Color.MAGENTA, Color.CYAN,
		Color.YELLOW, Color.WHITE};
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		imageView = (ImageView)findViewById(R.id.imageView1);
		button1 = (Button)findViewById(R.id.button1);

		
		bitmapOrg = this.getResources().getDrawable(R.drawable.flower_blue);
        
        button1.setOnClickListener(new OnClickListener() {
            public void onClick(View view) {
                int mColor = (int) Math.floor(Math.random() * mColors.length);
                bitmapOrg.setColorFilter(mColors[mColor], PorterDuff.Mode.MULTIPLY);
                imageView.setImageDrawable(bitmapOrg);
                imageView.invalidate();
            }
        });	
 	}

}

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>

If You have old PC (Android in emulator with high screen resolution uses a lot of memory) or your testing phone have small screen, You can try this trick.
Rename layout folder for small device screen f.g. from layout into layout-swXXXdp and a large layout-sw600dp into layout.
Your phone with small screnn will do select xml file from renamed layout folder (for small screen).
You can to testing rotation with device en stability of fragments if an application changed orientation.
If you have old pc, you can try to make a new virtual device running on older version of Android, which uses less memory of computer.
For testing of rotation stability - application orientation changed - use on emulator Ctrl+F11, Ctrl+F12 key (Windows).

Important
Before the release of application, you have to rename layout folder to older name layout-sw600dp and layout-swXXXdp to layout.