Android AlertDialog with rounded corners

You can do it using the following code:

CustomDialog.java:

public class MainActivity extends Activity{

    private static final int ALERT_DIALOG = 1;

    @Override
    public void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.main );

        ( (Button) findViewById( R.id.button1 ) )
            .setOnClickListener( new OnClickListener()
                {
                    public void onClick( View v )
                    {
                        showDialog( ALERT_DIALOG );
                    }
                }
            );
    }

    @Override
    protected Dialog onCreateDialog( int id ){
        Dialog dialog = null;
        if ( id == ALERT_DIALOG )
        {
            ContextThemeWrapper ctw = new ContextThemeWrapper( this, R.style.MyTheme );
            AlertDialog.Builder builder = new AlertDialog.Builder( ctw );
            builder.setMessage( "Hello World" )
                .setTitle( "Alert Dialog" )
                .setIcon( android.R.drawable.ic_dialog_alert )
                .setCancelable( false )
                .setPositiveButton( "Close", new DialogInterface.OnClickListener()
                    {
                        public void onClick( DialogInterface dialog, int which )
                           {
                                dialog.dismiss();
                           }
                        } 
                    );
            dialog = builder.create();
        }
        if ( dialog == null )
        {
            dialog = super.onCreateDialog( id );
        }
        return dialog;
     }
 }

dialog_title.xml

<?xml version="1.0" encoding="utf-8"?>
<inset xmlns:android="http://schemas.android.com/apk/res/android" android:insetBottom="-1dp">
    <shape android:shape="rectangle">
        <solid android:color="#000000" />
        <corners android:topLeftRadius="20dp" android:topRightRadius="20dp" />
        <stroke android:color="#7F7F7F" android:width="1dp" />
    </shape>
</inset>

dialog_footer.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#7F7F7F" />
    <corners android:bottomLeftRadius="20dp" android:bottomRightRadius="20dp" />
    <stroke android:color="#7F7F7F" android:width="1dp" />
</shape>

Just change the radius amount in:

dialog_title.xml

and

dialog_footer.xml

and that’ll generate the following output:

hope this will help you.

---

UPDATE:
I’m not an expert but this is what I found. It may be right or wrong.
After many attempts I ended up with the following:

1- ContextThemeWrapper is not applicable for API 14, it works fine on Gingerbread and older versions but with API > 10 it doesn’t work.

2- to overcome the above issue and make it work on API > 10 as requested, I replace this line:

ContextThemeWrapper ctw = new ContextThemeWrapper( this, R.style.MyTheme );
AlertDialog.Builder builder= new AlertDialog.Builder( ctw );

with this:

AlertDialog.Builder builder= new AlertDialog.Builder( this,R.style.MyTheme );

but you need to change:

android:minSdkVersion="8"  

to

android:minSdkVersion="11" 

the result will be as shown in the following image on ICS (API 14):

This image is from a Samsung Galaxy S3 running ICS.

Note: modified project initiated with API 14 SO manifest sdk will be:

<uses-sdk
  android:minSdkVersion="11"
  android:targetSdkVersion="15" />

---

FINAL WORD:
As my little knowledge in Android development (I’m not an expert),

1- custom alert dialog runs smoothly in API < 10 but not > 10 with the same Java code,

if we want it to run in ICS with the same effect as appeared in API < 10, we need to modify the code, so it will run on ICS but will not run in any version down API 11.

2- even the result in ICS is not satisfactory, the round corner applies only to the title but not the footer.

---

SECOND UPDATE:
FINALLY I get all corners round,

JUST apply padding to dialog_footer.xml as follows:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
    <solid android:color="#7F7F7F" />
    <corners android:bottomLeftRadius="20dp" android:bottomRightRadius="20dp" />
    <stroke android:color="#7F7F7F" android:width="1dp" />
    <padding android:left="10dp" android:top="10dp" android:right="10dp"
android:bottom="10dp" /> 
</shape>

Output image:

This image is from a Samsung Galaxy S3 running ICS.