Creating custom dialog in Android

This blog shows you an example on how to create custom dialog. For more information on creating different kind of dialogs, please visit http://developer.android.com/guide/topics/ui/dialogs.html
1. Create layout for the dialog

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:orientation="vertical" 
    android:padding="10sp">
    <EditText android:text="" 
        android:id="@+id/categoryEditText" 
        android:layout_height="wrap_content" 
        android:layout_width="fill_parent" 
        android:singleLine="true">
    </EditText>    
</LinearLayout>

2. Override onCreateDialog in the Activity

@Override
protected Dialog onCreateDialog(int id) {
    switch (id) {
        case CATEGORY_DETAIL:
            LayoutInflater li = LayoutInflater.from(this);
            View categoryDetailView = li.inflate(R.layout.category_detail, null);
            
            AlertDialog.Builder categoryDetailBuilder = new AlertDialog.Builder(this);
            categoryDetailBuilder.setTitle("Edit Category");
            categoryDetailBuilder.setView(categoryDetailView);
            AlertDialog categoryDetail = categoryDetailBuilder.create();
            
            categoryDetail.setButton("OK", new OnClickListener(){
            
            @Override
            public void onClick(DialogInterface dialog, int which) {
                AlertDialog categoryDetail = (AlertDialog)dialog;
                EditText et = (EditText)categoryDetail.findViewById(R.id.categoryEditText);
                if (categories.get(selectedIndex)!=null){
                    //... some code
                }               
            });
            
            categoryDetail.setButton2("Cancel", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {
                return;
            }}); 
            
            return categoryDetail;
        default:
            break;
    }
    return null;
}

3. Override onPrepareDialog to dynamically set default value before the dialog is open

@Override
protected void onPrepareDialog(int id, Dialog dialog) {
    switch (id) {
        case CATEGORY_DETAIL:
            AlertDialog categoryDetail = (AlertDialog)dialog;
            EditText et = (EditText)categoryDetail.findViewById(R.id.categoryEditText);
            et.setText(defaultValue);
            break;
        default:
            break;
    }
}

4. Call showDialog to display the dialog

static final private int CATEGORY_DETAIL = 1;
//... some code
showDialog(CATEGORY_DETAIL);