在Android中动态添加行

Question

我已在单独的应用程序（测试应用程序）中编写此代码，＆amp;它工作得很好..

public class MainActivity extends Activity {

    String companies[] = {"Google","iPhone","Nokia","Samsung",
                          "Google","Windows","iPhone","Nokia","Samsung",
                          "Google","Windows","iPhone","Nokia","Samsung","waseela"};
    String os[]       =  {"Android","iOS","Bada",
                          "Android","Mango","iOS","Symbian","Bada",
                          "Android","Mango","iOS","Symbian","Bada","wwwwwwww","wx"};

    TableLayout tl;
    TableRow tr;
    TextView companyTV,valueTV;
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
       tl = (TableLayout) findViewById(R.id.maintable);
       addHeaders();
       addData();
   }
   /** This function add the headers to the table **/
   public void addHeaders(){

        /** Create a TableRow dynamically **/
       tr = new TableRow(this);
       tr.setLayoutParams(new LayoutParams(
               LayoutParams.FILL_PARENT,
               LayoutParams.WRAP_CONTENT));

       /** Creating a TextView to add to the row **/
       TextView companyTV = new TextView(this);
       companyTV.setText("Companies");
       companyTV.setTextColor(Color.GRAY);
       companyTV.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
       companyTV.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
       companyTV.setPadding(5, 5, 5, 0);
       tr.addView(companyTV);  // Adding textView to tablerow.

       /** Creating another textview **/
       TextView valueTV = new TextView(this);
       valueTV.setText("Operating Systems");
       valueTV.setTextColor(Color.GRAY);
       valueTV.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
       valueTV.setPadding(5, 5, 5, 0);
       valueTV.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
       tr.addView(valueTV); // Adding textView to tablerow.

       // Add the TableRow to the TableLayout
       tl.addView(tr, new TableLayout.LayoutParams(
               LayoutParams.FILL_PARENT,
               LayoutParams.WRAP_CONTENT));

       // we are adding two textviews for the divider because we have two columns
       tr = new TableRow(this);
       tr.setLayoutParams(new LayoutParams(
               LayoutParams.FILL_PARENT,
               LayoutParams.WRAP_CONTENT));

       /** Creating another textview **/
       TextView divider = new TextView(this);
       divider.setText("-----------------");
       //divider.setTextColor(Color.<span class="IL_AD" id="IL_AD11">GREEN</span>);
       divider.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
       divider.setPadding(5, 0, 0, 0);
       divider.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
       tr.addView(divider); // Adding textView to tablerow.

       TextView divider2 = new TextView(this);
       divider2.setText("-------------------------");
       divider2.setTextColor(Color.GREEN);
       divider2.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
       divider2.setPadding(5, 0, 0, 0);
       divider2.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
       tr.addView(divider2); // Adding textView to tablerow.

       // Add the TableRow to the TableLayout
       tl.addView(tr, new TableLayout.LayoutParams(
               LayoutParams.FILL_PARENT,
               LayoutParams.WRAP_CONTENT));
   }
   /** This function add the data to the table **/
   public void addData(){

       for (int i = 0; i < companies.length; i++)
       {
           /** Create a TableRow dynamically **/
           tr = new TableRow(this);
           tr.setLayoutParams(new LayoutParams(
                   LayoutParams.FILL_PARENT,
                   LayoutParams.WRAP_CONTENT));

           /** Creating a TextView to add to the row **/
           companyTV = new TextView(this);
           companyTV.setText(companies[i]);
           companyTV.setTextColor(Color.RED);
           companyTV.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
           companyTV.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
           companyTV.setPadding(5, 5, 5, 5);
           tr.addView(companyTV);  // Adding textView to tablerow.

           /** Creating another textview **/
           valueTV = new TextView(this);
           valueTV.setText(os[i]);
           valueTV.setTextColor(Color.GREEN);
           valueTV.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
           valueTV.setPadding(5, 5, 5, 5);
           valueTV.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
           tr.addView(valueTV); // Adding textView to tablerow.

           // Add the TableRow to the TableLayout
           tl.addView(tr, new TableLayout.LayoutParams(
                   LayoutParams.FILL_PARENT,
                   LayoutParams.WRAP_CONTENT));
       }
   }
}

xml文件，其中包含一个包含tablelayout的ScrollView。

问题是，当我将该代码放在我正在处理的主项目中时，它什么也没显示。我已将xml布局嵌入到主项目布局中，我没有收到任何错误但没有显示任何内容。

我怎样才能使这个工作？