AndroidHelloWorld程序

package com.example.android_hello;import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.os.Build;
import android.app.Activity;
public class MainActivity extends Activity {&＃64;Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);// if (savedInstanceState &＃61;&＃61; null) {
// getSupportFragmentManager().beginTransaction()
// .add(R.id.container, new PlaceholderFragment()).commit();
// }
}&＃64;Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);return true;}&＃64;Overridepublic boolean onOptionsItemSelected(MenuItem item) {// Handle action bar item clicks here. The action bar will// automatically handle clicks on the Home/Up button, so long// as you specify a parent activity in AndroidManifest.xml.int id &＃61; item.getItemId();if (id &＃61;&＃61; R.id.action_settings) {return true;}return super.onOptionsItemSelected(item);}/*** A placeholder fragment containing a simple view.*/
// public static class PlaceholderFragment extends Fragment {
//
// public PlaceholderFragment() {
// }
//
// &＃64;Override
// public View onCreateView(LayoutInflater inflater, ViewGroup container,
// Bundle savedInstanceState) {
// View rootView &＃61; inflater.inflate(R.layout.fragment_main, container,
// false);
// return rootView;
// }
// }

}

放入一个绝对布局和一个文本显示组件...
<RelativeLayout xmlns:android&＃61;"http://schemas.android.com/apk/res/android" android:layout_width&＃61;"fill_parent"android:layout_height&＃61;"fill_parent" ><TextView android:layout_width&＃61;"wrap_content"android:layout_height&＃61;"wrap_content"android:text&＃61;"&＃64;string/hello_world">TextView>
RelativeLayout>