Problemas com tabActivity[Android]

<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/tabhost"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    

//O PRIMEIRO PROBLEMA ESTA AQUI ESSA IMAGEM NAO APARECE

    <LinearLayout android:layout_width="fill_parent"
        android:layout_height="fill_parent">
        <ImageView
	            android:id="@+id/imgTitulo"
	            android:layout_width="wrap_content"
	            android:layout_height="wrap_content"
	            android:src="@drawable/logo_top"/>
    </LinearLayout>
    
    <LinearLayout 
        android:orientation="vertical"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent">
    
    <TabWidget android:id="@android:id/tabs"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:background="#0000FF"
        
        
        />
    <FrameLayout 
        android:id="@android:id/tabcontent"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:padding="5dp"/>
    </LinearLayout>
</TabHost>

public class Tabs extends ActivityGroup {
	static TabHost tabHost;
	static int tab=-1;
	public static final int DATA = 0;
	public static final int VEICULO = 1;
	public static final int TIPO = 2;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		setContentView(R.layout.tabs);
		
		Resources res = getResources();
		tabHost = (TabHost)findViewById(R.id.tabhost);
		tabHost.setup(this.getLocalActivityManager());
		TabHost.TabSpec spec;
		Intent intent;
		
		//Adiciona a tab #1
		intent = new Intent().setClass(this, ListarMaterias.class);
		spec = tabHost.newTabSpec("0").setIndicator("Matérias",res.getDrawable(R.drawable.tab_materia)).setContent(intent);		
		tabHost.addTab(spec);
		
		//Adiciona a tab #2
		intent = new Intent().setClass(this,MeteriaSwitcher.class);
		spec = tabHost.newTabSpec("1").setIndicator("Mais Lidas",res.getDrawable(R.drawable.ico_capas)).setContent(intent);
		tabHost.addTab(spec);
		
		tabHost.setCurrentTab(0);
	}
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// TODO Auto-generated method stub
		super.onCreateOptionsMenu(menu);
		//Adiciona três opções no menu
		MenuItem item = menu.add(0,DATA,0,"Data");
		item.setIcon(R.drawable.ic_launcher);
		item = menu.add(0,VEICULO,0,"Veículo");
		item.setIcon(R.drawable.ic_launcher);
		item = menu.add(0,TIPO,0,"Tipo");
		item.setIcon(R.drawable.ic_launcher);
		return true;
	}
	@Override
	public boolean onMenuItemSelected(int featureId, MenuItem item) {
		// TODO Auto-generated method stub
		switch (item.getItemId()) {
		case DATA:
			String titulo = item.getTitle().toString();
			Toast.makeText(Tabs.this, "Item: " + titulo, Toast.LENGTH_SHORT).show();
			return true;
		case VEICULO:
			titulo = item.getTitle().toString();
			Toast.makeText(Tabs.this, "Item: " + titulo, Toast.LENGTH_SHORT).show();
			return true;
		case TIPO:
			titulo = item.getTitle().toString();
			Toast.makeText(Tabs.this, "Item: " + titulo, Toast.LENGTH_SHORT).show();
			return true;
		default:
			break;
		}
		return false;
	}
}