Google Map Android

I simply want to use google api but it doesn't work I dont see a tiny mistake I guess can you help me pls ?

<application android:icon="@drawable/icon" android:label="@string/app_name">
    <activity android:name="HelloGoogleMaps"
              android:label="@string/app_name"
              android:theme="@android:style/Theme.NoTitleBar">                                    
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

</application>

import android.os.Bundle; import com.google.android.maps.MapActivity; import com.google.android.maps.MapView;

public class HelloGoogleMaps extends MapActivity {

@Override
protected boolean isRouteDisplayed() {
    // TODO Auto-generated method stub
    return false;
}

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

    MapView mapView = (MapView) findViewById(R.id.map开发者_如何学运维view);
    mapView.setBuiltInZoomControls(true);



}

}

Make sure you include inside the application tag

<uses-library android:required="true" android:name="com.google.android.maps" />

and inside the manifest tag include

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>
<uses-permission android:name="android.permission.INTERNET"></uses-permission>

also, do you include your api key in the MapView object in the main.xml file?

My MapView tag looks like:

<com.google.android.maps.MapView
             android:id="@+id/mapview"
             android:layout_width="fill_parent"
             android:layout_height="fill_parent"
             android:clickable="true"
             android:enabled="true"
             android:apiKey="api key here" />