我已经尝试解决这个看似简单的问题了大约半天.我有一个工作的MapView,我只想显示默认的缩放键,并一直将它们放在那里.它们根本不会出现-不是因为它们出现然后消失了.

码：

public void onCreate( Bundle savedInstanceState ) 
{
    super.onCreate( savedInstanceState );

    setContentView( R.layout.main );

    _altDisplay = (TextView) findViewById( R.id.altitudeDisplay );
    _speedDisplay = (TextView) findViewById( R.id.speedDisplay );
    _accuracyDisplay = (TextView) findViewById( R.id.accuracyDisplay );

    _mapView = (MapView) findViewById( R.id.mapView );
    _mapView.setBuiltInZoomControls(true);

    _mapController = _mapView.getController();
    _mapController.setZoom(22);

    _locationUpdates = new LocationUpdateHandler( (LocationManager) getSystemService( Context.LOCATION_SERVICE) );
    _locationUpdates.addObserver( this );
}

public void updateLocation( GeoPoint point,double altitude,float speed,float accuracy )
{
    _mapController.setCenter(point);

    _altDisplay.setText( "Altitude: " + Double.toString(altitude) );
    _speedDisplay.setText( "Speed: " + Float.toString(speed) );
    _accuracyDisplay.setText( "Accuracy: " + Float.toString(accuracy) );
}

我尝试注释掉setZoom,并尝试将setBuiltInZoom控件移至updateLocation方法.我发现了很多与此问题相关的帖子,但都没有解决该问题的帖子.

谢谢你的帮助.