这是修改后的答案，请参阅下面的原始答案以供参考：
有了新的更新，这应该会更好，如果您有旧版本，您也需要更新谷歌地图的 cn1lib。我们还再次修改了MapLayout 类，并添加了对齐等一些功能：
public class MapLayout extends Layout implements MapListener {
private static final String COORD_KEY = "$coord";
private static final String POINT_KEY = "$point";
private static final String HORIZONTAL_ALIGNMENT = "$align";
private static final String VERTICAL_ALIGNMENT = "$valign";
private final MapContainer map;
private final Container actual;
private boolean inUpdate;
private Runnable nextUpdate;
private int updateCounter;
public static enum HALIGN {
LEFT {
@Override
int convert(int x, int width) {
return x;
}
},
CENTER {
@Override
int convert(int x, int width) {
return x - width / 2;
}
},
RIGHT {
@Override
int convert(int x, int width) {
return x - width;
}
};
abstract int convert(int x, int width);
}
public static enum VALIGN {
TOP {
@Override
int convert(int y, int height) {
return y;
}
},
MIDDLE {
@Override
int convert(int y, int height) {
return y + height / 2;
}
},
BOTTOM {
@Override
int convert(int y, int height) {
return y + height;
}
};
abstract int convert(int y, int height);
}
public MapLayout(MapContainer map, Container actual) {
this.map = map;
this.actual = actual;
map.addMapListener(this);
}
@Override
public void addLayoutComponent(Object value, Component comp, Container c) {
comp.putClientProperty(COORD_KEY, (Coord) value);
}
@Override
public boolean isConstraintTracking() {
return true;
}
@Override
public Object getComponentConstraint(Component comp) {
return comp.getClientProperty(COORD_KEY);
}
@Override
public boolean isOverlapSupported() {
return true;
}
public static void setHorizontalAlignment(Component cmp, HALIGN a) {
cmp.putClientProperty(HORIZONTAL_ALIGNMENT, a);
}
public static void setVerticalAlignment(Component cmp, VALIGN a) {
cmp.putClientProperty(VERTICAL_ALIGNMENT, a);
}
@Override
public void layoutContainer(Container parent) {
int parentX = 0;
int parentY = 0;
for (Component current : parent) {
Coord crd = (Coord) current.getClientProperty(COORD_KEY);
Point p = (Point) current.getClientProperty(POINT_KEY);
if (p == null) {
p = map.getScreenCoordinate(crd);
current.putClientProperty(POINT_KEY, p);
}
HALIGN h = (HALIGN)current.getClientProperty(HORIZONTAL_ALIGNMENT);
if(h == null) {
h = HALIGN.LEFT;
}
VALIGN v = (VALIGN)current.getClientProperty(VERTICAL_ALIGNMENT);
if(v == null) {
v = VALIGN.TOP;
}
current.setSize(current.getPreferredSize());
current.setX(h.convert(p.getX() - parentX, current.getWidth()));
current.setY(v.convert(p.getY() - parentY, current.getHeight()));
}
}
@Override
public Dimension getPreferredSize(Container parent) {
return new Dimension(100, 100);
}
@Override
public void mapPositionUpdated(Component source, int zoom, Coord center) {
Runnable r = new Runnable() {
public void run() {
inUpdate = true;
try {
List<Coord> coords = new ArrayList<>();
List<Component> cmps = new ArrayList<>();
int len = actual.getComponentCount();
for (Component current : actual) {
Coord crd = (Coord) current.getClientProperty(COORD_KEY);
coords.add(crd);
cmps.add(current);
}
int startingUpdateCounter = ++updateCounter;
List<Point> points = map.getScreenCoordinates(coords);
if (startingUpdateCounter != updateCounter || len != points.size()) {
// Another update must have run while we were waiting for the bounding box.
// in which case, that update would be more recent than this one.
return;
}
for (int i=0; i<len; i++) {
Component current = cmps.get(i);
Point p = points.get(i);
current.putClientProperty(POINT_KEY, p);
}
actual.setShouldCalcPreferredSize(true);
actual.revalidate();
if (nextUpdate != null) {
Runnable nex = nextUpdate;
nextUpdate = null;
callSerially(nex);
}
} finally {
inUpdate = false;
}
}
};
if (inUpdate) {
nextUpdate = r;
} else {
nextUpdate = null;
callSerially(r);
}
}
}
原答案：
当您点击它时，标记将显示文本。如果您希望事物以不同的方式出现，您可以使用任何组件并将其放在地图顶部。即将发布的Uber tutorial 将对此进行深入介绍，但我在这篇博文中解释了基本系统：https://www.codenameone.com/blog/tip-map-layout-manager.html