Android'中覆盖层定位不准确;s地图视图
我正在尝试创建一个包含MapView和ListView的活动。我使用C#和单机器人 布局看起来像这样Android'中覆盖层定位不准确;s地图视图,android,android-mapview,xamarin.android,itemizedoverlay,Android,Android Mapview,Xamarin.android,Itemizedoverlay,我正在尝试创建一个包含MapView和ListView的活动。我使用C#和单机器人 布局看起来像这样 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent"
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<app.MD.UI.PlacesMapView
android:id="@+id/mapView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:enabled="true"
android:clickable="true"
android:layout_weight="1"
android:apiKey="key" />
<ListView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:id="@+id/resultsTable" />
</LinearLayout>
var point = MapHelper.ConvertCoordinates(this.Context, this, e.GetX(), e.GetY());
GeoPoint longpressLocation = Projection.FromPixels(point.X, point.Y);
活动方法,该方法将标记添加到地图视图
protected void AddPinToMap(GeoPoint location, string title, bool scrollTo, int zoom)
{
var pin = Resources.GetDrawable(Resource.Drawable.maps_pin);
PinOverlay pinOverlay = new PinOverlay(pin, this);
OverlayItem item = new OverlayItem(location, title, "");
pinOverlay.AddOverlay(item);
mapView.Overlays.Clear();
mapView.Overlays.Add(pinOverlay);
if (scrollTo) {
mapView.Controller.AnimateTo(location);
}
mapView.Controller.SetZoom(zoom);
}
这是我的皮诺弗雷课
class PinOverlay : ItemizedOverlay
{
private List<OverlayItem> _items = new List<OverlayItem>();
private Context _context;
public PinOverlay(Drawable pin, Context context) : base(pin)
{
_context = context;
BoundCenterBottom(pin);
Populate();
}
protected override Java.Lang.Object CreateItem(int i)
{
return _items[i];
}
public override int Size()
{
return _items.Count();
}
public void AddOverlay(OverlayItem overlay) {
_items.Add(overlay);
Populate();
}
}
您是否尝试过:
public PinOverlay(Drawable pin, Context context)
: base(BoundCenterBottom(pin))
这将使放置在地图中心点上的可绘制
,而不是在绘制时将地理坐标作为(x,y)(0,0)坐标
编辑:
我似乎无法在这里重现您的问题,当在构造函数的:base()
中使用BoundCenterBottom(pin)时,它会将我的可绘制的
居中
我还注意到,在您的AddPinToMap
方法中,每次都会创建一个新的PinOverlay
。这应该不是必需的,您只需将新的OverlayItem
s添加到PinOverlay
,您只需将其添加一次到地图。如果要在地图上添加大量的管脚,这将更高效,资源密集度也更低
所以它看起来应该更像:
protected void AddPinToMap(GeoPoint location, string title, bool scrollTo, int zoom)
{
var pin = Resources.GetDrawable(Resource.Drawable.maps_pin);
OverlayItem item = new OverlayItem(location, title, "");
pinOverlay.AddOverlay(item); // this is instantiated in OnCreate
if (scrollTo) {
mapView.Controller.AnimateTo(location);
}
mapView.Controller.SetZoom(zoom);
}
如果希望能够同时删除覆盖项,请将Remove
方法添加到PinOverlay
另外,MapView
已经有一个LongClick
事件,您可以将其挂接到该事件中,而不是覆盖该类:
var mapView = FindViewById<MapView>(Resource.Id.myMapView);
mapView.LongClick += (sender, args) => { //do whatever in here };
var-mapView=findviewbyd(Resource.Id.myMapView);
mapView.LongClick+=(发送者,参数)=>{//在这里做任何事情};
或
var-mapView=findviewbyd(Resource.Id.myMapView);
mapView.LongClick+=OnLongClick;
private void OnLongClick(对象发送者,LongClickEventArgs LongClickEventArgs)
{
//在这里做什么都行
}
我终于找到了问题的原因
这一部分是错误的,因为投影是在经过的代理内部访问的。但到那时,投影已经改变了它的状态,这导致了错误的坐标
if (e.Action == MotionEventActions.Down) {
// Finger has touched screen.
longpressTimer = new Timer(LONGPRESS_THRESHOLD);
longpressTimer.AutoReset = false;
longpressTimer.Elapsed += delegate(object sender, ElapsedEventArgs e_elapsed) {
GeoPoint longpressLocation = Projection.FromPixels((int)e.GetX(), (int)e.GetY());
if (OnLongPress != null) {
OnMapViewLongPressEventArgs args = new OnMapViewLongPressEventArgs();
args.location = longpressLocation;
OnLongPress(this, args);
}
};
longpressTimer.Start();
lastMapCenter = MapCenter;
}
因此,解决方案是在OnTouchEvent的最开始获得地质点
if (e.Action == MotionEventActions.Down) {
capturedProjection = Projection.FromPixels((int)e.GetX(), (int)e.GetY());
// Finger has touched screen.
longpressTimer = new Timer(LONGPRESS_THRESHOLD);
longpressTimer.AutoReset = false;
longpressTimer.Elapsed += (object sender, ElapsedEventArgs e_timer) => {
if (OnLongPress != null) {
OnMapViewLongPressEventArgs args = new OnMapViewLongPressEventArgs();
args.location = capturedProjection;
OnLongPress(this, args);
}
};
longpressTimer.Start();
lastMapCenter = MapCenter;
}
是的,我试过这种方法,但没什么区别。即使我明确设置了边界,它也只会影响标记阴影的位置。感谢关于PinOverlay的建议。此外,我找不到如何从LongClickEventArgs获取XY,这就是我使用计时器和触摸事件的原因。
var mapView = FindViewById<MapView>(Resource.Id.myMapView);
mapView.LongClick += OnLongClick;
private void OnLongClick(object sender, LongClickEventArgs longClickEventArgs)
{
// do whatever in here
}
if (e.Action == MotionEventActions.Down) {
// Finger has touched screen.
longpressTimer = new Timer(LONGPRESS_THRESHOLD);
longpressTimer.AutoReset = false;
longpressTimer.Elapsed += delegate(object sender, ElapsedEventArgs e_elapsed) {
GeoPoint longpressLocation = Projection.FromPixels((int)e.GetX(), (int)e.GetY());
if (OnLongPress != null) {
OnMapViewLongPressEventArgs args = new OnMapViewLongPressEventArgs();
args.location = longpressLocation;
OnLongPress(this, args);
}
};
longpressTimer.Start();
lastMapCenter = MapCenter;
}
if (e.Action == MotionEventActions.Down) {
capturedProjection = Projection.FromPixels((int)e.GetX(), (int)e.GetY());
// Finger has touched screen.
longpressTimer = new Timer(LONGPRESS_THRESHOLD);
longpressTimer.AutoReset = false;
longpressTimer.Elapsed += (object sender, ElapsedEventArgs e_timer) => {
if (OnLongPress != null) {
OnMapViewLongPressEventArgs args = new OnMapViewLongPressEventArgs();
args.location = capturedProjection;
OnLongPress(this, args);
}
};
longpressTimer.Start();
lastMapCenter = MapCenter;
}