android地图:如何长期点击地图?

时间:2009-11-05 05:15:56

标签: android android-mapview long-click

如何长时间点击地图视图,以便在地图上的该点显示地点标记?

我尝试了几种方法却没有成功:

1)在从未检测到长片的setOnLongClickListener上使用MapvView

2)我的另一个想法是将MapView扩展为覆盖dispatchTouchEvent。创建一个GestureDetector来响应longpress回调。但我被困在中途,因为我无法处理我的子类Mapview。即。

MyMapview mymapview; //MyMapView extends MapView

//results in a classcast exception
mymapView = (MyMapView) findViewById(R.id.map);

3)我知道如何尝试这个的唯一方法是: 检测MotionEvent.ACTION_DOWN并将延迟的runnable发布到处理程序,并检测longpress是否还有其他两个事件:acton_move或action_up。

有人可以提供任何这些检测长按的方法吗?

8 个答案:

答案 0 :(得分:22)

我找到了一种更简单的方法。只需将叠加层作为列表中第一个不绘制任何内容的叠加层,并使用它来使用GestureDetector识别手势。如果它处理事件,它应该返回true,因此它不会被传播。

    List<Overlay> overlays = mapView.getOverlays();
    overlays.clear();
    overlays.add(new MapGestureDetectorOverlay(new MyOnGestureListener()));

这是班级:

public class MapGestureDetectorOverlay extends Overlay implements OnGestureListener {
 private GestureDetector gestureDetector;
 private OnGestureListener onGestureListener;

 public MapGestureDetectorOverlay() {
  gestureDetector = new GestureDetector(this);
 }

 public MapGestureDetectorOverlay(OnGestureListener onGestureListener) {
  this();
  setOnGestureListener(onGestureListener);
 }

 @Override
 public boolean onTouchEvent(MotionEvent event, MapView mapView) {
  if (gestureDetector.onTouchEvent(event)) {
   return true;
  }
  return false;
 }

 @Override
 public boolean onDown(MotionEvent e) {
  if (onGestureListener != null) {
   return onGestureListener.onDown(e);
  }
  return false;
 }

 @Override
 public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
   float velocityY) {
  if (onGestureListener != null) {
   return onGestureListener.onFling(e1, e2, velocityX, velocityY);
  }
  return false;
 }

 @Override
 public void onLongPress(MotionEvent e) {
  if (onGestureListener != null) {
   onGestureListener.onLongPress(e);
  }
 }

 @Override
 public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
   float distanceY) {
  if (onGestureListener != null) {
   onGestureListener.onScroll(e1, e2, distanceX, distanceY);
  }
  return false;
 }

 @Override
 public void onShowPress(MotionEvent e) {
  if (onGestureListener != null) {
   onGestureListener.onShowPress(e);
  }
 }

 @Override
 public boolean onSingleTapUp(MotionEvent e) {
  if (onGestureListener != null) {
   onGestureListener.onSingleTapUp(e);
  }
  return false;
 }

 public boolean isLongpressEnabled() {
  return gestureDetector.isLongpressEnabled();
 }

 public void setIsLongpressEnabled(boolean isLongpressEnabled) {
  gestureDetector.setIsLongpressEnabled(isLongpressEnabled);
 }

 public OnGestureListener getOnGestureListener() {
  return onGestureListener;
 }

 public void setOnGestureListener(OnGestureListener onGestureListener) {
  this.onGestureListener = onGestureListener;
 }
}

答案 1 :(得分:8)

我知道这样做的最好方法是使用开源mapview-overlay-manager并使用其提供回调的手势监听器

public void onLongPress(MotionEvent e, ManagedOverlay overlay)

答案 2 :(得分:4)

答案 3 :(得分:4)

这适用于您的MapActivity,并允许您:

  1. 为地图上的长按设置自己的时间阈值(0.8 秒对我来说很好)。
  2. 长按不解释滚动,多点触控或非多点触控事件。它还可以让你为某人的手指设置容差     他们按住长按,在屏幕上稍微移动一下。

  3. 此解决方案基于Roger Kristiansen's solution。我添加了x和y点检测,这样滚动就不会被视为长按。这个解决方案并不像Roger那样优雅,因为我使用类变量并将代码放在我现有的MapActivity中,而不是像他那样扩展MapView并创建一个监听器。但是如果你想坚持他的代码,但有更好的非多点触控支持,只需将x和y点的东西拿出来并添加到他的。


    在MapActivity顶部设置的类变量:

    //variable for determining long press and then automatically adding a pin to the map
    private int minMillisecondThresholdForLongClick = 800;
    private long startTimeForLongClick = 0;
    private float xScreenCoordinateForLongClick;
    private float yScreenCoordinateForLongClick;
    private float xtolerance=10;//x pixels that your finger can be off but still constitute a long press
    private float ytolerance=10;//y pixels that your finger can be off but still constitute a long press
    private float xlow; //actual screen coordinate when you subtract the tolerance
    private float xhigh; //actual screen coordinate when you add the tolerance
    private float ylow; //actual screen coordinate when you subtract the tolerance
    private float yhigh; //actual screen coordinate when you add the tolerance
    

    在MapActivity中添加此功能:

        @Override
        public boolean dispatchTouchEvent(MotionEvent ev) {
            /* We want to capture the place the user long pressed on the map and add a marker (pin) on the map at that lat/long.
             * This solution:
             *  1. Allows you to set the time threshold for what constitutes a long press
             *  2. Doesn't get fooled by scrolling, multi-touch, or non-multi-touch events
    
             * Thank you Roger Kind Kristiansen for the main idea
             */     
    
            //get the action from the MotionEvent: down, move, or up
            int actionType = ev.getAction();
    
            if (actionType == MotionEvent.ACTION_DOWN) {
                //user pressed the button down so let's initialize the main variables that we care about:
                // later on when the "Action Up" event fires, the "DownTime" should match the "startTimeForLongClick" that we set here  
                // the coordinate on the screen should not change much during the long press
                startTimeForLongClick=ev.getEventTime();
                xScreenCoordinateForLongClick=ev.getX();
                yScreenCoordinateForLongClick=ev.getY();
    
            } else if (actionType == MotionEvent.ACTION_MOVE) {
                //For non-long press actions, the move action can happen a lot between ACTION_DOWN and ACTION_UP                    
                if (ev.getPointerCount()>1) {
                    //easiest way to detect a multi-touch even is if the pointer count is greater than 1
                    //next thing to look at is if the x and y coordinates of the person's finger change.
                    startTimeForLongClick=0; //instead of a timer, just reset this class variable and in our ACTION_UP event, the DownTime value will not match and so we can reset.                        
                } else {
                    //I know that I am getting to the same action as above, startTimeForLongClick=0, but I want the processor
                    //to quickly skip over this step if it detects the pointer count > 1 above
                    float xmove = ev.getX(); //where is their finger now?                   
                    float ymove = ev.getY();
                    //these next four values allow you set a tiny box around their finger in case
                    //they don't perfectly keep their finger still on a long click.
                    xlow = xScreenCoordinateForLongClick - xtolerance;
                    xhigh= xScreenCoordinateForLongClick + xtolerance;
                    ylow = yScreenCoordinateForLongClick - ytolerance;
                    yhigh= yScreenCoordinateForLongClick + ytolerance;
                    if ((xmove<xlow || xmove> xhigh) || (ymove<ylow || ymove> yhigh)){
                        //out of the range of an acceptable long press, reset the whole process
                        startTimeForLongClick=0;
                    }
                }
    
            } else if (actionType == MotionEvent.ACTION_UP) {
                //determine if this was a long click:
                long eventTime = ev.getEventTime();
                long downTime = ev.getDownTime(); //this value will match the startTimeForLongClick variable as long as we didn't reset the startTimeForLongClick variable because we detected nonsense that invalidated a long press in the ACTION_MOVE block
    
                //make sure the start time for the original "down event" is the same as this event's "downTime"
                if (startTimeForLongClick==downTime){ 
                    //see if the event time minus the start time is within the threshold
                    if ((eventTime-startTimeForLongClick)>minMillisecondThresholdForLongClick){ 
                        //make sure we are at the same spot where we started the long click
                        float xup = ev.getX();                  
                        float yup = ev.getY();
                        //I don't want the overhead of a function call:
                        xlow = xScreenCoordinateForLongClick - xtolerance;
                        xhigh= xScreenCoordinateForLongClick + xtolerance;
                        ylow = yScreenCoordinateForLongClick - ytolerance;
                        yhigh= yScreenCoordinateForLongClick + ytolerance;
                        if ((xup>xlow && xup<xhigh) && (yup>ylow && yup<yhigh)){ 
    
                            //**** safe to process your code for an actual long press **** 
                            //comment out these next rows after you confirm in logcat that the long press works
                            long totaltime=eventTime-startTimeForLongClick;
                            String strtotaltime=Long.toString(totaltime);                               
                            Log.d("long press detected: ", strtotaltime);
    
    
                            /* 
                            //Now get the latitude/longitude of where you clicked.  Replace all the code below if you already know how to translate a screen coordinate to lat/long.  I know it works though.
    
                            //*****************
                            //I have my map under a tab so I have to account for the tab height and the notification bar at the top of the phone.  
                            // Maybe there are other ways so just ignore this if you already know how to get the lat/long of the pixels that were pressed.
                            int TabHeightAdjustmentPixels=tabHost.getTabWidget().getChildAt(0).getLayoutParams().height;
                            int EntireTabViewHeight = tabHost.getHeight();
                            Display display = getWindowManager().getDefaultDisplay(); 
                            int EntireScreenHeight = display.getHeight();
                            int NotificationBarHeight=EntireScreenHeight-EntireTabViewHeight;
                            //the projection is mapping pixels to where you touch on the screen.
                            Projection proj = mapView.getProjection();
                            GeoPoint loc = proj.fromPixels((int)(ev.getX(ev.getPointerCount()-1)), (int)(ev.getY(ev.getPointerCount()-1)-TabHeightAdjustmentPixels-NotificationBarHeight)); 
                            int longitude=loc.getLongitudeE6();             
                            int latitude=loc.getLatitudeE6();
                            //*****************
    
                            //**** here's where you add code to: 
                            // put a marker on the map, save the point to your SQLite database, etc
                            */
    
                        }
                    }
                }
    
            }
    
    
            return super.dispatchTouchEvent(ev);
        }
    

答案 4 :(得分:3)

这个mapview-overlay-manager库是超级的。 '滚动'时onLongPress被触发的原因是因为库没有考虑多点触控。如果涉及多个指针,则可以通过拒绝onLongPress来解决此问题:

public void onLongPress(MotionEvent motionEvent, ManagedOverlay arg1) {

    if (motionEvent.getPointerCount() > 1) return;

    ... your logic here ...
}

答案 5 :(得分:2)

安布罗斯

我修改了库mapview-overlay-manager的演示。使用双击手势运行此代码:

package de.android1.overlaymanager.demo;

import android.os.Bundle;
import android.widget.Toast;
import android.graphics.drawable.Drawable;
import android.view.MotionEvent;
import com.google.android.maps.MapActivity;

import com.google.android.maps.MapView;
import com.google.android.maps.MapController;
import com.google.android.maps.GeoPoint;

import de.android1.overlaymanager.*;


public class DemoView extends MapActivity {

    MapView mapView;
    MapController mapController;

    OverlayManager overlayManager;

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

        mapView = (MapView) findViewById(R.id.mapview);
        mapView.setBuiltInZoomControls(true);
        mapController = mapView.getController();

        overlayManager = new OverlayManager(getApplication(), mapView);
    }

    @Override
    public void onWindowFocusChanged(boolean b) {

         createOverlayWithListener();

    }


    public void createOverlayWithListener() {
        //This time we use our own marker
        final ManagedOverlay managedOverlay = overlayManager.createOverlay("listenerOverlay", getResources().getDrawable(R.drawable.marker));
        for (int i = 0; i < 40; i = i + 3) {
            managedOverlay.createItem(GeoHelper.geopoint[i], "Item" + i);
        }
        managedOverlay.setOnOverlayGestureListener(new ManagedOverlayGestureDetector.OnOverlayGestureListener() {


            public boolean onZoom(ZoomEvent zoom, ManagedOverlay overlay) {
                return false;
            }


            public boolean onDoubleTap(MotionEvent e, ManagedOverlay overlay, GeoPoint point, ManagedOverlayItem item) {
                Drawable defaultmarker = getResources().getDrawable(R.drawable.marker);     

                ManagedOverlay managedOverlay = overlayManager.createOverlay(defaultmarker);

                //creating some marker:
                managedOverlay.createItem(point);

                //registers the ManagedOverlayer to the MapView
                overlayManager.populate();
                Toast.makeText(getApplicationContext(), "You created a Marker!", Toast.LENGTH_LONG).show();

                return true;
            }


            public void onLongPress(MotionEvent arg0, ManagedOverlay arg1) {
                // TODO Auto-generated method stub

            }


            public void onLongPressFinished(MotionEvent arg0,
                    ManagedOverlay arg1, GeoPoint arg2, ManagedOverlayItem arg3) {
                // TODO Auto-generated method stub

            }


            public boolean onScrolled(MotionEvent arg0, MotionEvent arg1,
                    float arg2, float arg3, ManagedOverlay arg4) {
                // TODO Auto-generated method stub
                return false;
            }


            public boolean onSingleTap(MotionEvent arg0, ManagedOverlay arg1,
                    GeoPoint arg2, ManagedOverlayItem arg3) {
                // TODO Auto-generated method stub
                return false;
            }           
        });
        overlayManager.populate();
    }


    @Override
    protected boolean isRouteDisplayed() {
        return false;
    }
}

希望它有所帮助。

答案 6 :(得分:0)

当我尝试使用MyMapView时,我也遇到了ClassCastException。作为一种解决方法,我创建了一个MyMapView对象而不是MapView对象,并以编程方式将其添加到布局中,并且效果很好。

    MyMapView mapView = new MyMapView(this, this.getString(R.string.APIMapKey));
    mapView.displayZoomControls(false);
    mapView.setClickable(true);
    FrameLayout item = (FrameLayout) findViewById(R.id.getlocationmap);
    item.addView((MapView)mapView);

答案 7 :(得分:0)

如果您将延迟的帖子/消息发送给处理程序(我自己使用的解决方案),测试地图是否已移动(即mapView.getMapCenter()mapView.getLatitudeSpan()是否有用并且mapView.getLongitudeSpan()返回与指针停止时相同的内容。