Is there a function that allows specifying default padding values for different edges of the MapFragment, i.e. similar to
CameraUpdateFactory.newLatLngBounds(LatLngBounds bounds, int padding)
which already exists, but instead something like
CameraUpdateFactory.newLatLngBounds(LatLngBounds bounds, int paddingTop, int paddingLeft, int paddingBottom, int paddingRight)?
Why I need this: In my MapFragment I have a half transparent layer on top. Therefore I need a wider padding at the top than at the bottom.
I found this similar question: Offseting the center of the MapFragment for an animation moving both the target lat/lng and the zoom level. However, getting the projection and scrolling by X pixels is not enough in my case, because I don't only want to scroll (pan). I use a CameraUpdate with newLatLngBounds(bounds, padding), which is supposed to both zoom and pan. So I have a different projection before the camera update.
I hope I made the question clear!
This is an example of set padding to map...
Sets padding on the map.
This method allows you to define a visible region on the map, to signal to the map that portions of the map around the edges may be obscured, by setting padding on each of the four edges of the map. Map functions will be adapted to the padding. For example, the zoom controls, compass, copyright notices and Google logo will be moved to fit inside the defined region, camera movements will be relative to the center of the visible region, etc.
*the size is in pixels
GoogleMap.setPadding( 10, 20, 20, 50);
all are Int left, top, right, bottom
from #MaciejGorsky, here is the documentation...
https://developers.google.com/android/reference/com/google/android/gms/maps/GoogleMap?hl=pl#setPadding(int, int, int, int)
Related
Given a MapFragment with any zoom level at any time, is it possible to detect the area covered by the map?
For instace, I'm at Lat: 38.766667 and Lon: -9.15 with the zoom level at 15.0f, how do I calculate the area covered or how do I obtain the top left corner and bottom right coordinates?
you can get the corners of the view area by doing:
googleMap.getProjection().getVisibleRegion().
//farLeft;
//farRight;
//nearLeft;
//nearRight;
//or
//latLngBounds;
Keep in mind that if you have tilting/inclined view the real view area is not a rectangle but a trapezoid.
Have a look at the documentation here to check what is best for you, latLngBounds gives the "smallest" rectangle, that is not the exact area!
https://developers.google.com/android/reference/com/google/android/gms/maps/model/VisibleRegion
It's not easy explaining my problem but I will try.
I have an android GoogleMap, on top of it, I have an ImageView positioned at its center at all times. If I drag/pan the map, the pin will always be in the center of the GoogleMap.
Now, I add a marker, somewhere on the map. I want to zoom such that the center point remains in the center of the map, and the marker is visible within the map, and to the highest zoom level.
The problem is if I simply check if the marker is within boundaries of the map or not, and then keep zooming in/out till it is, this process will always repeat itself, i.e. trying to zoom in and if the marker became outside, then zoom out.
The problem is I rely on an OnCameraChange listener which will keep calling itself everytime I zoom in or out, hence, the process of zooming in/out will keep occuring indefinitely
journeyGoogleMap.setOnCameraChangeListener(new OnCameraChangeListener()
{
#Override
public void onCameraChange(final CameraPosition position)
{
Basically, what I need is a function where I can provide the center LatLng and the markerLatLng and it will automatically calculate the LatLngBounds making sure my center is within the center of the LatLng bounds, and then I can simply use
public static CameraUpdate newLatLngBounds (LatLngBounds bounds, int width, int height, int padding)
as shown in the link below
https://developers.google.com/maps/documentation/android/reference/com/google/android/gms/maps/CameraUpdateFactory#newLatLngBounds(com.google.android.gms.maps.model.LatLngBounds,int, int,int)
If you need anymore clarification please do tell me
You need to calculate LatLngBounds from two points:
Your marker position and
Place on the opposite side of your current center.
The second is calculated like this:
LatLng other = new LatLng(2 * center.latitude - position.latitude, 2 * center.longitude - position.longitude);
See LatLngBoundsUtils.fromCenterAndPositions for a general solution.
Use googleMap.getProjection().getVisibleRegion() to get all four corners of screen as LatLng values forming trapezium. Calculate where trapezium intersects with line drawn through center and your marker. Scale factor is (distance from center to marker / distance from center to intersection point). Now just scale trapezium with this scale factor relative to center. This is new visible regison.
You may also use getVisibleRegion().latLngBounds to simplify calculation, but note that some areas of returned rectangle are actually not visible.
I need to apply click/touch events for only visible part of the View. Say for example a image of size 200X200. Apart from center 50X50, remaining part is transparent. I want to get touch events only for that 50X50 visible part Not on remaining transparent part.
In above image (its single image), only inner Diamond has got visible part. Apart from that Diamond is transparent area. So, if I touch Diamond then only I want to do something else ignore.
Edit :
Rachita's link helped me. I gone through that link and got idea how can I implement. But I could not understand some constants like 320, 240 etc while creating Points. In my case, I know the Diamond (in above image) x and y Ponits (hard coded values asctually). So, using those how can I determine, whether I touched inside Diamond or outside?
my Diamond points are as below
pointA = new Point(0, 183);
pointB = new Point(183, 0);
pointC = new Point(366, 183);
pointD = new Point(183, 366);
Edit :
Finally got solution from Luksprog. Its based on checking touched point pixel color. If color is 0 means, you touched transparent layer else you touched some colored part of the image. Simple, but very effective. Have a look at it here.
AFAIK you can not implement this with onclick listener or my any other direct way .You will have to use onTouchListener .
Firstly set your view dynamically at a specific (x,y) position using this How can I dynamically set the position of view in Android?
Calculate the region your diamond will occupy (you should khow the size of image inorder to calculate area of diamond)
3.Trigger a action in onTouchListener only when x, y fall in the required region. Use How to get the Touch position in android?
check this link to calculate if a given point lies in the required square
EDIT
To understand the coordinate system of android refer to this link How do android screen coordinates work?
Display mdisp = getWindowManager().getDefaultDisplay();
int maxX= mdisp.getWidth();
int maxY= mdisp.getHeight();
(x,y) :-
1) (0,0) is top left corner.
2) (maxX,0) is top right corner
3) (0,maxY) is bottom left corner
4) (maxX,maxY) is bottom right corner
here maxX and maxY are screen maximum height and width in pixels, which we have retrieved in above given code.
Remember if you want to support multiple devices with different screen sizes,make sure you use a relative value for x,y ie some ratio of screen height or width ,as different devices have different ppi
Check if touched point lies in the required polygon
I thinks these link might help you determining if the point touched (you can get x,y from onTouch event eg.event.getX()) lies in the required polygon whose points you have mentioned in the question . determine if a given point is inside the polygon and How can I determine whether a 2D Point is within a Polygon?
i have 5 markers to display on the map, out of which 4 are very near to each other and the fifth one is a little bit distant to these 4. now when i display the map i want all these 5 markers to be shown on map and the with the highest possible zoom. i dont care whether they are on the border of the screen or in the center of the screen.i mean the markers can be scattered on the screen but all i want is that all markers should visible to the user and with the highest possible zoom.
i have tried this Android map v2 zoom to show all the markers . but the result is that it is showing all markers at the center of the map with very little zoom. actually i have calculated screen dimensions using this code.
DisplayMetrics metrics=new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
float height=metrics.heightPixels/metrics.xdpi;
float width=metrics.widthPixels/metrics.ydpi;
but i dont know why there is very little zoom. But wen i saw android documentation, i think the function is doing justice by doing whatever it said it will do.
public static CameraUpdate newLatLngBounds (LatLngBounds bounds, int width, int height, int padding)
Returns a CameraUpdate that transforms the camera such that the specified
latitude/longitude bounds are centered on screen within a bounding box of specified
dimensions at the greatest possible zoom level. You can specify additional padding,
to further restrict the size of the bounding box. The returned CameraUpdate has a
bearing of 0 and a tilt of 0.
Unlike newLatLngBounds(LatLngBounds, int), you can use the CameraUpdate returned by
this method to change the camera prior to the map's the layout phase, because the
arguments specify the desired size of the bounding box.
as it says it keeps all the markers at the center of the map. i do not want that. i want all the markers visible to the user with the maximum possible zoom and markers scattered. can anybody please help me?
Your calculation of float width and height is incorrect.
What your width holds now is inches (value of approx. 2 on phones). You need not to divide pixels width.
Android Question.
I have made a custom ImageView class and inside it I have an onDraw method which will draw a circle on particular pixels (using canvas). When I use this custom imageview and open up my image I would like to set the focus on the circle that I have drawn (e.g like google maps do with your current location. The focus is set to your current point)
What the map server does on google is deliver a customized set of tiles so that the center is displayed properly, the newer version is of course vector based so they simply draw the view so it's centered where they want it.
Without knowing the details of your application you probably need
Create your own container class, probably FrameLayout
public class myMapFrameLayout extends FrameLayout {
The override either onDraw or onDispatchDraw so that you can layout your tile appropriately
Figure out where to draw your bitmap so that the x,y you need will be in the center of the screen, then draw the other tiles that you need to fill in the blank space at the coordinates required dependent on which way the tile was moved to get centered
Think of a virtual screen that is larger than the actual screen with tiles all around it that are the same size
1 2 3
4 X 5
6 7 8
Assuming that X is the size of the display and represents the current tile you need to figure out which way to move the tile, and which other tiles 1,2,3,4,5,6,7 or 8 you need to fill in the empty space caused by move
If you had to draw the tile +x from 0,0 you need some of tile 4, drawing +y from 0,0 means some of 2 and both mean 1,2,4 are all needed and so on, so figure out the combinations and load the tiles you need, and figure out the drawing positions of each. That would give you your new virtual tile with the center displayed.
That's about as efficient as you can get I think with a bitmap drawing method on the client side.
UPDATE
Since your comment indicates you have only one very large image this is going to be a bit of a problem if the x,y you need as anything closer to the edges than the size of the display
None the less you can still draw the image where you need it, just measure the screen and draw the bitmap with the target x,y in the center
So if the screen was 500x500 and your image was 5000x5000 and the center was at position x=1000 y=1000 then
drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint)
where source rectangle would be 1000-250,1000-250,500,500 and dst rectangle would be 0,0,500,500
The 250 is the center x and center y of the display, 1000 are the target x/y coordinates, and 500 is the size of display.
Again, with targets that are at the edges you are going to have a blank polygon in your screen since you dont have an infinite map tile
Alternatively you could oversize your framelayout using layoutparams and just translate the canvas in the x and y to get the canvas centered to the x,y you need using similar calcs which may be more performant, not really sure
Keep in mind you are going to be using a lot of memory if your image is really big