Is it possible to detect and hook into the events "like"
onBeforeZoomChange and
onAfterZoomChange(="zoom_changed")
There is the problem with hundreds of DIVs (labels) layered on the map
and bound to the appropriate markers. When the map animates (zoom-out),
DIVs changed their size twice and then are animated to be smaller.
It seems to be a great performance problem and very poor behavior.
Is it possible to hide these DIVs before zoom starts and show them
in the zoom_changed ?
There is no way to intercept the methods that redraw the map, but there is a way to intercept the drawing of custom Overlays, because you define the function that draws the Overlay on your own.
The draw-method of a cutom Overlay will be called automatically anytime it is necessary.
Simple approach: don't redraw the Overlay until the map is idle:
YourOverlayClass.prototype.draw = function(idle) {
if(!idle){
var _this=this;
google.maps.event.addListenerOnce(this.map,'idle',
function(){_this.draw(true);});
/*optionally you may hide the overlay here*/
return;
}
/**
* your drawing-instructions here
**/
/*show the overlay here when it has been hidden before*/
}
The automatically call of draw will be done without an argument, the suggestion checks if there was an argument provided,
when yes: it redraws the overlay.
When no: it adds a listener to the idle-event of the map, where the draw-method will be called with an argument(what will redraw the overlay)
Related
I'am using reactJS and want to design a component with following functionality :
Display pixelated image which is able to zoom in and zoom out at pixel level.
When clicked on image , display a marker- which can be a dot or icon at specific position.
When image is zoomIn/zoomOut, marker size and position should not change.
Even after zoomIn/zoomOut when clicked on image, marker should get repositioned at proper pixel on the image.
I am thinking of applying same logic as used in the maps/ leaflet. Like they maintain separate layers for map and markers on the map. If we zoomIn/out maps it won't affect the marker position or size, same functionality I want for the image.
Anyone with the solution or related library will be welcomed !
(For reference, I want this design for marking GCP(Ground Control Points) on the image, which requires very precise marking at pixel level)
I am developing an app in which I have a Map control! On this map, I am adding custom pushpins via map.Children property. How can I set a LocationRectangle and then zoom on it? Because I want my pushpins not to be out of the screen size. I want the map to zoom on a level in which all of the pins will be on the screen!
You can use the MapControl's TrySetViewBoundsAsync method. This method allows you to specify a bounding box of the area you want to display (which you can calculate by finding the the farthest pushpins in all directions, which will give you the north-west and south-east corner of the area), a potential margin and a map animation to use while the view is being changed.
You can find more details about the method in the documentation.
I understand that google.maps.Marker can have a title set to them in their options, can the same be done for google.maps.Circle?
I've tried just setting title on the google.maps.CircleOptions object, but that doesn't seem to do anything.
Is there a way I can give the circle overlays a title? I imagine there is, as when you hover over a circle, the cursor is changed to pointer so there must be some kind of detection there. I don't want to make my own custom tooltip and attach it to the hover event on the circle, I want to use the browser's built in title hover.
Circles:
https://developers.google.com/maps/documentation/javascript/overlays#Circles
CircleOptions object: https://developers.google.com/maps/documentation/javascript/reference#CircleOptions
It is not currently possible to add a title to a circle. As you can see from the CircleOptions, it doesn't list 'title' as a option that you can use.
A work around could be to listen to the mousemove event on the circle then to show your own title as a custom OverlayView
Hi i'm trying to get a photoshop-like behaviour for my QGraphicsScene
The grid in the background should not resize with the call of scale. And I must be able to save the picture with QPixmap::grabWidget(view) but without the background grid. I can probably do it with removing the background layer just before saving the picture, but i'm not sure if its cleanest way to do it.
Any ideas ?
thx.
Question 1
The grid in the background should not resize with the call of scale.
Use the QGraphicsItem::ItemIgnoresTransformations flag.
The item ignores inherited transformations (i.e., its position is
still anchored to its parent, but the parent or view rotation, zoom or
shear transformations are ignored). This flag is useful for keeping
text label items horizontal and unscaled, so they will still be
readable if the view is transformed. When set, the item's view
geometry and scene geometry will be maintained separately.
In order to set this flag use the setFlag function when creating the grid item.
Question 2
I must be able to save the picture with QPixmap::grabWidget(view) but without the
background grid.
Call the hide function on the grid item before calling the grabWidget. After you have grabbed it you show it again by calling the show function.
Please help me to change size of openInfoWindowHtml in google map and plez tell me can i make it popup out of map area also..? i mean my map area is very small but i want that when user click on Marker this openInfoWindowHtml should show popup and if its crossing size of map than its should show beyond the boundary of google map. ( i am working in asp.net)
There are 2 ways that you can influence the size of the InfoWindow. First, you can pass a GInfoWindowOptions object when you call openInfoWindowHtml (see: http://code.google.com/apis/maps/documentation/reference.html#GInfoWindowOptions) Second, you can wrap the contents of the InfoWindow in a div and use CSS to set the size of that div.
Regardless of which method you use to set the size of the InfoWindow, it can never exceed the bounds of the map canvas (area).