I am new to flutter and I want to know if there are any event listeners or methods to process off-screen tiles, thank you.
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i'm looking for create a grid of 1000*1000 box. User should be able to click on one and zoom in. Do anyone knows a material to do so ?
I tried to do a gridview, way to long to be initialize for only 2000 unity
Thanks for reading
If performance is a problem, use a CustomPainter and a GestureDetector to handle painting and gesture detection manually. Make sure that you only paint the boxes which are visible on screen.
I'm implementing map exporting functionality using OpenLayers 3.
But there is one problem: one cannot determine whether the map view is completely loaded or a few tiles is missing yet.
It seems there is no such API or event. The close one is tileloadstart - tileloadend pair. But OpenLayers loads tiles asynchronously, and before the tile is actually loading the tileloadstart is not fired - that is, a tile that is queued in the tile queue does not fire the event before actually loading.
Hot can I detect the map view is completely loaded?
postrender event seems to do the trick, like this:
map.once('postrender', function(event) {
doyourmagic();
});
Works at least from OpenLayers 3.8.2. There is fine answer there about the subject.
I eventually implemented the export function successfully. Below is the rough explanation.
Register tileloadstart, tileloadend, tileloaderror event handlers on the ol.sources using ol.source.on(), and start managing the tile load count.
Register postcompose event handlers on the ol.Map using ol.Map.once().
call ol.Map.renderSync(). This triggers the tile loading, so from now if there is no tile loading, it will mean that all tile have been loaded.
On postcompose event handler, capture the map content from event.context using event.context.canvas.toDataURL(), and register postrender function using event.frameState.postRenderFunctions.push() (a bit hacky).
On the registered postrender function, check the tile load count (which can be managed by the tileload* event handlers). If the count is not zero, abandon the captured content. Else, the capture is done.
On tileloadend and tileloaderror, if the tile load count becomes zero, retry from the step 3 above.
Meanwhile, OpenLayers provides a much sought after rendercomplete event which may be handy.
Basically to make sure everything is rendered on your map you need to listen for loadend events for each layer you have on the map. For wms and wfs layers this is clear and I guess you know how to do it.
For the tile layers , check this example here
When "listening" to touchEnd event of a View, how can I determine weather the touch ended inside it's bounds?
in other words, the equivalent of the iOS touchUpInside.
Note-
I'm adding a touchEnd handler and not only on.click because iOS devices have this 300 ms intentional delay and I would like to eliminate it (please point out if there is a better solution to this).
Regarding the event handling, Rikulo UI doesn't handle specially but adding a thin layer on top of what Dart API provides. After all, a view is simply a DIV element with some special attributes.
Here is the list of events we wrapped: Rikulo events. If there is a miss, please let us know (by posting an issue to Github).
Regarding simulation of touchUpInside, this one might help.
I am thinking about developing a BB app that is based on maps provided by BB.
The trick is that I need the markers on the map to be clickable.
I did a little research and a lot of people are saying that this is not possible.
Has anyone done it so he can point me to the right direction?
Thanks in advance.
http://www.wikitude.com -> this application does.
You can extend the MapField class, and then handle the interaction with your markers internally in your class (paint() and touchEvent() should be overridden).
Or eventually, as with many UI-classes, you can do "impossible" things just by painting them on a Bitmap, and manipulating it before rendering on screen.
I'm playing with live tiles on Mango and it's all nice and all. User can delete secondary tiles and everything, but if the user "unpins" a secondary tile is there a way to know that tile is gone?
I want to persist data about an object when it's pinned. And I want to be able to delete that data when it's unpinned (from the start menu).
Is there something that's fired when a secondary tile tied to your app is unpinned?
There is no event that is fired when the secondary tile is unpinned. However, you can check for your application's active live tiles by querying the ShellTile.ActiveTiles collection. Not knowing your scenario you could run this check during the various application lifecycle events.
There is a decent screen cast on how to update tiles and use secondary tiles over on http://msdev.com as well as a How-To on MSDN. Both of these show examples of using the ShellTile.ActiveTiles API.