Jody,
sorry for the unclear description.....
------------------what I want---------------------------
App receives a serie of vehicle GPS data, each of which is drew by a filled
circle. But only the last GPS should be displayed on the DirectLayer,
representing the current position of the vehicle
-----------------what I do--------------------------
Step 1 use socket to receive and send vehicle's position (Lon, Lat)
Step 2 extend DirectLayer to GpsDirectLayer, which have an ArrayList to store
all of the GPS point
Step 3 when socket receives the first GPS, get the background image of the GPS
will cover before draw it. This background image contains the map which is
covered by GPS
Step 4 Draw the first GPS by a filled circle
Step 5 When socket receives the second GPS, we need to :
(1) erase the first GPS. Draw the background image, which is saved at step 3.
So the first GPS is covered by this image
(2) Draw the second GPS
-------------------my problem------------------
When PAN and ZOOM, all layers are redrawn (I think). So the background image in
Step 3 is no longer available. I mean, the map GPS covers is moved by PAN or
ZOOM.
------------------How I solve--------------------
when PAN and ZOOM, set this background image to null (so it won't be drawn). So
I have to listen the PAN and ZOOM operation, and set the background image (it
is a member variable of GpsDirectLayer) to null there
I am not sure whether I describe my problem clearly this time
在 2015-03-04 06:05:57，"Jody Garnett" <jody.garn...@gmail.com> 写道：
I am not quite sure what you are stuck on. I guess that setting the background
to null asks the demo to draw it again?
--
Jody Garnett
On 2 March 2015 at 18:19, wbh <wangbaohua2...@163.com> wrote:
Plus, after debug, my idea, that setting the background of the GPS is null
after PAN or ZOOM, solves my problem.
However, I feel this is not the best way.
Can anybody tell me how to solve my problem?
在 2015-03-02 21:41:40，"wbh" <wangbaohua2...@163.com> 写道：
Dears,
I have a simple app which displays the vehicle's current position.
-------------------my way------------------------
1 use socket to receive and send vehicle's position (Lon, Lat)
2 extend DirectLayer to GpsDirectLayer, which have an ArrayList to store all of
the GPS point
3 when socket receives a GPS, add it to the ArrayList and call Draw() method of
GpsDirectLayer. In this method, erase the previous point and draw the latest
GPS. (Thanks Michael Bedward for the FlyingSaucer demo ^^)
4 In eras() method, get the background of the GPS (use Raster) before draw it
-------------------my problem------------------
If no PAN, ZOOM operation, all goes well. But when PAN and ZOOM, all layers are
redrawn (I think). So the stored raster for the background is no longer
available (or needed).
What can I do to avoid this?
My first idea is set the background is null when PAN or ZOOM is performed, is
that the correct way?
Thanks in advance!
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by Intel and developed in partnership with Slashdot Media, is your hub for all
things parallel software development, from weekly thought leadership blogs to
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conversation now. http://goparallel.sourceforge.net/
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