I have a problem with mapview and Overlay.
I must to draw a circle on the map everytime that change GPS position.
I used the method draw in my overlay class that extend overlay.
The problem is that I must draw these circles with transparency, but when the circles overlap each other in the intersection point the color it's different because there is a sum of alpha.
How I can fix it?
This is my overlay class:
public class ImpactOverlay extends Overlay {
private static int CIRCLERADIUS = 0;
private GeoPoint geopoint;
private int myCircleRadius;
Point point = new Point();
Paint circle = new Paint(Paint.ANTI_ALIAS_FLAG);
private long systemTime= -1 ;
public ImpactOverlay(GeoPoint point, int myRadius) {
geopoint = point;
CIRCLERADIUS = myRadius; // assegna raggio del cerchio
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// Transfrom geoposition to Point on canvas
Projection projection = mapView.getProjection();
projection.toPixels(geopoint, point);
// the circle to mark the spot
circle.setColor(Color.parseColor("#88ff0000"));
circle.setAlpha(122); // trasparenza
myCircleRadius = metersToRadius(CIRCLERADIUS, mapView,
(double) geopoint.getLatitudeE6() / 1000000);
canvas.drawCircle(point.x, point.y, myCircleRadius, circle);
}
public static int metersToRadius(float meters, MapView map, double latitude) {
return (int) (map.getProjection().metersToEquatorPixels(meters) * (1 / Math
.cos(Math.toRadians(latitude))));
}
#Override
/* Implementa il doppio tap per eseguire zoom sulla mappa */
public boolean onTouchEvent(MotionEvent event, MapView mapView) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
if ((System.currentTimeMillis() - systemTime) < 250) {
mapView.getController().zoomIn();
}
systemTime = System.currentTimeMillis();
break;
}
return false;
}
}
CircleOptions circle = new CircleOptions();
circle.center(new LatLng(latitude, longitude))
.radius(1500)//in meters
.strokeColor(Color.BLUE)//border color
.strokeWidth(3.0f)//border width
.fillColor(0x200000ff);//inside circle
googleMap.addCircle(circle);//GoogleMap googleMap(initialize accordingly)
Well one possibility is to clip the area away which is intersecting the second circle like that, pseudo code:
canvas.clipPath(circle2.toPath())
canvas.draw(circle1)
canvas.removeClip()
canvas.draw(circle2)
You need to take account of the intersection when you clip, something like this:
.
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
Paint paint = new Paint();
paint.setColor(Color.parseColor("#88ff0000"));
paint.setAlpha(16); // quite transparent
Point point = new Point();
Point point2 = new Point();
float radius = 50.0f;
Projection projection = mapView.getProjection();
projection.toPixels(mGpt, point); // 1st GeoPoint
projection.toPixels(mGpt2, point2); // 2nd GeoPoint
Path path1 = new Path();
Path path2 = new Path();
path1.addCircle(point.x, point.y, radius, Direction.CW); // 1st circle
path2.addCircle(point2.x, point2.y, radius, Direction.CW); // 2nd circle
canvas.save(); // save canvas without the clip region
canvas.clipPath(path2, Region.Op.DIFFERENCE); // clip the region
// to the whole view less where circle2 will be when it's drawn
canvas.drawPath(path1, paint); // draw 1st circle minus where it overlaps
canvas.restore(); // clear the clip region
canvas.drawPath(path2, paint); // draw 2nd circle (unclipped)
return false;
}
should work
You don't need to know how many shapes are there beforehand. If you use separate overlays you could just easily draw each and add the corresponding area to the clipping area.
Full code follows:
import java.util.List;
import android.graphics.*;
import android.graphics.Path.Direction;
import android.graphics.Region.Op;
import android.os.Bundle;
import android.view.MotionEvent;
import com.google.android.maps.*;
public class CircleTest extends MapActivity {
private MapView m_map;
#Override
public void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
m_map = (MapView) findViewById(R.id.mapview);
m_map.displayZoomControls(true);
m_map.setBuiltInZoomControls(true);
}
#Override
protected void onStart() {
super.onStart();
// m_map.getOverlays().add(new ); // some other overlays
m_map.getOverlays().add(new ImpactGeneratorOverlay());
// the impact areas are being inserted between these two, see ImpactGeneratorOverlay
m_map.getOverlays().add(new ImpactClipRestoreOverlay());
}
/**
* Restore clipping area to the saved one.
*/
public static class ImpactClipRestoreOverlay extends Overlay {
#Override
public void draw(final Canvas canvas, final MapView mapView, final boolean shadow) {
super.draw(canvas, mapView, shadow);
canvas.restore();
}
}
/**
* Handles events, on touch down it adds a new Impact area to the map,
* just before the ClipRestore overlay (assume it's the last, if not store position, and insert before).
*/
public static class ImpactGeneratorOverlay extends Overlay {
#Override
public void draw(final Canvas canvas, final MapView mapView, final boolean shadow) {
super.draw(canvas, mapView, shadow);
canvas.save();
}
#Override
public boolean onTouchEvent(final MotionEvent e, final MapView mapView) {
switch (e.getActionMasked()) {
case MotionEvent.ACTION_DOWN:
GeoPoint point = mapView.getProjection().fromPixels((int) e.getX(), (int) e.getY());
List<Overlay> overlays = mapView.getOverlays();
overlays.add(overlays.size() - 1, new ImpactOverlay(point, 1000));
break;
}
return super.onTouchEvent(e, mapView);
}
}
/**
* Draw impact and remove the current shape path from the drawable area.
*/
public static class ImpactOverlay extends Overlay {
// shape parameters
private final GeoPoint circleCenter;
private final int circleRadius;
// drawing cache
private final Point circleDrawCenter = new Point();
private final Paint circlePaint = new Paint();
public ImpactOverlay(final GeoPoint circleCenter, final int circleRadius) {
this.circleCenter = circleCenter;
this.circleRadius = circleRadius;
circlePaint.setAntiAlias(true);
circlePaint.setColor(Color.argb(64, 255, 0, 0));
}
#Override
public void draw(final Canvas canvas, final MapView mapView, final boolean shadow) {
// Transfrom geoposition to Point on canvas
Projection projection = mapView.getProjection();
projection.toPixels(circleCenter, circleDrawCenter);
// the circle to mark the spot
float circleDrawRadius = ImpactOverlay.metersToRadius(mapView, circleRadius, circleCenter.getLatitudeE6() / 1e6f);
// create circle from path
Path path = new Path();
path.addCircle(circleDrawCenter.x, circleDrawCenter.y, circleDrawRadius, Direction.CW);
// draw circle
canvas.drawPath(path, circlePaint);
// remove circle from further posibble drawing areas
canvas.clipPath(path, Op.DIFFERENCE);
}
public static float metersToRadius(final MapView map, final float meters, final float latitude) {
return (float) (map.getProjection().metersToEquatorPixels(meters) * (1 / Math.cos(Math.toRadians(latitude))));
}
}
#Override
protected boolean isRouteDisplayed() {
return false;
}
}
This contains a fix for clipping unwanted layers, say the first one, but this can be avoided if you just gather all the circles in one overlay and draw them in one draw method.
The key is to draw and set clipping (even if they exist in different overlays, not advised!):
canvas.save();
canvas.drawPath(path1, paint);
canvas.clipPath(path1, Op.DIFFERENCE);
canvas.drawPath(path2, paint); // do not draw over path1
canvas.clipPath(path2, Op.DIFFERENCE);
canvas.drawPath(path3, paint); // do not draw over path1 + path2
canvas.clipPath(path3, Op.DIFFERENCE);
// do not draw over path1 + path2 + path3
canvas.restore();
canvas.drawPath(path4, paint); // draw over anything
Related
I have made one polygon over Google map v2 and now on that polygon I want to add one grid as shown in Reference Image and that grid should have to re-sizable and portions of grid should be selectable.
I don't have any idea about this so please help on this.
I am trying this so far but still don't have any result.
All your help is appreciated.
Reference Image:
Not sure about Google Maps, but with osmdroid you should use osmbonuspack and implement a custom Polygon:
public class GridPolygon extends Polygon {
private BitmapShader bitmapShader;
private IGeoPoint lastCenterGeoPoint;
private int xOffset = 0;
private int yOffset = 0;
public GridPolygon(Context ctx) {
super(ctx);
}
public void setPatternBMP(#NonNull final Bitmap patternBMP) {
bitmapShader = new BitmapShader(patternBMP, Shader.TileMode.REPEAT, Shader.TileMode.REPEAT);
mFillPaint.setShader(bitmapShader);
}
protected void recalculateMatrix(#NonNull final MapView mapView) {
//final int mapSize = TileSystem.MapSize(mapView.getZoomLevel());
final Projection projection = mapView.getProjection();
final IGeoPoint geoPoint = mapView.getMapCenter();
if (lastCenterGeoPoint == null) lastCenterGeoPoint = geoPoint;
final Point point = projection.toPixels(geoPoint, null);
final Point lastCenterPoint = projection.toPixels(lastCenterGeoPoint, null);
xOffset += lastCenterPoint.x - point.x;
yOffset += lastCenterPoint.y - point.y;
xOffset %= 100; // 100 is pixel size of shader image
yOffset %= 100;
final Matrix matrix = new Matrix();
matrix.reset();
matrix.setScale(1,1);
matrix.preTranslate(xOffset, yOffset);
//matrix.setTranslate(xOffset, yOffset);
bitmapShader.setLocalMatrix(matrix);
mFillPaint.setShader(bitmapShader);
lastCenterGeoPoint = geoPoint;
}
#Override
protected void draw(Canvas canvas, MapView mapView, boolean shadow) {
recalculateMatrix(mapView);
super.draw(canvas, mapView, shadow);
}
}
Full source code.
In my app Draw paint in free hand on Map view but searching lot of information finally got from rectangle shape draw on mapview but i want in place of rectangle draw free hand like zigzag how to change my code Any help please..
MapOverlay.java
public class MapOverlay extends Overlay {
private float x1,y1,x2,y2;
private GeoPoint p1=null,p2=null;
private MapExampleActivity mv = null;
private Paint paint = new Paint();
private Path path = new Path();
private boolean isUp = false;
//constructor receiving the initial point
public MapOverlay(MapExampleActivity mapV,float x,float y){
paint.setStrokeWidth(2.0f);
x1 = x;
y1 = y;
mv = mapV;
p1 = mapV.getMapView().getProjection().fromPixels((int)x1,(int)y1);
}
//override draw method to add our custom drawings
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) {
if(p1 != null && p2 != null){
//get the 2 geopoints defining the area and transform them to pixels
//this way if we move or zoom the map rectangle will follow accordingly
Point screenPts1 = new Point();
mapView.getProjection().toPixels(p1, screenPts1);
Point screenPts2 = new Point();
mapView.getProjection().toPixels(p2, screenPts2);
//draw inner rectangle
paint.setColor(Color.BLUE);
// paint.setStyle(Style.FILL);
canvas.drawPath(path, paint);
canvas.drawRect(screenPts1.x, screenPts1.y, screenPts2.x, screenPts2.y, paint);
//draw outline rectangle
// paint.setColor(Color.YELLOW);
paint.setStyle(Style.STROKE);
// canvas.drawRect(screenPts1.x, screenPts1.y, screenPts2.x, screenPts2.y, paint);
canvas.drawPath(path, paint);
}
return true;
}
#Override
public boolean onTouchEvent(MotionEvent e, MapView mapView) {
if(mv.isEditMode() && !isUp){
if(e.getAction() == MotionEvent.ACTION_DOWN){
x1 = y1 = 0;
x1 = e.getX();
y1 = e.getY();
p1 = mapView.getProjection().fromPixels((int)x1,(int)y1);
}
//here we constantly change geopoint p2 as we move out finger
if(e.getAction() == MotionEvent.ACTION_MOVE){
x2 = e.getX();
y2 = e.getY();
p2 = mapView.getProjection().fromPixels((int)x2,(int)y2);
}
//---when user lifts his finger---
if (e.getAction() == MotionEvent.ACTION_UP) {
isUp = true;
}
return true;
}
return false;
}
}
using this i able to draw like this rectangle shapes and draw up to again you click the toggle button(possible to draw multiple times)
i want draw lines instead of rectangle like below image(draw multiple times).
finally i found this link this link provide rectangle shape draw http://n3vrax.wordpress.com/2011/08/13/drawing-overlays-on-android-map-view/
just change rectangle to free draw any idea please....
You can free hand draw a line using the code bellow:
Code
public class HandDrawOverlay extends Overlay {
private boolean editMode = false;
private boolean isTouched = false;
private Paint paint = new Paint();
private Point screenPt1 = new Point();
private Point screenPt2 = new Point();
private ArrayList<GeoPoint> points = null;
public HandDrawOverlay(){
paint.setStrokeWidth(2.0f);
paint.setStyle(Style.STROKE);
paint.setColor(Color.BLUE);
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
if(points != null && points.size() > 1){
mapView.getProjection().toPixels(points.get(0), screenPt1);
for(int i=1; i<points.size();i++){
mapView.getProjection().toPixels(points.get(i), screenPt2);
canvas.drawLine(screenPt1.x, screenPt1.y, screenPt2.x, screenPt2.y, paint);
screenPt1.set(screenPt2.x, screenPt2.y);
}
}
}
#Override
public boolean onTouchEvent(MotionEvent e, MapView mapView) {
if(editMode){
int x = (int)e.getX();
int y = (int)e.getY();
GeoPoint geoP = mapView.getProjection().fromPixels(x,y);
switch (e.getAction()) {
case MotionEvent.ACTION_DOWN:
isTouched = true;
points = new ArrayList<GeoPoint>();
points.add(geoP);
break;
case MotionEvent.ACTION_MOVE:
if(isTouched)
points.add(geoP);
break;
case MotionEvent.ACTION_UP:
if(isTouched)
points.add(geoP);
isTouched = false;
break;
}
mapView.invalidate();
return true;
}
return false;
}
/**
* #return the editMode
*/
public boolean isEditMode() {
return editMode;
}
/**
* #param editMode the editMode to set
*/
public void setEditMode(boolean editMode) {
this.editMode = editMode;
}
}
to use
HandDrawOverlay handDrawOverlay;
handDrawOverlay = new HandDrawOverlay();
mapView.getOverlays().add(handDrawOverlay);
//Set edit mode to true to start drwaing
handDrawOverlay.setEditMode(true);
//Set edit mode to true to stop drwaing
handDrawOverlay.setEditMode(false);
Note
This is a full functioning example to help you starting. However, you should optimize the code to make it more efficient (i.e. using Path to store the drawing path in onDraw(), reducing the number of points recorded in onTouch(), etc.).
Enjoy it.
Hi I am beginner in android development. I am developing a paint like application. I have already drawn some points on the canvas. Now I want to draw line between these points through fingure.I dont konw how i can do this. I am not using google maps.
package com.example.point;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PointF;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
public class DrawView extends View implements OnTouchListener {
private static final String TAG = "DrawView";
List<Point> points = new ArrayList<Point>();
List<Point> points1 = new ArrayList<Point>();
List<Point> points2 = new ArrayList<Point>();
Paint paint = new Paint();
PointF firstpoint=new PointF(100,100);
PointF secondpoint=new PointF(200,200);
Path path=new Path();
public DrawView(Context context) {
super(context);
setFocusable(true);
setFocusableInTouchMode(true);
this.setOnTouchListener(this);
paint.setColor(Color.BLACK);
paint.setAntiAlias(true);
}
#Override
public void onDraw(Canvas canvas) {
paint.setStrokeWidth(3);
canvas.drawPoint(100, 100, paint);
canvas.drawPoint(200, 200, paint);
canvas.drawPoint(200, 400, paint);
Point p=new Point();
Point p1=new Point();
//p1=points.get(1);
for(int i=points.size()-2;i<points.size();i++)
{
p=points.get(i);
//if(p1.x==100 && p1.y==100)
//canvas.drawLine(100, 100, p.x, p.y, paint);
// path.moveTo(100, 100);
//path.lineTo(200, 200);
//canvas.drawPath(path, paint);
}
}
public boolean onTouch(View view, MotionEvent event) {
/*if(event.getAction()==MotionEvent.ACTION_MOVE)
{
Point point1 = new Point();
point1.x = event.getX();
point1.y = event.getY();
points.add(point1);
invalidate();
Log.d(TAG, "point: " + point1);
}*/
//if(event.getX()==100 && event.getY()==100)
//{
if(event.getAction()==MotionEvent.ACTION_MOVE)
{
Point point1 = new Point();
point1.x = event.getX();
point1.y = event.getY();
points.add(point1);
invalidate();
Log.d(TAG, "point: " + point1);
//}
}
//return false;
return true;
/*switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
Point point = new Point();
point.x = event.getX();
point.y = event.getY();
points.add(point);
invalidate();
Log.d(TAG, "point: " + point);
return true;
case MotionEvent.ACTION_MOVE:
Point point1 = new Point();
point1.x = event.getX();
point1.y = event.getY();
points1.add(point1);
invalidate();
Log.d(TAG, "point: " + point1);
return true;
case MotionEvent.ACTION_UP:
Point point2 = new Point();
point2.x = event.getX();
point2.y = event.getY();
points2.add(point2);
invalidate();
Log.d(TAG, "point: " + point2);
return true;
}
return false;
// return true;*/
}
}
class Point {
float x, y;
#Override
public String toString() {
return x + ", " + y;
}
}
I want to just draw a straight line between these points with fingure. If my fingure move far from that particular point after that i move back my fingure than the line drawn will be erased. i.e. the line only drawn between these particular points.
Just a heads up here in SO, It is usually best if you'd come and ask here only after you've tried something and didn't succeed. this way you want get comments such as "What have you tried..?" and stuff like that.
Regarding your question. http://developer.android.com/reference/android/graphics/Canvas.html is a good place to start. the Android documentation is very helpful.
As you can see you have a drawLine() method. which should do what you asked.
Good luck!
public class HelloGoogleMaps extends MapActivity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
MapController mMapController;
MapView mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
mMapController = mapView.getController();
mMapController.setZoom(18);
// Two points in Mexico about 1km apart
GeoPoint point1 = new GeoPoint(19240000,-99120000);
GeoPoint point2 = new GeoPoint(19241000,-99121000);
mMapController.setCenter(point2);
// Pass the geopoints to the overlay class
MapOverlay mapOvlay = new MapOverlay(point1, point2);
mapView.getOverlays().add(mapOvlay);
}
public class MapOverlay extends com.google.android.maps.Overlay {
private GeoPoint mGpt1;
private GeoPoint mGpt2;
protected MapOverlay(GeoPoint gp1, GeoPoint gp2 ) {
mGpt1 = gp1;
mGpt2 = gp2;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
super.draw(canvas, mapView, shadow);
Paint paint;
paint = new Paint();
paint.setColor(Color.RED);
paint.setAntiAlias(true);
paint.setStyle(Style.STROKE);
paint.setStrokeWidth(2);
Point pt1 = new Point();
Point pt2 = new Point();
Projection projection = mapView.getProjection();
projection.toPixels(mGpt1, pt1);
projection.toPixels(mGpt2, pt2);
canvas.drawLine(pt1.x, pt1.y, pt2.x, pt2.y, paint);
return true;
}
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
}
Its Runnnig Code In My Apps..All The Best
Is your canvas sitting inside a View? If so, here is a starting point assuming you are asking about using finger movements to draw lines between points...
Look up the following method for help:
public boolean onTouchEvent(MotionEvent event)
to detect finger movements. You will need to distinguish between the type of motion action that has just happened, and the motion action "index". Then if the motion is a moving motion (e.g. fingers moving between points), then you can call drawPath or drawLine to draw your lines.
I am trying to draw a line on my maps project, but can't get the line to draw. Where and how do I declare the overlay? I've tried various methods, but can't get it to work. ie, code just displays errors in Eclipse. What I am NOT trying to do is draw a route from A to B, but rather draw the route as I am moving.
// Creating a MapView
public class Gpstrack extends MapActivity {
private MapView map;
private MapController controller;
private Projection projection;
ArrayList<GeoPoint> geoPointsArray = new ArrayList<GeoPoint>();
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
initMapView();
initMyLocation();
TabHost.TabSpec spec;
TabHost th = (TabHost)findViewById(R.id.tabhost);
th.setup();
spec = th.newTabSpec("tag1");
spec.setContent(R.id.map_Tab);
spec.setIndicator("Map");
th.addTab(spec);
spec = th.newTabSpec("tag2");
spec.setContent(R.id.log_Tab);
spec.setIndicator("Log");
th.addTab(spec);
spec = th.newTabSpec("tag3");
spec.setContent(R.id.details_Tab);
spec.setIndicator("Details");
th.addTab(spec);
spec = th.newTabSpec("tag4");
spec.setContent(R.id.student_Tab);
spec.setIndicator("Student Info");
th.addTab(spec);
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
//Map and Controls
private void initMapView() {
map = (MapView) findViewById(R.id.mvMain);
controller = map.getController();
map.setSatellite(true);
//map.setStreetView(true);
map.setBuiltInZoomControls(true);
}
//Creates an Overlay that marks current position
private void initMyLocation() {
final MyLocationOverlay overlay = new MyLocationOverlay(this, map);
overlay.enableMyLocation();
overlay.enableCompass();
overlay.runOnFirstFix(new Runnable() {
public void run() {
controller.setZoom(17);
controller.animateTo(overlay.getMyLocation());
map.getOverlays().add(overlay);
}
});
}
//Experiment
class MyOverlay extends Overlay {
public void draw(Canvas canvas, MapView mapv, boolean shadow) {
super.draw(canvas, mapv, shadow);
Projection projection = mapv.getProjection();
Path p = new Path();
for (int i = 0; i < geoPointsArray.size(); i++) {
if (i == geoPointsArray.size() -1) {
break;
}
Point from = new Point();
Point to = new Point();
projection.toPixels(geoPointsArray.get(i), from);
projection.toPixels(geoPointsArray.get(i + 1), to);
p.moveTo(from.x, from.y);
p.lineTo(to.x, to.y);
}
Paint mPaint = new Paint();
mPaint.setStyle(Style.STROKE);
mPaint.setColor(Color.GREEN);
mPaint.setAntiAlias(true);
mPaint.setStrokeWidth(5);
canvas.drawPath(p, mPaint);
mapv.invalidate();
super.draw(canvas, mapv, shadow);
}
}
}
Have you tried with this demo to implement the Google Map Overlay?
In you overlay class you can draw line like this
public class MapOverlay extends com.google.android.maps.Overlay
{
Canvas canvas;
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when)
{
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
this.canvas=canvas;
Point screenpoint = new Point();
mapView.getProjection().toPixels(p, screenpoint);
Bitmap bmp = BitmapFactory.decodeResource(
getResources(), R.drawable.pushpin);
canvas.drawBitmap(bmp, canvas.getWidth()/4,
canvas.getHeight()/4, null);
Paint paint = new Paint();
paint.setColor(Color.BLACK);
canvas.drawLine(canvas.getWidth()/4, canvas.getHeight()/4,
canvas.getWidth()/2, canvas.getHeight()/2, paint);
return true;
}
return true;
}
}
the draw line function is like
public void drawLine (float startX, float startY,
float stopX, float stopY, Paint paint)
Since: API Level 1 Draw a line segment with the specified start and stop x,y coordinates, using the specified paint.
Parameters
startX The x-coordinate of the start point of the line
startY The y-coordinate of the start point of the line
paint The paint used to draw the line
and you can reffer this quetion if you want to draw a path
J2ME/Android/BlackBerry - driving directions, route between two locations
I think you should try this link Drawing a line/path on Google Maps
and this one J2ME/Android/BlackBerry - driving directions, route between two locations .I think this should help you.
I am trying to draw a circle around my position. I am not sure what i am doing wrong, but the circle s not showing:
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
Projection projection = mapView.getProjection();
if (shadow == false && location != null) {
// Get the current location
Double latitude = location.getLatitude() * 1E6;
Double longitude = location.getLongitude() * 1E6;
GeoPoint geoPoint = new GeoPoint(latitude.intValue(),
longitude.intValue());
int radius = metersToRadius(100, mapView, latitude);
// Convert the location to screen pixels
Point point = new Point();
projection.toPixels(geoPoint, point);
// Setup the paint
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setStrokeWidth(2.0f);
paint.setColor(0xff6666ff);
paint.setStyle(Style.STROKE);
canvas.drawCircle(point.x, point.y, radius, paint);
paint.setColor(0x186666ff);
paint.setStyle(Style.FILL);
canvas.drawCircle(point.x, point.y, radius, paint);
}
super.draw(canvas, mapView, shadow);
}
Edit: Just to make it clear i am going to post my classes:
CustomItemizedOverlay
public class CustomItemizedOverlay extends ItemizedOverlay<OverlayItem> {
protected final List<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
protected final Context mContext;
public CustomItemizedOverlay(Drawable defaultMarker, Context context) {
super(boundCenterBottom(defaultMarker));
this.mContext = context;
}
public void addOverlay(OverlayItem overlay) {
mOverlays.add(overlay);
populate();
}
#Override
protected OverlayItem createItem(int i) {
// TODO Auto-generated method stub
return mOverlays.get(i);
}
public void removeOverlay(OverlayItem overlay) {
mOverlays.remove(overlay);
populate();
}
public void clear() {
mOverlays.clear();
populate();
}
#Override
public int size() {
// TODO Auto-generated method stub
return mOverlays.size();
}
#Override
protected boolean onTap(int i) {
OverlayItem itemClicked = this.mOverlays.get(i);
AlertDialog.Builder builder = new AlertDialog.Builder(this.mContext);
builder.setTitle(itemClicked.getTitle());
builder.setMessage(itemClicked.getSnippet());
builder.setCancelable(true);
AlertDialog alert = builder.create();
alert.show();
return true;
}
And PcCustomizedOverlay
public class PcCustomItemizedOverlay extends CustomItemizedOverlay {
public static int metersToRadius(float meters, MapView map, double latitude) {
return (int) (map.getProjection().metersToEquatorPixels(meters) * (1 / Math
.cos(Math.toRadians(latitude))));
}
private Location location;
public PcCustomItemizedOverlay(Drawable defaultMarker, Context context) {
super(defaultMarker, context);
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
Projection projection = mapView.getProjection();
if (shadow == false && location != null) {
// Get the current location
Double latitude = location.getLatitude() * 1E6;
Double longitude = location.getLongitude() * 1E6;
GeoPoint geoPoint = new GeoPoint(latitude.intValue(),
longitude.intValue());
int radius = metersToRadius(40, mapView, latitude);
// Convert the location to screen pixels
Point point = new Point();
projection.toPixels(geoPoint, point);
// Setup the paint
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setStrokeWidth(2.0f);
paint.setColor(0xff6666ff);
paint.setStyle(Style.STROKE);
canvas.drawCircle(point.x, point.y, radius, paint);
paint.setColor(0x186666ff);
paint.setStyle(Style.FILL);
canvas.drawCircle(point.x, point.y, radius, paint);
}
super.draw(canvas, mapView, shadow);
}
public Location getLocation() {
return location;
}
public void setLocation(Location location) {
this.location = location;
}
}
Does anyone know where is the problem?
Thank you very much
try this code
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mapView = (MapView) findViewById(R.id.mapview);
MapController mc = mapView.getController();
MyLocationOverlay myLocationOverlay = new MyLocationOverlay(MainMap.this, mapView);
mapView.getOverlays().add(myLocationOverlay);
mc.animateTo( new GeoPoint(lat, lng));
mc.setZoom(15);
mapView.invalidate();
}
Dont forget to add overlay.enableMyLocation(); in onresume() and overlay.disableMyLocation(); in on pause
Instead of the above code if you want to draw circle around you point you can use following sample code:
Point screenPnts =new Point();
GeoPoint curr_geopoint = new GeoPoint((int)(location.getLatitude()*1E6),(int)(location.getLongitude()*1E6));
mapview.getProjection().toPixels(curr_geopoint, screenPnts);
canvas.drawCircle(screenPnts.x, screenPnts.y, 15, paint);
do some trial & error to get that circle around the point by manipulating screenPnts.x and screenPnts.y values. here paint is the object of Paint class to give the color to the circle
I think problem in your void draw.
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
super.draw(canvas, mapView, shadow);
Projection projection = mapView.getProjection();
if (shadow == false && location != null) {
// Get the current location
Double latitude = location.getLatitude() * 1E6;
Double longitude = location.getLongitude() * 1E6;
GeoPoint geoPoint = new GeoPoint(latitude.intValue(),
longitude.intValue());
int radius = metersToRadius(100, mapView, latitude);
// Convert the location to screen pixels
Point point = new Point();
projection.toPixels(geoPoint, point);
// Setup the paint
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setStrokeWidth(2.0f);
paint.setColor(0xff6666ff);
paint.setStyle(Style.STROKE);
canvas.drawCircle(point.x, point.y, radius, paint);
paint.setColor(0x186666ff);
paint.setStyle(Style.FILL);
canvas.drawCircle(point.x, point.y, radius, paint);
}
}
Look here also for put image over your map.drawing image as mapoverlay
I've had similar problem.
Solved it with overriding boolean draw instead of void one in inner class that extended Overlay.
It would look like this:
//inner class MapOverlay
class MapOverlay extends com.google.android.maps.Overlay
{
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when)
{
super.draw(canvas, mapView, shadow);
Projection projection = mapView.getProjection();
//the rest of your code here................
super.draw(canvas,mapView,shadow);
return true;
}
}
Construct your circle with
MapOverlay mapOverlayCircle = new MapOverlay();
and add it to your Overlays in your mapView. that's it.