Java tutorial
/* * Copyright (C) 2012 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.cyrilmottier.android.polaris2demo; import com.cyrilmottier.polaris2.maps.CameraUpdateFactory; import com.cyrilmottier.polaris2.maps.GoogleMap; import com.cyrilmottier.polaris2.maps.SupportMapFragment; import com.cyrilmottier.polaris2.maps.model.LatLng; import com.cyrilmottier.polaris2.maps.model.Polygon; import com.cyrilmottier.polaris2.maps.model.PolygonOptions; import android.graphics.Color; import android.os.Bundle; import android.support.v4.app.FragmentActivity; import android.widget.SeekBar; import android.widget.SeekBar.OnSeekBarChangeListener; import java.util.Arrays; import java.util.Collections; import java.util.List; /** * This shows how to draw polygons on a map. */ public class PolygonDemoActivity extends FragmentActivity implements OnSeekBarChangeListener { private static final LatLng SYDNEY = new LatLng(-33.87365, 151.20689); private static final int WIDTH_MAX = 50; private static final int HUE_MAX = 360; private static final int ALPHA_MAX = 255; private GoogleMap mMap; private Polygon mMutablePolygon; private SeekBar mColorBar; private SeekBar mAlphaBar; private SeekBar mWidthBar; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.polygon_demo); mColorBar = (SeekBar) findViewById(R.id.hueSeekBar); mColorBar.setMax(HUE_MAX); mColorBar.setProgress(0); mAlphaBar = (SeekBar) findViewById(R.id.alphaSeekBar); mAlphaBar.setMax(ALPHA_MAX); mAlphaBar.setProgress(127); mWidthBar = (SeekBar) findViewById(R.id.widthSeekBar); mWidthBar.setMax(WIDTH_MAX); mWidthBar.setProgress(10); setUpMapIfNeeded(); } @Override protected void onResume() { super.onResume(); setUpMapIfNeeded(); } private void setUpMapIfNeeded() { // Do a null check to confirm that we have not already instantiated the map. if (mMap == null) { // Try to obtain the map wrap the SupportMapFragment. mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getPolarisMap(); // Check if we were successful in obtaining the map. if (mMap != null) { setUpMap(); } } } private void setUpMap() { // Create a rectangle with two rectangular holes. mMap.addPolygon(new PolygonOptions().addAll(createCWRectangle(new LatLng(-20, 130), 5, 5)) .addHole(createCWRectangle(new LatLng(-22, 128), 1, 1)) .addHole(createCWRectangle(new LatLng(-18, 133), 0.5, 1.5)).fillColor(Color.CYAN) .strokeColor(Color.BLUE).strokeWidth(5)); // Create an ellipse centered at Sydney. PolygonOptions options = new PolygonOptions(); int numPoints = 400; float semiHorizontalAxis = 10f; float semiVerticalAxis = 5f; double phase = 2 * Math.PI / numPoints; for (int i = 0; i <= numPoints; i++) { options.add(new LatLng(SYDNEY.latitude + semiVerticalAxis * Math.sin(i * phase), SYDNEY.longitude + semiHorizontalAxis * Math.cos(i * phase))); } int fillColor = Color.HSVToColor(mAlphaBar.getProgress(), new float[] { mColorBar.getProgress(), 1, 1 }); mMutablePolygon = mMap.addPolygon( options.strokeWidth(mWidthBar.getProgress()).strokeColor(Color.BLACK).fillColor(fillColor)); mColorBar.setOnSeekBarChangeListener(this); mAlphaBar.setOnSeekBarChangeListener(this); mWidthBar.setOnSeekBarChangeListener(this); // Move the map so that it is centered on the mutable polygon. mMap.moveCamera(CameraUpdateFactory.newLatLng(SYDNEY)); } /** * Creates a List of LatLngs that form a rectangle with the given dimensions. */ private List<LatLng> createRectangle(LatLng center, double halfWidth, double halfHeight) { // Note that the ordering of the points is counterclockwise (as long as the halfWidth and // halfHeight are less than 90). return Arrays.asList(new LatLng(center.latitude - halfHeight, center.longitude - halfWidth), new LatLng(center.latitude - halfHeight, center.longitude + halfWidth), new LatLng(center.latitude + halfHeight, center.longitude + halfWidth), new LatLng(center.latitude + halfHeight, center.longitude - halfWidth), new LatLng(center.latitude - halfHeight, center.longitude - halfWidth)); } private List<LatLng> createCWRectangle(LatLng center, double halfWidth, double halfHeight) { List<LatLng> rect = createRectangle(center, halfWidth, halfHeight); Collections.reverse(rect); return rect; } @Override public void onStopTrackingTouch(SeekBar seekBar) { // Don't do anything here. } @Override public void onStartTrackingTouch(SeekBar seekBar) { // Don't do anything here. } @Override public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { if (mMutablePolygon == null) { return; } if (seekBar == mColorBar) { mMutablePolygon.setFillColor( Color.HSVToColor(Color.alpha(mMutablePolygon.getFillColor()), new float[] { progress, 1, 1 })); } else if (seekBar == mAlphaBar) { int prevColor = mMutablePolygon.getFillColor(); mMutablePolygon.setFillColor( Color.argb(progress, Color.red(prevColor), Color.green(prevColor), Color.blue(prevColor))); } else if (seekBar == mWidthBar) { mMutablePolygon.setStrokeWidth(progress); } } }