此示例在地图上绘制各种形状和颜色的多边形。
如需了解详情，请参阅相关文档。
开始使用
您必须先配置开发环境，然后才能试用该示例代码。如需了解详情，请参阅 Maps SDK for Android 代码示例。
查看代码
Kotlin
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.polygon_demo)
fillHueBar = findViewById<SeekBar>(R.id.fillHueSeekBar).apply {
max = MAX_HUE_DEGREES
progress = MAX_HUE_DEGREES / 2
}
fillAlphaBar = findViewById<SeekBar>(R.id.fillAlphaSeekBar).apply {
max = MAX_ALPHA
progress = MAX_ALPHA / 2
}
strokeWidthBar = findViewById<SeekBar>(R.id.strokeWidthSeekBar).apply {
max = MAX_WIDTH_PX
progress = MAX_WIDTH_PX / 3
}
strokeHueBar = findViewById<SeekBar>(R.id.strokeHueSeekBar).apply {
max = MAX_HUE_DEGREES
progress = 0
}
strokeAlphaBar = findViewById<SeekBar>(R.id.strokeAlphaSeekBar).apply {
max = MAX_ALPHA
progress = MAX_ALPHA
}
strokeJointTypeSpinner = findViewById<Spinner>(R.id.strokeJointTypeSpinner).apply {
adapter = ArrayAdapter(
this@PolygonDemoActivity, android.R.layout.simple_spinner_item,
getResourceStrings(jointTypeNameResourceIds))
}
strokePatternSpinner = findViewById<Spinner>(R.id.strokePatternSpinner).apply {
adapter = ArrayAdapter(
this@PolygonDemoActivity, android.R.layout.simple_spinner_item,
getResourceStrings(patternTypeNameResourceIds))
}
clickabilityCheckbox = findViewById(R.id.toggleClickability)
val mapFragment = supportFragmentManager.findFragmentById(R.id.map) as SupportMapFragment
mapFragment.getMapAsync(this)
}
override fun onMapReady(googleMap: GoogleMap) {
// return early if the map was not initialised properly
googleMap ?: return
val fillColorArgb = Color.HSVToColor(
fillAlphaBar.progress, floatArrayOf(fillHueBar.progress.toFloat(), 1f, 1f))
val strokeColorArgb = Color.HSVToColor(
strokeAlphaBar.progress, floatArrayOf(strokeHueBar.progress.toFloat(), 1f, 1f))
with(googleMap) {
// Override the default content description on the view, for accessibility mode.
setContentDescription(getString(R.string.polygon_demo_description))
// Move the googleMap so that it is centered on the mutable polygon.
moveCamera(CameraUpdateFactory.newLatLngZoom(center, 4f))
// Create a rectangle with two rectangular holes.
mutablePolygon = addPolygon(PolygonOptions().apply {
addAll(createRectangle(center, 5.0, 5.0))
addHole(createRectangle(LatLng(-22.0, 128.0), 1.0, 1.0))
addHole(createRectangle(LatLng(-18.0, 133.0), 0.5, 1.5))
fillColor(fillColorArgb)
strokeColor(strokeColorArgb)
strokeWidth(strokeWidthBar.progress.toFloat())
clickable(clickabilityCheckbox.isChecked)
})
// Add a listener for polygon clicks that changes the clicked polygon's stroke color.
setOnPolygonClickListener { polygon ->
// Flip the red, green and blue components of the polygon's stroke color.
polygon.strokeColor = polygon.strokeColor xor 0x00ffffff
}
}
// set listeners on seekBars
arrayOf(fillHueBar, fillAlphaBar, strokeWidthBar, strokeHueBar, strokeAlphaBar).map {
it.setOnSeekBarChangeListener(this)
}
// set listeners on spinners
arrayOf(strokeJointTypeSpinner, strokePatternSpinner).map {
it.onItemSelectedListener = this
}
// set line pattern and joint type based on current spinner position
with(mutablePolygon) {
strokeJointType = getSelectedJointType(strokeJointTypeSpinner.selectedItemPosition)
strokePattern = getSelectedPattern(strokePatternSpinner.selectedItemPosition)
}
}
Java
public class PolygonDemoActivity extends AppCompatActivity
implements OnSeekBarChangeListener, OnItemSelectedListener, OnMapReadyCallback {
private static final LatLng CENTER = new LatLng(-20, 130);
private static final int MAX_WIDTH_PX = 100;
private static final int MAX_HUE_DEGREES = 360;
private static final int MAX_ALPHA = 255;
private static final int PATTERN_DASH_LENGTH_PX = 50;
private static final int PATTERN_GAP_LENGTH_PX = 10;
private static final Dot DOT = new Dot();
private static final Dash DASH = new Dash(PATTERN_DASH_LENGTH_PX);
private static final Gap GAP = new Gap(PATTERN_GAP_LENGTH_PX);
private static final List<PatternItem> PATTERN_DOTTED = Arrays.asList(DOT, GAP);
private static final List<PatternItem> PATTERN_DASHED = Arrays.asList(DASH, GAP);
private static final List<PatternItem> PATTERN_MIXED = Arrays.asList(DOT, GAP, DOT, DASH, GAP);
private Polygon mutablePolygon;
private SeekBar fillHueBar;
private SeekBar fillAlphaBar;
private SeekBar strokeWidthBar;
private SeekBar strokeHueBar;
private SeekBar strokeAlphaBar;
private Spinner strokeJointTypeSpinner;
private Spinner strokePatternSpinner;
private CheckBox clickabilityCheckbox;
// These are the options for polygon stroke joints and patterns. We use their
// string resource IDs as identifiers.
private static final int[] JOINT_TYPE_NAME_RESOURCE_IDS = {
R.string.joint_type_default, // Default
R.string.joint_type_bevel,
R.string.joint_type_round,
};
private static final int[] PATTERN_TYPE_NAME_RESOURCE_IDS = {
R.string.pattern_solid, // Default
R.string.pattern_dashed,
R.string.pattern_dotted,
R.string.pattern_mixed,
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.polygon_demo);
fillHueBar = findViewById(R.id.fillHueSeekBar);
fillHueBar.setMax(MAX_HUE_DEGREES);
fillHueBar.setProgress(MAX_HUE_DEGREES / 2);
fillAlphaBar = findViewById(R.id.fillAlphaSeekBar);
fillAlphaBar.setMax(MAX_ALPHA);
fillAlphaBar.setProgress(MAX_ALPHA / 2);
strokeWidthBar = findViewById(R.id.strokeWidthSeekBar);
strokeWidthBar.setMax(MAX_WIDTH_PX);
strokeWidthBar.setProgress(MAX_WIDTH_PX / 3);
strokeHueBar = findViewById(R.id.strokeHueSeekBar);
strokeHueBar.setMax(MAX_HUE_DEGREES);
strokeHueBar.setProgress(0);
strokeAlphaBar = findViewById(R.id.strokeAlphaSeekBar);
strokeAlphaBar.setMax(MAX_ALPHA);
strokeAlphaBar.setProgress(MAX_ALPHA);
strokeJointTypeSpinner = findViewById(R.id.strokeJointTypeSpinner);
strokeJointTypeSpinner.setAdapter(new ArrayAdapter<>(
this, android.R.layout.simple_spinner_item,
getResourceStrings(JOINT_TYPE_NAME_RESOURCE_IDS)));
strokePatternSpinner = findViewById(R.id.strokePatternSpinner);
strokePatternSpinner.setAdapter(new ArrayAdapter<>(
this, android.R.layout.simple_spinner_item,
getResourceStrings(PATTERN_TYPE_NAME_RESOURCE_IDS)));
clickabilityCheckbox = findViewById(R.id.toggleClickability);
SupportMapFragment mapFragment =
(SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap map) {
// Override the default content description on the view, for accessibility mode.
map.setContentDescription(getString(R.string.polygon_demo_description));
int fillColorArgb = Color.HSVToColor(
fillAlphaBar.getProgress(), new float[]{fillHueBar.getProgress(), 1, 1});
int strokeColorArgb = Color.HSVToColor(
strokeAlphaBar.getProgress(), new float[]{strokeHueBar.getProgress(), 1, 1});
// Create a rectangle with two rectangular holes.
mutablePolygon = map.addPolygon(new PolygonOptions()
.addAll(createRectangle(CENTER, 5, 5))
.addHole(createRectangle(new LatLng(-22, 128), 1, 1))
.addHole(createRectangle(new LatLng(-18, 133), 0.5, 1.5))
.fillColor(fillColorArgb)
.strokeColor(strokeColorArgb)
.strokeWidth(strokeWidthBar.getProgress())
.clickable(clickabilityCheckbox.isChecked()));
fillHueBar.setOnSeekBarChangeListener(this);
fillAlphaBar.setOnSeekBarChangeListener(this);
strokeWidthBar.setOnSeekBarChangeListener(this);
strokeHueBar.setOnSeekBarChangeListener(this);
strokeAlphaBar.setOnSeekBarChangeListener(this);
strokeJointTypeSpinner.setOnItemSelectedListener(this);
strokePatternSpinner.setOnItemSelectedListener(this);
mutablePolygon.setStrokeJointType(getSelectedJointType(strokeJointTypeSpinner.getSelectedItemPosition()));
mutablePolygon.setStrokePattern(getSelectedPattern(strokePatternSpinner.getSelectedItemPosition()));
// Move the map so that it is centered on the mutable polygon.
map.moveCamera(CameraUpdateFactory.newLatLngZoom(CENTER, 4));
// Add a listener for polygon clicks that changes the clicked polygon's stroke color.
map.setOnPolygonClickListener(new GoogleMap.OnPolygonClickListener() {
@Override
public void onPolygonClick(Polygon polygon) {
// Flip the red, green and blue components of the polygon's stroke color.
polygon.setStrokeColor(polygon.getStrokeColor() ^ 0x00ffffff);
}
});
}
}
克隆并运行示例
您必须拥有 Git，才能在本地运行此示例。以下命令会克隆示例应用代码库。
git clone git@github.com:googlemaps-samples/android-samples.git
将示例项目导入到 Android Studio：
- 在 Android Studio 中，依次选择 File > New > Import Project。
前往代码库的保存位置并选择 Kotlin 或 Java 的项目目录：
- Kotlin：
PATH-REPO/android-samples/ApiDemos/kotlin - Java：
PATH-REPO/android-samples/ApiDemos/java
- Kotlin：
- 选择 Open。Android Studio 会使用 Gradle 构建工具来构建您的项目。
- 在项目的
local.properties文件所在的同一目录中，创建一个空白secrets.properties文件。如需了解详情，请参阅将您的 API 密钥添加到项目中。 在
secrets.properties中添加以下字符串，并将 YOUR_API_KEY 替换为您的 API 密钥的值：MAPS_API_KEY=YOUR_API_KEY- 运行应用。