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Speeding alerts

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Note

This example is a part of the Vision SDK Examples. You can find the values for all referenced resources in the res directory. For example, see res/values/strings.xml for R.string.* references used in this example. The dependencies can be found here.The examples use View binding.See setup documention if necessary.

activity_main
github View on GitHub
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.mapbox.vision.view.VisionView
        android:id="@+id/vision_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:visualization_mode="clear" />

    <FrameLayout
        android:id="@+id/speed_alert_view"
        android:layout_width="@dimen/speed_limit_view_width"
        android:layout_height="@dimen/speed_limit_view_height"
        android:layout_gravity="end|top"
        android:layout_margin="15dp"
        android:visibility="gone">

        <ImageView
            android:id="@+id/speed_sign_view"
            android:layout_width="@dimen/speed_limit_view_width"
            android:layout_height="@dimen/speed_limit_view_height"
            android:src="@drawable/speed_limit_normal" />

        <TextView
            android:id="@+id/speed_value_view"
            android:layout_width="@dimen/speed_limit_speed_view_width"
            android:layout_height="@dimen/speed_limit_speed_view_height"
            android:layout_gravity="bottom|center_horizontal"
            android:layout_marginBottom="10dp"
            android:gravity="center"
            android:textSize="40dp"
            android:textStyle="bold"
            tools:ignore="SpUsage"
            tools:text="40" />
    </FrameLayout>

</FrameLayout>
SafetyActivity.java
github View on GitHub
package com.mapbox.vision.examples;

import android.view.View;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.TextView;

import androidx.core.content.ContextCompat;

import com.mapbox.vision.VisionManager;
import com.mapbox.vision.mobile.core.interfaces.VisionEventsListener;
import com.mapbox.vision.mobile.core.models.AuthorizationStatus;
import com.mapbox.vision.mobile.core.models.Camera;
import com.mapbox.vision.mobile.core.models.Country;
import com.mapbox.vision.mobile.core.models.FrameSegmentation;
import com.mapbox.vision.mobile.core.models.classification.FrameSignClassifications;
import com.mapbox.vision.mobile.core.models.detection.FrameDetections;
import com.mapbox.vision.mobile.core.models.position.VehicleState;
import com.mapbox.vision.mobile.core.models.road.RoadDescription;
import com.mapbox.vision.mobile.core.models.world.WorldDescription;
import com.mapbox.vision.safety.VisionSafetyManager;
import com.mapbox.vision.safety.core.VisionSafetyListener;
import com.mapbox.vision.safety.core.models.CollisionObject;
import com.mapbox.vision.safety.core.models.RoadRestrictions;
import com.mapbox.vision.view.VisionView;

import org.jetbrains.annotations.NotNull;

/**
 * Example shows how overspeed can be detected using Vision and VisionSafety SDKs combined.
 */
public class SafetyActivity extends BaseActivity {

    private float maxAllowedSpeed = -1f;
    private boolean visionManagerWasInit = false;
    private VisionView visionView;
    private FrameLayout speedAlertView;
    private TextView speedLimitValueView;
    private ImageView speedLimitSignView;

    private static class SpeedLimit {
        private int imageResId;
        private int textColorId;

        SpeedLimit(final int imageResId, final int textColorId) {
            this.imageResId = imageResId;
            this.textColorId = textColorId;
        }
    }

    private final SpeedLimit overspeeding = new SpeedLimit(R.drawable.speed_limit_overspeeding, android.R.color.white);
    private final SpeedLimit normal = new SpeedLimit(R.drawable.speed_limit_normal, android.R.color.black);

    // this listener handles events from Vision SDK
    private VisionEventsListener visionEventsListener = new VisionEventsListener() {

        @Override
        public void onAuthorizationStatusUpdated(@NotNull AuthorizationStatus authorizationStatus) {
        }

        @Override
        public void onFrameSegmentationUpdated(@NotNull FrameSegmentation frameSegmentation) {
        }

        @Override
        public void onFrameDetectionsUpdated(@NotNull FrameDetections frameDetections) {
        }

        @Override
        public void onFrameSignClassificationsUpdated(@NotNull FrameSignClassifications frameSignClassifications) {
        }

        @Override
        public void onRoadDescriptionUpdated(@NotNull RoadDescription roadDescription) {
        }

        @Override
        public void onWorldDescriptionUpdated(@NotNull WorldDescription worldDescription) {
        }

        @Override
        public void onVehicleStateUpdated(@NotNull VehicleState vehicleState) {
            // do nothing if we did not find any speed limit signs
            if (maxAllowedSpeed == -1f) return;

            // current speed of our car
            final float mySpeed = vehicleState.getSpeed();
            final SpeedLimit currentSpeedState = (mySpeed > maxAllowedSpeed && maxAllowedSpeed > 0) ? overspeeding : normal;
            // all VisionListener callbacks are executed on a background thread. Need switch to a main thread
            runOnUiThread(() -> {
                speedLimitSignView.setImageResource(currentSpeedState.imageResId);
                speedLimitValueView.setTextColor(ContextCompat.getColor(
                        SafetyActivity.this,
                        currentSpeedState.textColorId)
                );
            });
        }

        @Override
        public void onCameraUpdated(@NotNull Camera camera) {
        }

        @Override
        public void onCountryUpdated(@NotNull Country country) {
        }

        @Override
        public void onUpdateCompleted() {
        }
    };

    private VisionSafetyListener visionSafetyListener = new VisionSafetyListener() {
        @Override
        public void onCollisionsUpdated(@NotNull CollisionObject[] collisions) {
        }

        @Override
        public void onRoadRestrictionsUpdated(@NotNull RoadRestrictions roadRestrictions) {
            maxAllowedSpeed = roadRestrictions.getSpeedLimits().getCar().getMax();
            if (maxAllowedSpeed != -1f) {
                runOnUiThread(() -> {
                    // set speed limit
                    speedLimitValueView.setText(String.valueOf((int) maxAllowedSpeed));
                    // start showing alert view
                    speedAlertView.setVisibility(View.VISIBLE);
                });
            }
        }
    };

    @Override
    protected void initViews() {
        setContentView(R.layout.activity_main);
        visionView = findViewById(R.id.vision_view);
        speedAlertView = findViewById(R.id.speed_alert_view);
        speedLimitValueView = findViewById(R.id.speed_value_view);
        speedLimitSignView = findViewById(R.id.speed_sign_view);
    }

    @Override
    protected void onPermissionsGranted() {
        startVisionManager();
    }

    @Override
    protected void onStart() {
        super.onStart();
        startVisionManager();
    }

    @Override
    protected void onStop() {
        super.onStop();
        stopVisionManager();
    }

    @Override
    protected void onResume() {
        super.onResume();
        visionView.onResume();
    }

    @Override
    protected void onPause() {
        super.onPause();
        visionView.onPause();
    }

    private void startVisionManager() {
        if (allPermissionsGranted() && !visionManagerWasInit) {
            VisionManager.create();
            visionView.setVisionManager(VisionManager.INSTANCE);
            VisionManager.start();
            VisionManager.setVisionEventsListener(visionEventsListener);

            VisionSafetyManager.create(VisionManager.INSTANCE);
            VisionSafetyManager.setVisionSafetyListener(visionSafetyListener);

            visionManagerWasInit = true;
        }
    }

    private void stopVisionManager() {
        if (visionManagerWasInit) {
            VisionSafetyManager.destroy();

            VisionManager.stop();
            VisionManager.destroy();

            visionManagerWasInit = false;
        }
    }
}
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