Android 定位功能使用状态监听

前言

由于做认证需要，提出增加对定位状态使用监听； 使用时显示定位icon，未使用时隐藏定位icon

使用

功能参考Android10 源码，如果需要查看源码可以在结尾查看

import android.app.AppOpsManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.location.LocationManager;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.os.UserHandle;
import android.util.Log;

import androidx.annotation.VisibleForTesting;
import java.util.ArrayList;
import java.util.List;


public class LocationListenerHelper extends BroadcastReceiver implements LocationController {
    private static final String TAG = "LocationListenerHelper";
    private static volatile LocationListenerHelper INSTANCE;
    private static final int[] mHighPowerRequestAppOpArray
            = new int[]{AppOpsManager.OP_MONITOR_HIGH_POWER_LOCATION};
    private Context context;

    private HandlerThread mHandlerThread = new HandlerThread("ActiveLocationHandlerThread");

    private AppOpsManager mAppOpsManager;

    private boolean mAreActiveLocationRequests;

    private final ArrayList<LocationChangeCallback> mSettingsChangeCallbacks =
            new ArrayList<LocationChangeCallback>();
    private final H mHandler = new H();

    public static LocationListenerHelper getInstance(Context context) {
        if (INSTANCE == null) {
            synchronized (LocationListenerHelper.class) {
                if (INSTANCE == null) {
                    INSTANCE = new LocationListenerHelper(context);
                }
            }
        }
        return INSTANCE;
    }

    private LocationListenerHelper(Context context) {
        this.context = context.getApplicationContext();

        mHandlerThread.start();
        IntentFilter filter = new IntentFilter();
        filter.addAction(LocationManager.HIGH_POWER_REQUEST_CHANGE_ACTION);
        context.registerReceiverAsUser(this, UserHandle.ALL, filter, null, new Handler(mHandlerThread.getLooper()));

        mAppOpsManager = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
        updateActiveLocationRequests();
    }

    /**
     * Add a callback to listen for changes in location settings.
     */
    public void addCallback(LocationChangeCallback cb) {
        mSettingsChangeCallbacks.add(cb);
        mHandler.sendEmptyMessage(H.MSG_LOCATION_ACTIVE_CHANGED);
    }

    public void removeCallback(LocationChangeCallback cb) {
        mSettingsChangeCallbacks.remove(cb);
    }

    @Override
    public void onReceive(Context context, Intent intent) {
        final String action = intent.getAction();
        if (LocationManager.HIGH_POWER_REQUEST_CHANGE_ACTION.equals(action)) {
            updateActiveLocationRequests();
        }
    }

    // Reads the active location requests and updates the status view if necessary.
    private void updateActiveLocationRequests() {
        boolean hadActiveLocationRequests = mAreActiveLocationRequests;
        mAreActiveLocationRequests = areActiveHighPowerLocationRequests();
        if (mAreActiveLocationRequests != hadActiveLocationRequests) {
            mHandler.sendEmptyMessage(H.MSG_LOCATION_ACTIVE_CHANGED);
        }
    }

    /**
     * Returns true if there currently exist active high power location requests.
     */
    @VisibleForTesting
    protected boolean areActiveHighPowerLocationRequests() {
        List<AppOpsManager.PackageOps> packages
                = mAppOpsManager.getPackagesForOps(mHighPowerRequestAppOpArray);
        // AppOpsManager can return null when there is no requested data.
        if (packages != null) {
            final int numPackages = packages.size();
            for (int packageInd = 0; packageInd < numPackages; packageInd++) {
                AppOpsManager.PackageOps packageOp = packages.get(packageInd);
                String packageName = packageOp.getPackageName();
                Log.d(TAG, "areActiveHighPowerLocationRequests: packageName1 = " + packageName);
                List<AppOpsManager.OpEntry> opEntries = packageOp.getOps();
                if (opEntries != null) {
                    final int numOps = opEntries.size();
                    for (int opInd = 0; opInd < numOps; opInd++) {
                        AppOpsManager.OpEntry opEntry = opEntries.get(opInd);
                        // AppOpsManager should only return OP_MONITOR_HIGH_POWER_LOCATION because
                        // of the mHighPowerRequestAppOpArray filter, but checking defensively.
                        if (opEntry.getOp() == AppOpsManager.OP_MONITOR_HIGH_POWER_LOCATION) {
                            if (opEntry.isRunning()) {
                                return true;
                            }
                        }
                    }
                }
            }
        }

        return false;
    }

    @Override
    public boolean isLocationActive() {
        return mAreActiveLocationRequests;
    }

    private final class H extends Handler {
        private static final int MSG_LOCATION_ACTIVE_CHANGED = 1;

        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case MSG_LOCATION_ACTIVE_CHANGED:
                    locationActiveChanged();
                    break;
            }
        }

        private void locationActiveChanged() {
            for (LocationChangeCallback callback : mSettingsChangeCallbacks) {
                callback.onLocationActiveChanged(isLocationActive());
            }
        }

    }
}

public interface LocationController {
    boolean isLocationActive();

    /**
     * A callback for change in location settings (the user has enabled/disabled location).
     */
    public interface LocationChangeCallback {
        /**
         * Called whenever location's state changes.
         *
         * @param active
         */
        default void onLocationActiveChanged(boolean active) {
        }
    }
}

结尾

参考文献： LocationControllerImpl