我正在开发一款跟踪您跑步距离的Android应用。我希望能够同时使用其他应用程序，如音乐应用程序。我没有找到关于如何在后台运行应用程序的任何好的教程，如果有人知道任何好的教程或一个简单的解决方案，让应用程序在后台运行，如果你愿意与我分享，我真的很赞。 / p>
申请代码：
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentSender;
import android.location.Location;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GoogleApiAvailability;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.common.SupportErrorDialogFragment;
import java.text.DateFormat;
import java.util.Date;
public class StepCounter extends FragmentActivity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
// Request code to use when launching the resolution activity
private static final int REQUEST_RESOLVE_ERROR = 1001;
// Unique tag for the error dialog fragment
private static final String DIALOG_ERROR = "dialog_error";
// Bool to track whether the app is already resolving an error
private boolean mResolvingError = false;
//keys
GoogleApiClient mGoogleApiClient;
TextView mLatitudeText;
TextView mLongitudeText;
TextView mcLatitudeText;
TextView mcLongitudeText;
TextView mDistanceText;
Location mLastLocation;
Location mCurrentLocation;
double d=0.0;
double lat1;
double lat2;
double lon1;
double lon2;
double dlat;
double dlon;
double raz=6371000;
double a;
double c;
LocationRequest mLocationRequest;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_step_counter);
mLatitudeText = (TextView) findViewById(R.id.lat);
mLongitudeText = (TextView) findViewById(R.id.lon);
mcLatitudeText = (TextView) findViewById(R.id.llat);
mcLongitudeText = (TextView) findViewById(R.id.llon);
mDistanceText = (TextView) findViewById(R.id.dist);
mResolvingError = savedInstanceState != null
&& savedInstanceState.getBoolean(STATE_RESOLVING_ERROR, false);
createLocationRequest();
buildGoogleApiClient();
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
@Override
protected void onStart() {
super.onStart();
if(!mResolvingError)
mGoogleApiClient.connect();
}
@Override
protected void onStop() {
mGoogleApiClient.disconnect();
super.onStop();
}
public void onConnected(Bundle connectionHint) {
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
mCurrentLocation = mLastLocation;
if (mLastLocation != null) {
mLatitudeText.setText(String.valueOf(mLastLocation.getLatitude()));
mLongitudeText.setText(String.valueOf(mLastLocation.getLongitude()));
}
//modified
startLocationUpdates();
}
//pana aici merge de aici vine partea cu update
protected void startLocationUpdates() {
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient, mLocationRequest, this);
}
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(500);
mLocationRequest.setFastestInterval(500);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
@Override
public void onLocationChanged(Location location) {
mLastLocation = mCurrentLocation;
mCurrentLocation = location;
updateDistance();
updateUI();
}
public void updateUI()
{
mLatitudeText.setText(String.valueOf(mLastLocation.getLatitude()));
mLongitudeText.setText(String.valueOf(mLastLocation.getLongitude()));
mcLatitudeText.setText(String.valueOf(mCurrentLocation.getLatitude()));
mcLongitudeText.setText(String.valueOf(mCurrentLocation.getLongitude()));
}
public void updateDistance()
{
lat1=Math.toRadians(mLastLocation.getLatitude());
lat2=Math.toRadians(mCurrentLocation.getLatitude());
lon1=Math.toRadians(mLastLocation.getLongitude());
lon2=Math.toRadians(mCurrentLocation.getLongitude());
dlat=Math.toRadians(lat2-lat1);
dlon=Math.toRadians(lon2-lon1);
a = Math.sin(dlat/2) * Math.sin(dlat/2) + Math.cos(lat1) * Math.cos(lat2) * Math.sin(dlon/2) * Math.sin(dlon/2);
c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
d += raz * c;
mDistanceText.setText(String.valueOf(d));
}
//@Override
protected void onPause() {
super.onPause();
stopLocationUpdates();
}
protected void stopLocationUpdates() {
LocationServices.FusedLocationApi.removeLocationUpdates(
mGoogleApiClient, this);
}
@Override
public void onResume() {
super.onResume();
if (mGoogleApiClient.isConnected()) {
startLocationUpdates();
}
}
// De aici partea cu rezolvatu problemei
@Override
public void onConnectionSuspended(int i) {
//todo nust...
}
@Override
public void onConnectionFailed(ConnectionResult result) {
if (mResolvingError) {
// Already attempting to resolve an error.
return;
} else if (result.hasResolution()) {
try {
mResolvingError = true;
result.startResolutionForResult(this, REQUEST_RESOLVE_ERROR);
} catch (IntentSender.SendIntentException e) {
// There was an error with the resolution intent. Try again.
mGoogleApiClient.connect();
}
} else {
// Show dialog using GoogleApiAvailability.getErrorDialog()
showErrorDialog(result.getErrorCode());
mResolvingError = true;
}
}
// The rest of this code is all about building the error dialog
/* Creates a dialog for an error message */
private void showErrorDialog(int errorCode) {
// Create a fragment for the error dialog
ErrorDialogFragment dialogFragment = new ErrorDialogFragment();
// Pass the error that should be displayed
Bundle args = new Bundle();
args.putInt(DIALOG_ERROR, errorCode);
dialogFragment.setArguments(args);
dialogFragment.show(getFragmentManager(), "errordialog");
}
/* Called from ErrorDialogFragment when the dialog is dismissed. */
public void onDialogDismissed() {
mResolvingError = false;
}
/* A fragment to display an error dialog */
public static class ErrorDialogFragment extends DialogFragment {
public ErrorDialogFragment() { }
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Get the error code and retrieve the appropriate dialog
int errorCode = this.getArguments().getInt(DIALOG_ERROR);
return GoogleApiAvailability.getInstance().getErrorDialog(
this.getActivity(), errorCode, REQUEST_RESOLVE_ERROR);
}
@Override
public void onDismiss(DialogInterface dialog) {
((StepCounter) getActivity()).onDialogDismissed();
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_RESOLVE_ERROR) {
mResolvingError = false;
if (resultCode == RESULT_OK) {
// Make sure the app is not already connected or attempting to connect
if (!mGoogleApiClient.isConnecting() &&
!mGoogleApiClient.isConnected()) {
mGoogleApiClient.connect();
}
}
}
}
private static final String STATE_RESOLVING_ERROR = "resolving_error";
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putBoolean(STATE_RESOLVING_ERROR, mResolvingError);
}
}
答案 0 :(得分：3)
您可以根据自己的要求使用Service。
这是一个长期工作的应用程序组件 背景，不显示用户界面。如果另一个 应用程序组件启动服务，用户切换到 另一个应用程序，该服务可以继续运行 背景
答案 1 :(得分：0)
您可以使用在设置时以不同间隔运行的wakefulintentservice。这里有一些例子： http://www.programcreek.com/java-api-examples/index.php?api=com.commonsware.cwac.wakeful.WakefulIntentService
这是推荐的，因为当慢跑时屏幕关闭时，标准服务不能保持运行。
至于上面的评论，您需要从UI绑定到服务，然后您就可以调用服务上的方法。阅读文档......