How to open standard Google Map application from my application?

Solution:

You should create an Intent object with a geo-URI:

String uri = String.format(Locale.ENGLISH, "geo:%f,%f", latitude, longitude);
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
context.startActivity(intent);

If you want to specify an address, you should use another form of geo-URI: geo:0,0?q=address.

reference : https://developer.android.com/guide/components/intents-common.html#Maps


You can also simply use http://maps.google.com/maps as your URI

String uri = "http://maps.google.com/maps?saddr=" + sourceLatitude + "," + sourceLongitude + "&daddr=" + destinationLatitude + "," + destinationLongitude;
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
startActivity(intent);

or you can make sure that the Google Maps app only is used, this stops the intent filter (dialog) from appearing, by using

intent.setPackage("com.google.android.apps.maps");

like so:

String uri = "http://maps.google.com/maps?saddr=" + sourceLatitude + "," + sourceLongitude + "&daddr=" + destinationLatitude + "," + destinationLongitude;
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
intent.setPackage("com.google.android.apps.maps");
startActivity(intent);

or you can add labels to the locations by adding a string inside parentheses after each set of coordinates like so:

String uri = "http://maps.google.com/maps?saddr=" + sourceLatitude + "," + sourceLongitude + "(" + "Home Sweet Home" + ")&daddr=" + destinationLatitude + "," + destinationLongitude + " (" + "Where the party is at" + ")";
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
intent.setPackage("com.google.android.apps.maps");
startActivity(intent);

To use the users current location as the starting point (unfortunately I haven't found a way to label the current location) then just drop off the saddr parameter as follows:

String uri = "http://maps.google.com/maps?daddr=" + destinationLatitude + "," + destinationLongitude + " (" + "Where the party is at" + ")";
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
intent.setPackage("com.google.android.apps.maps");
startActivity(intent);

For completeness, if the user doesn't have the maps app installed then it's going to be a good idea to catch the ActivityNotFoundException, as @TonyQ states, then we can start the activity again without the maps app restriction, we can be pretty sure that we will never get to the Toast at the end since an internet browser is a valid application to launch this url scheme too.

        String uri = "http://maps.google.com/maps?daddr=" + 12f + "," + 2f + " (" + "Where the party is at" + ")";
        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
        intent.setPackage("com.google.android.apps.maps");
        try
        {
            startActivity(intent);
        }
        catch(ActivityNotFoundException ex)
        {
            try
            {
                Intent unrestrictedIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
                startActivity(unrestrictedIntent);
            }
            catch(ActivityNotFoundException innerEx)
            {
                Toast.makeText(this, "Please install a maps application", Toast.LENGTH_LONG).show();
            }
        }

EDIT:

For directions, a navigation intent is now supported with google.navigation

Uri navigationIntentUri = Uri.parse("google.navigation:q=" + 12f + "," + 2f);
Intent mapIntent = new Intent(Intent.ACTION_VIEW, navigationIntentUri);
mapIntent.setPackage("com.google.android.apps.maps");
startActivity(mapIntent);

Using String format will help but you must be care full with the locale. In germany float will be separates with in comma instead an point.

Using String.format("geo:%f,%f",5.1,2.1); on locale english the result will be "geo:5.1,2.1" but with locale german you will get "geo:5,1,2,1"

You should use the English locale to prevent this behavior.

String uri = String.format(Locale.ENGLISH, "geo:%f,%f", latitude, longitude);
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
context.startActivity(intent);

To set an label to the geo point you can extend your geo uri by using:

!!! but be carefull with this the geo-uri is still under develoment http://tools.ietf.org/html/draft-mayrhofer-geo-uri-00

String uri = String.format(Locale.ENGLISH, "geo:%f,%f?z=%d&q=%f,%f (%s)", 
                           latitude, longitude, zoom, latitude, longitude, label);
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
context.startActivity(intent);