Question

我正在研究我的最终项目并且是Android新手。我想将速度从LocationManager传递给Activity，我试图用Intent传递它，我的意思是（Intent j = new Intent(this, CallblockingActivity.class)），但它不起作用。请帮帮我。

public class ShowLocationActivity extends Activity {
    private TextView latituteField;
    private TextView longitudeField;
    private TextView speed;
    public float a;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.locationmanager);
        latituteField = (TextView) findViewById(R.id.TextView02);
        longitudeField = (TextView) findViewById(R.id.TextView04);
        speed = (TextView)findViewById(R.id.textspeed);
        LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        LocationListener ll = new mylocationlistener();
        lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, ll);
    }


    private class mylocationlistener implements LocationListener {
        @Override
        public void  onLocationChanged(Location location) {
            if (location != null) {
                float lat = (float) (location.getLatitude());
                float lng = (float) (location.getLongitude());
                latituteField.setText(String.valueOf(lat));
                longitudeField.setText(String.valueOf(lng));
                a=location.getSpeed();
                speed.setText("current speed" + a);

                *** **My problwm is here,I just want to pass a**


                Log.d("LOCATION CHANGED", location.getLatitude() + "");
                Log.d("LOCATION CHANGED", location.getLongitude() + "");
                Toast.makeText(ShowLocationActivity.this,
                        location.getLatitude() + "" + location.getLongitude(),
                        Toast.LENGTH_LONG).show();
            }
        }
        @Override
        public void onProviderDisabled(String provider) {
        }
        @Override
        public void onProviderEnabled(String provider) {
        }
        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {
        }
    }
}

Answer 1

只需使用Intent#putExtra()：

Intent j = new Intent(ShowLocationActivity.this, CallblockingActivity.class);
j.putExtra("Speed", a);
startActivity(j);

在你的新活动中，阅读速度：

Intent intent = getIntent();
float speed = intent.getFloatExtra("Speed", 0); // 0 is the default case

如何将速度从LocationManager传递到Activity？

1 个答案: