我正在编写一个应用程序来显示基于纬度和经度的用户当前地址但我在此代码中遇到一个错误Toast.makeText(this, "No address found try again", Toast.LENGTH_SHORT).show();这就是说类型toast中的makeText不适用于参数。我无法解决此错误。
任何帮助？
我试图在TextView中显示用户地址，但我不确定我是否做得好或将来可能会发生一些运行时错误。
这是我的主要活动java代码：
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.common.api.GoogleApiClient.ConnectionCallbacks;
import com.google.android.gms.common.api.GoogleApiClient.OnConnectionFailedListener;
import com.google.android.gms.location.LocationServices;
import android.app.Activity;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentSender.SendIntentException;
import android.location.Geocoder;
import android.location.Location;
import android.os.Bundle;
import android.os.Handler;
import android.os.ResultReceiver;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity implements OnItemSelectedListener, ConnectionCallbacks, OnConnectionFailedListener{
private static final int REQUEST_RESOLVE_ERROR = 1001;
private static final String DIALOG_ERROR = "dialog_error";
private static final String STATE_RESOLVING_ERROR = "resolving_error";
GoogleApiClient mGoogleApiClient;
protected Location mLastLocation;
private boolean mResolvingError=false;
private AddressResultReceiver mResultReceiver;
// Request code to use when launching the resolution activity
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Spinner spinner = (Spinner) findViewById(R.id.shop_category);
// Create an ArrayAdapter using the string array and a default spinner layout
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
R.array.shop_category, android.R.layout.simple_spinner_item);
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
spinner.setAdapter(adapter);
spinner.setOnItemSelectedListener(this);
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
mResolvingError = savedInstanceState != null
&& savedInstanceState.getBoolean(STATE_RESOLVING_ERROR, false);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
// TODO Auto-generated method stub
TextView mytext = (TextView) view;
Toast.makeText(this,"You selected "+mytext.getText(),Toast.LENGTH_SHORT).show();
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
// TODO Auto-generated method stub
}
protected void startIntentService() {
Intent intent = new Intent(this, FetchAddressIntentService.class);
intent.putExtra(Constants.RECEIVER, mResultReceiver);
intent.putExtra(Constants.LOCATION_DATA_EXTRA, mLastLocation);
startService(intent);
}
@Override
public void onConnected(Bundle arg0) {
boolean mAddressRequested=false;
// TODO Auto-generated method stub
TextView myLatitude = (TextView)findViewById(R.id.lat_value);
TextView myLongitude = (TextView)findViewById(R.id.lang_value);
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
myLatitude.setText(String.valueOf(mLastLocation.getLatitude()));
myLongitude.setText(String.valueOf(mLastLocation.getLongitude()));
if (!Geocoder.isPresent()) {
Toast.makeText(this, R.string.no_geocoder_available,
Toast.LENGTH_LONG).show();
return;
}
else{
mAddressRequested=true;
if (mAddressRequested) {
startIntentService();
}
}
}
}
@Override
public void onConnectionSuspended(int arg0) {
// TODO Auto-generated method stub
}
@Override
public void onConnectionFailed(ConnectionResult result) {
// TODO Auto-generated method stub
if (mResolvingError) {
Toast.makeText(this, "Resolving errors", Toast.LENGTH_SHORT).show();
return;
} else if (result.hasResolution()) {
try {
mResolvingError = true;
result.startResolutionForResult(this, REQUEST_RESOLVE_ERROR);
} catch (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;
}
}
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");
}
public void onDialogDismissed() {
mResolvingError = false;
}
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) {
((MainActivity) getActivity()).onDialogDismissed();
}
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_RESOLVE_ERROR) {
mResolvingError = false;
if (resultCode == RESULT_OK) {
if (!mGoogleApiClient.isConnecting() &&
!mGoogleApiClient.isConnected()) {
mGoogleApiClient.connect();
}
}
}
}
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putBoolean(STATE_RESOLVING_ERROR, mResolvingError);
}
protected void onStart() {
mGoogleApiClient.connect();
super.onStart();
}
protected void onStop() {
mGoogleApiClient.disconnect();
super.onStop();
}
class AddressResultReceiver extends ResultReceiver {
public AddressResultReceiver(Handler handler) {
super(handler);
}
@Override
protected void onReceiveResult(int resultCode, Bundle resultData) {
// Display the address string
// or an error message sent from the intent service.
String mAddressOutput = resultData.getString(Constants.RESULT_DATA_KEY);
// Show a toast message if an address was found.
if (resultCode == Constants.SUCCESS_RESULT) {
TextView myaddress=(TextView) findViewById(R.id.myaddress);
myaddress.setText(mAddressOutput);
}
else{
Toast.makeText(this, "No address found try again", Toast.LENGTH_SHORT).show();
}
}
}
}
提前谢谢。
答案 0 :(得分：1)
将this替换为MainActivity.this作为makeText()来电的第一个参数。 this是您AddressResultReceiver内部班级的一个实例。这不是您的活动，makeText()需要Context，例如Activity。
答案 1 :(得分：0)
使用getApplicationContext()代替this。使用：
Toast.makeText(getApplicationContext(), "message", Toast.LENGTH_SHORT).show();
this是指AddressResultReceiver，它不是Context的子类。
Toast.makeText()需要Context。