所以，我一直想要一个简单的＆＃34;任务管理器应用程序工作，但我遇到了onResume（）方法的糟糕情况。我想按下一个名为＆＃34; use_this_location的按钮后，抓住用户输入的地址的第一行。＆＃34;当我覆盖onResume（）方法时，我尝试将用户拥有的地址文本设置为TextView，但onResume（）上的地址似乎总是为空，我相信它是因为该方法在我所期待的不同时间。
我的措辞可能不合适，但我希望我能很好地解释这一情况。
AddLocationMapActivity：地址在mapCurrentAddress（）中设置，我使用setOnClickListener（）为useLocationButton在setUpViews（）中设置新的Intent。
public class AddLocationMapActivity extends FragmentActivity implements OnMapReadyCallback {
public static final String ADDRESS_RESULT = "address";
private GoogleMap mMap;
private UiSettings mUiSettings;
private Button mapLocationButton;
private Button useLocationButton;
private EditText addressText;
private Address address;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_location_maps);
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
mUiSettings = mMap.getUiSettings();
// Add zoom buttons
mUiSettings.setZoomControlsEnabled(true);
setUpViews();
}
private void setUpViews() {
addressText = (EditText) findViewById(R.id.task_address);
mapLocationButton = (Button) findViewById(R.id.map_location_button);
useLocationButton = (Button) findViewById(R.id.use_this_location_button);
useLocationButton.setEnabled(false);
useLocationButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
if (address != null) {
Intent intent = new Intent();
intent.putExtra(ADDRESS_RESULT, address);
setResult(RESULT_OK, intent);
}
finish();
}
});
mapLocationButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
mapCurrentAddress();
}
});
}
protected void mapCurrentAddress() {
String location = addressText.getText().toString();
List<Address> addresses;
if (location != null || !location.equals("")) {
Geocoder geocoder = new Geocoder(this);
try {
addresses = geocoder.getFromLocationName(location, 1);
if (addresses.size() > 0) {
address = addresses.get(0);
LatLng latLng = new LatLng(address.getLatitude(), address.getLongitude());
CameraUpdate center = CameraUpdateFactory.newLatLng(latLng);
CameraUpdate zoom = CameraUpdateFactory.zoomTo(12);
mMap.moveCamera(center);
mMap.addMarker(new MarkerOptions().position(latLng).title("Marker"));
mMap.animateCamera(zoom);
useLocationButton.setEnabled(true);
} else {
// show the user a note that we failed to get an address
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
AddTaskActivity：在onResume（）方法中，我尝试将TextView的文本设置为用户为AddLocationMapActivity键入的地址的第一行，但由于某种原因，地址始终为NULL。如果有人能帮我辨认我的错误，我真的很感激。我可能会误用onResume（），或者我可能会以错误的方式抓取地址。
public class AddTaskActivity extends TaskManagerActivity {
private static final int REQUEST_CHOOSE_ADDRESS = 0;
private EditText taskNameEditText;
private Button addButton;
private Button cancelButton;
private boolean changesPending;
private AlertDialog unsavedChangesDialog;
private Button addLocationButton;
private Address address;
private TextView addressText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add_tasks);
setUpViews();
}
@Override
protected void onResume() {
super.onResume();
if (address == null) {
addLocationButton.setVisibility(View.VISIBLE);
addressText.setVisibility(View.GONE);
//addressText.setVisibility(View.VISIBLE);
//addressText.setText("ADDRESS ALWAYS NULL");
} else {
addLocationButton.setVisibility(View.GONE);
addressText.setVisibility(View.VISIBLE);
addressText.setText(address.getAddressLine(0));
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_CHOOSE_ADDRESS && requestCode == RESULT_OK) {
address = data.getParcelableExtra(AddLocationMapActivity.ADDRESS_RESULT);
} else {
super.onActivityResult(requestCode, resultCode, data);
}
}
private void setUpViews() {
taskNameEditText = (EditText) findViewById(R.id.task_name);
addButton = (Button) findViewById(R.id.add_button);
cancelButton = (Button) findViewById(R.id.cancel_button);
addLocationButton = (Button) findViewById(R.id.add_location_button);
addressText = (TextView) findViewById(R.id.address_text);
addButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
addTask();
}
});
cancelButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
cancel();
}
});
addLocationButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(AddTaskActivity.this, AddLocationMapActivity.class);
startActivityForResult(intent, REQUEST_CHOOSE_ADDRESS);
}
});
taskNameEditText.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
changesPending = true;
}
@Override
public void afterTextChanged(Editable s) {
}
});
}
protected void addTask() {
String taskName = taskNameEditText.getText().toString();
if (!taskName.equals("")) {
Task t = new Task(taskName);
getTaskManagerApplication().addTask(t);
}
finish();
}
public void addLocationButtonClicked(View view) {
Intent intent = new Intent(this, AddLocationMapActivity.class);
startActivityForResult(intent, REQUEST_CHOOSE_ADDRESS);
}
protected void cancel() {
String taskName = taskNameEditText.getText().toString();
if (changesPending && !taskName.equals("")) {
unsavedChangesDialog = new AlertDialog.Builder(this)
.setTitle(R.string.unsaved_changes_title)
.setMessage(R.string.unsaved_changes_message)
.setPositiveButton(R.string.add_task, new AlertDialog.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
addTask();
}
})
.setNeutralButton(R.string.discard, new AlertDialog.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
finish();
}
})
.setNegativeButton(android.R.string.cancel, new AlertDialog.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
unsavedChangesDialog.cancel();
}
})
.create();
unsavedChangesDialog.show();
} else {
finish();
}
}
}