我有一个RemoteCar Control应用程序，在MainActivity页面上有一个按钮“location”，您可以单击该按钮以重定向到另一个活动（locationActivity）。在此活动中，我在Listview中显示JSON文件，现在我想点击这些对象来选择它们，并在主页面上显示类似于简单TextView的位置，没有什么特别之处。我怎么能这样做？
这是我的位置页面：
public class location extends AppCompatActivity {
private String TAG = location.class.getSimpleName();
private ListView lv;
ArrayList<HashMap<String, String>> locationList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_location);
locationList = new ArrayList<>();
lv = (ListView) findViewById(R.id.list);
new GetContacts().execute();
}
private class GetContacts extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
Toast.makeText(location.this, "Json Data is downloading", Toast.LENGTH_LONG).show();
}
@Override
protected Void doInBackground(Void... arg0) {
HttpHandler sh = new HttpHandler();
// Making a request to url and getting response
String url = "url";
String jsonStr = sh.makeServiceCall(url);
Log.e(TAG, "Response from url: " + jsonStr);
if (jsonStr != null) {
try {
//JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
//JSONArray locations = jsonObj.getJSONArray("");
JSONArray locations_ = new JSONArray(jsonStr);
// looping through All Contacts
for (int i = 0; i < locations_.length(); i++) {
JSONObject c = locations_.getJSONObject(i);
String type = c.getString("type");
String name = c.getString("name");
String address = c.getString("address");
String lat = c.getString("lat");
String lon = c.getString("lon");
String icon;
if(c.has("icon")){
//your json is having "icon" Key, get the value
icon = c.getString("icon");
}
else{
//your json is NOT having "icon" Key, assign a dummy value
icon = "/default/icon_url()";
}
// tmp hash map for single contact
HashMap<String, String> location = new HashMap<>();
// adding each child node to HashMap key => value
location.put("type", type);
location.put("name", name);
location.put("address", address );
location.put("lat", lat);
location.put("lon", lon);
location.put("icon", icon);
// adding contact to contact list
locationList.add(location);
}
} catch (final JSONException e) {
Log.e(TAG, "Json parsing error: " + e.getMessage());
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Json parsing error: " + e.getMessage(),
Toast.LENGTH_LONG).show();
}
});
}
} else {
Log.e(TAG, "Couldn't get json from server.");
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Couldn't get json from server. Check LogCat for possible errors!",
Toast.LENGTH_LONG).show();
}
});
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
ListAdapter adapter = new SimpleAdapter(location.this, locationList,
R.layout.list_item, new String[]{"type", "name", "address", "lat", "lon", "icon"},
new int[]{R.id.type, R.id.name, R.id.address, R.id.lat, R.id.lon, R.id.icon});
lv.setAdapter(adapter);
}
}
这是我的MainActivity页面
public class MainActivity extends AppCompatActivity {
public ProgressBar fuelBar;
public Button lockButton;
public Button engButton;
public Button refuelButton;
public Button locationButton;
public SeekBar seekBarButton;
public TextView seekText;
int incFuel = 0;
final String FUELBAR = "fuelBar";
final String AC_BARTEXT = "acBarText";
final String AC_BAR = "acBar";
final String REFUELBUTTON = "refuelButton";
final String STARTENGINE = "startEngineButton";
SharedPreferences sharedPref;
SharedPreferences.Editor editor;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
locationButton = (Button) findViewById(R.id.locationB);
lockButton = (Button) findViewById(R.id.lockB);
engButton = (Button) findViewById(R.id.engB);
refuelButton = (Button) findViewById(R.id.refuelB);
fuelBar = (ProgressBar) findViewById(R.id.fuelProgressBar);
fuelBar.setMax(100);
fuelBar.setProgress(30);
refuelButton.setText(R.string.refuelB);
lockButton.setText(R.string.lockB);
locationButton.setText(R.string.locationB);
engButton.setText(R.string.engB);
seekBarButton = (SeekBar) findViewById(R.id.seekBar);
seekText = (TextView) findViewById(R.id.seekText);
sharedPref = getPreferences(Context.MODE_PRIVATE);
editor = sharedPref.edit();
seek_bar();
lockPage();
locationPage();
}
@Override
protected void onPause(){
super.onPause();
editor.putInt(FUELBAR, fuelBar.getProgress());
editor.commit();
String tmpAC = "AC : " + String.valueOf(seekBarButton.getProgress()+18) + "°";
editor.putString(AC_BARTEXT, tmpAC);
editor.commit();
editor.putInt(AC_BAR, seekBarButton.getProgress());
editor.commit();
editor.putString(REFUELBUTTON, refuelButton.getText().toString());
editor.commit();
editor.putString(STARTENGINE, engButton.getText().toString());
editor.commit();
}
@Override
public void onResume(){
super.onResume();
fuelBar = (ProgressBar) findViewById(R.id.fuelProgressBar);
incFuel = sharedPref.getInt(FUELBAR, 0);
fuelBar.setProgress(incFuel);
seekText = (TextView) findViewById(R.id.seekText);
String tmpAC = sharedPref.getString(AC_BARTEXT, "error");
seekText.setText(tmpAC);
seekBarButton = (SeekBar) findViewById(R.id.seekBar);
int tmpInt = sharedPref.getInt(AC_BAR, 18);
seekBarButton.setProgress(tmpInt);
tmpAC = sharedPref.getString(REFUELBUTTON, "REFUEL");
refuelButton.setText(tmpAC);
tmpAC = sharedPref.getString(STARTENGINE, "START ENGINE");
engButton.setText(tmpAC);
}
@Override
public void onStop(){
super.onStop();
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.engB:
if (engButton.getText() == "ENGINE RUNNING") {
engButton.setText("START ENGINE");
} else {
if (fuelBar.getProgress() > 0) {
Toast.makeText(MainActivity.this, "starting engine..", Toast.LENGTH_SHORT).show();
engButton.setText("ENGINE RUNNING");
if (fuelBar.getProgress() >= 10) {
incFuel = fuelBar.getProgress();
incFuel -= 10;
fuelBar.setProgress(incFuel);
if (fuelBar.getProgress() < 100)
refuelButton.setText("REFUEL");
}
} else if (fuelBar.getProgress() == 0) {
Toast.makeText(MainActivity.this, "no fuel", Toast.LENGTH_SHORT).show();
engButton.setText("EMPTY GASTANK");
} else
engButton.setText("START ENGINE");
}
break;
case R.id.refuelB:
if (fuelBar.getProgress() == 0) {
engButton.setText("START ENGINE");
incFuel = fuelBar.getProgress();
incFuel += 10;
fuelBar.setProgress(incFuel);
} else if (fuelBar.getProgress() < 100) {
incFuel = fuelBar.getProgress();
incFuel += 10;
fuelBar.setProgress(incFuel);
} else {
Toast.makeText(MainActivity.this, "tank is full", Toast.LENGTH_SHORT).show();
refuelButton.setText("FULL");
}
break;
}
}
public void seek_bar() {
seekBarButton = (SeekBar) findViewById(R.id.seekBar);
seekText = (TextView) findViewById(R.id.seekText);
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
seekBarButton.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
int progressNum;
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
progressNum = progress;
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
}
});
}
public void lockPage() {
lockButton = (Button) findViewById(R.id.lockB);
lockButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent lockPage = new Intent(MainActivity.this, lockDoor.class);
startActivity(lockPage);
}
});
}
public void locationPage() {
locationButton = (Button) findViewById(R.id.locationB);
locationButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent locationPage = new Intent(MainActivity.this, location.class);
startActivity(locationPage);
}
});
}
}
对于代码墙我很难不确定要提供多少信息。
答案 0 :(得分：0)
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(MyActivity.this, "location:" + " "+ stringList[position] + " " + "hauptbahnhof selected", Toast.LENGTH_SHORT).show();
}
});
define your list of string as private out of onCreate