Develop Reference

Passing strings to AsyncTask.execute in android?

Im trying to make a weather app in android where i get input from user and then tell them the current weather. main activity looks like this
package com.example.dellinspiron.speechrecognition;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.graphics.Typeface;
import android.text.Html;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
TextView cityField, detailsField, currentTemperatureField, humidity_field, pressure_field, weatherIcon, updatedField;
Typeface weatherFont;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().hide();
setContentView(R.layout.activity_main);
Button b=(Button)findViewById(R.id.button);
assert b != null;
b.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
EditText c=(EditText)findViewById(R.id.city);
EditText d=(EditText)findViewById(R.id.country);
final String city=c.getText().toString();
final String country=d.getText().toString();
weatherFont = Typeface.createFromAsset(getApplicationContext().getAssets(), "fonts/weathericons-regular-webfont.ttf");
cityField = (TextView)findViewById(R.id.city_field);
updatedField = (TextView)findViewById(R.id.updated_field);
detailsField = (TextView)findViewById(R.id.details_field);
currentTemperatureField = (TextView)findViewById(R.id.current_temperature_field);
humidity_field = (TextView)findViewById(R.id.humidity_field);
pressure_field = (TextView)findViewById(R.id.pressure_field);
weatherIcon = (TextView)findViewById(R.id.weather_icon);
weatherIcon.setTypeface(weatherFont);
Function.placeIdTask asyncTask =new Function.placeIdTask(new Function.AsyncResponse() {
public void processFinish(String weather_city, String weather_description, String weather_temperature, String weather_humidity, String weather_pressure, String weather_updatedOn, String weather_iconText, String sun_rise) {
cityField.setText(weather_city);
updatedField.setText(weather_updatedOn);
detailsField.setText(weather_description);
currentTemperatureField.setText(weather_temperature);
humidity_field.setText("Humidity: "+weather_humidity);
pressure_field.setText("Pressure: "+weather_pressure);
weatherIcon.setText(Html.fromHtml(weather_iconText));
}
});
asyncTask.execute(city, country); // having problems here
}
});
}
when i try to explicitly pass the city name and country eg asyncTask.execute("rawalpindi", "Pakistan") it works, but then if i try to pass a string obtained from the text box it doesnt.
i have tried to get output of the string and it gives the correct output but it just isnt being passed to the execute function properly. please help.

Try to trim the string using trim() method when you obtain the text from EditText as extra spaces may cause the error in the result.

iterating a global list from any activity

i have a list of object in an activity in which a button in the same activity adds an object to it on every click
i want to be capable to access that list and iterate it from any other activity
i made it public but it gave me an error !
package com.fawzyx.movie_rental_store;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MovieReg_activity extends Activity {
public List<movie> movies = new ArrayList<movie>();
String movName ;
int dvdNo ;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.mov_reg_layout);
EditText etmovie_name = (EditText)findViewById(R.id.etmovname);
EditText etdvd_no = (EditText)findViewById(R.id.etdvds);
Button btMovie_submit = (Button)findViewById(R.id.btmovsubmit);
movName= etmovie_name.getText().toString();
dvdNo = Integer.parseInt(etdvd_no.getText().toString()); // to string then to int :)
btMovie_submit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
movies.add(new movie(movName , dvdNo) );
Toast.makeText(MovieReg_activity.this, "Movie Added", Toast.LENGTH_LONG).show();
}
});
}
}
is there a way to access and iterate the list movies from any other activity ?

You can use a static way to access to this list :
public static List<movie> movies = new ArrayList<movie>();
Then from the other activity :
int size = MovieReg_activity.movies.size(); // exp: check the size
for(movie m : MovieReg_activity.movies){
// do something with m
}

if you want to make a global list, create a static variable or put it in your application class and access it via context.
Search about creating a custom application class.

Maybe use a singleton class that holds your movie list.
Then you'll be able to access it everywhere.
http://androidresearch.wordpress.com/2012/03/22/defining-global-variables-in-android/

The string concatenation is not displayed

I have a problem with the concatenation of the strings that I will I enter.
This is the class:
package com.isma.multisitesearch.Siti;
import com.isma.multisitesearch.R;
import com.isma.multisitesearch.Webviews.GoogleWebView;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
public class Google extends Activity implements OnClickListener {
private String TAG_ACT = "Caricamento ricerca";
public EditText googletext;
private Button googlebutton;
private String googleurl = "https://www.google.it/search?q=";
public static String newgoogleurl;
public String space = " ";
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.google);
googletext = (EditText) findViewById(R.id.googletext);
googlebutton = (Button) findViewById(R.id.googlebutton);
googlebutton.setOnClickListener(this);
newgoogleurl = googleurl + googletext.getText().toString();
newgoogleurl.replaceAll(space, "%20");
System.out.println(newgoogleurl);
}
#Override
public void onClick(View v) {
Log.v(TAG_ACT, "in corso");
Intent intent = new Intent(Google.this, GoogleWebView.class);
startActivity(intent);
}
}
And this is the WebView to which I want to get the concatenation:
package com.isma.multisitesearch.Webviews;
import com.isma.multisitesearch.R;
import com.isma.multisitesearch.Siti.Google;
import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebView;
import android.webkit.WebViewClient;
public class GoogleWebView extends Activity {
private WebView googlewebview;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.googlewebview);
googlewebview = (WebView) findViewById(R.id.googlewebview);
googlewebview.getSettings().setJavaScriptEnabled(true);
googlewebview.getSettings().setLoadsImagesAutomatically(true);
googlewebview.setWebViewClient(new WebViewClient());
googlewebview.loadUrl(Google.newgoogleurl);
}
}
The app works fine but when I go to write the search text in the EditText, the google but I get the main page where you can enter the search instead of the url with already entered the search text.
I hope you know to help me, after this I was able to run the app.

Try this:
#Override
public void onClick(View v) {
newgoogleurl = googleurl + googletext.getText().toString();
newgoogleurl = newgoogleurl.replaceAll(space, "%20");
Log.v(TAG_ACT, "in corso");
Intent intent = new Intent(Google.this, GoogleWebView.class);
startActivity(intent);
}

Note that
newgoogleurl.replaceAll(space, "%20");
has no effect, you need to code:
newgoogleurl = newgoogleurl.replaceAll(space, "%20");
Have a look here:
http://javarevisited.blogspot.it/2011/12/java-string-replace-example-tutorial.html

Try below code:
String url;
url = googleurl+googletext.getText().toString();
if( url.contains(" ")){
newgoogleurl=url.replaceAll(" ","%20");
}else{
newgoogleurl=url;
}
This is containing validation part also.

Strings are immutable. That means that you cannot modify an instance of String, and need to create a new one each time you want to modify it.
In your case, replaceAll does not modify the String you call it on, but rather returns a new String with your modification applied.
Which is why you need to affect the returned value to the reference of your String.
newgoogleurl = newgoogleurl.replaceAll(space, "%20");
Moreover, you should read the documentation for replaceAll, because I don't think it does what you want. You probably want to use replace.

HTMLcleaner in AsyncTask

I am trying to get HTML cleaner to parse the info from a website and then use Xpath to find the data I'm looking for. I have the htmlcleaner stuff in a separate AsyncTask class and the app seems to work on my phone. However, when I push the button nothing happens. Here is my main activity class and my AsyncTask Class.
package ru.habrahabr.stackparser;
import java.net.URL;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.htmlcleaner.TagNode;
import android.app.Activity;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.*;
public class stackParser extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button button = (Button) findViewById(R.id.parse);
button.setOnClickListener(myListener);
}
private OnClickListener myListener = new OnClickListener() {
public void onClick(View v) {
new parseSite().execute("http://xjaphx.wordpress.com/");
}
};
private class parseSite extends AsyncTask<String, Void, String> {
protected String doInBackground(String... arg) {
String output = new String();
try {
htmlHelper hh = new htmlHelper();
} finally {
}
return output;
}
protected void onPostExecute(String output) {
TextView view = (TextView) findViewById(R.id.tv1);
view.setText((CharSequence) output);
}
}
}
And here's my referenced class. I'd really appreciate it if someone could look at this and tell me what's up. I tried to follow a working example and put my own Url and Xpath in but it's not working.
package ru.habrahabr.stackparser;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import org.htmlcleaner.HtmlCleaner;
import org.htmlcleaner.TagNode;
import org.htmlcleaner.XPatherException;
public class htmlHelper {
TagNode rootNode;
String stats;
static final String XPATH_STATS = "//div[#id='blog-stats']/ul/li";
public String htmlHelper(URL htmlPage) throws IOException, XPatherException {
HtmlCleaner cleaner = new HtmlCleaner();
rootNode = cleaner.clean(htmlPage);
// query XPath
Object[] statsNode = rootNode.evaluateXPath(XPATH_STATS);
// process data if found any node
if (statsNode.length > 0) {
TagNode resultNode = (TagNode) statsNode[0];
stats = resultNode.getText().toString();
}
return stats;
}
}

Change AsyncTask doInBackground method as :
#Override
protected String doInBackground(String... arg) {
String output "";
try {
htmlHelper hh = new htmlHelper();
output=hh.htmlHelper(arg[0]); //<< call htmlHelper method here
} finally {
}
return output;
}
because you are currently only creating an instance of htmlHelper class not calling htmlHelper method from htmlHelper class to get data from web url

Look , I will not care of the data is downloaded or not , but I will assume that the data is already downloaded and besides in the variable output , you just need to place this code inside onPostExecute
runOnUiThread(new Runnable() {
public void run() {
// update data into TextView.
TextView view = (TextView) findViewById(R.id.tv1);
view.setText((CharSequence) output);
}
});
because , sometimes the data is already downloaded but needed to be assigned into Textview or whatever view by using UIthread. Hope this works for you

Attachment sent through email is of 0KB size

I am developing an application in which I have to send an image through email. I succeeded in sending email, but the attachment sent is of 0KB size. I am not getting what is the problem. Below, I am posting my code.
import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
public class EtestActivity extends Activity {
/** Called when the activity is first created. */
Button email;
Intent in;
private static final String TAG = "EmailLauncherActivity";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
email = (Button)findViewById(R.id.email);
email.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
try {
in = new Intent(Intent.ACTION_SEND);
in.setType("image/jpeg");
in.putExtra(Intent.EXTRA_STREAM, Uri.parse("file:///sdcard/android.jpg"));
startActivity(Intent.createChooser(in, "Email..."));
} catch (Exception e) {
Log.e(TAG, "email sending failed", e);
}//catch
}//onClick
});
}//onCreate
}//class

I also face the same problem which is solved by changing MIME type.
Try this in.setType("image/jpg");

Was your phone mounted to your computer at the time? The SD card may be inaccessible while connected to your computer, so it may not actually be attaching the image.