Database Develop

Android Studio Error MainActivity class Help

Hey guys.I am getting these errors in MainActivity java file when I create new project.I am a newbie.
package com.gaama.learnit;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends AppCompatActivity {
@override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

Okay guys its okay now.Admin you can remove the post

Pass data from one activity to another

Can you help me. I have developed a app with a quiz. When the quiz is finished a new activity (result) appears showing the score. I want to pass the score to a new activity namely score. Here is my code. What is wrong. The score must be showed in a textview.
Result.java
Code:
package app.mobiledevicesecurity;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class Result extends Activity
{
private static Button playbtn;
private static Button menubutton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_result);
OnClickPlayButtonListener();
OnClickMenuButtonListener();
TextView textResult = (TextView) findViewById(R.id.textResult);
Bundle b = getIntent().getExtras();
int score = b.getInt("score");
textResult.setText("You scored" + " " + score + " for the quiz.");
Intent i = new Intent(getApplicationContext(), Result.class);
i.putExtra("somevariable",score);
startActivity(i);
}
public void OnClickPlayButtonListener() {
playbtn = (Button) findViewById(R.id.btn);
playbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("app.mobiledevicesecurity.Quiz");
startActivity(intent);
}
}
);
}
public void OnClickMenuButtonListener() {
menubutton = (Button) findViewById(R.id.menubtn);
menubutton.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(getApplicationContext(), MainActivity.class);
startActivity(intent);
}
}
);
}
Scores.java
Code:
package app.mobiledevicesecurity;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.content.Intent;
public class Scores extends ActionBarActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_scores);
Intent intent = getIntent();
String value = intent.getStringExtra("somevariable");
TextView txtScore1 = (TextView) findViewById(R.id.txtScore1);
txtScore1.setText("You scored" + " " + value + " for the quiz.");
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_scores, 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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

Try this
In Result.java
i.putExtra("somevariable",score);alter this code like below..
i.putExtra("somevariable", score.toString());
you are passing integer and getting as string..try to pass it as string may help
or simply change this in scores.java
String value = intent.getStringExtra("somevariable")alter this code like below
Int value = intent.getIntExtra("somevariable")
Sent from my SM-N900 using XDA Free mobile app

As noted by taku_coder you are sending and int then you try to extract a String at least be consistent if you want to send an int then extract as an int on your receiving Activity.
Also i noted that the that you are sending the value to Result Activity shouldnt it be the Scores Activity?
Intent i = new Intent(getApplicationContext(), Result.class);
i.putExtra("somevariable",score);
startActivity(i);
Shouldnt it be like this?
Intent i = new Intent(getApplicationContext(), Scores.class);
i.putExtra("somevariable",score);
startActivity(i);

In Result.java
intent.putExtra("KeyName",X.toString());
you are passing as string, you can get it by using
intent.getextra("KeyName")

Intent i = new Intent(getApplicationContext(), Result.class);
i.putExtra("somevariable",score);
startActivity(i);
It seems to be the code above in OnCreate() method of Result make recursive creation of Result class.

Pass variable from one activity to another

I want to show the result activity on the end of the quiz which is working. And then show the scores activity on press of a button on the main activity
Advice I got is to Create a listener for the scores button on Main Activity and add code to launch the Scores Activity with an intent where you pass the score. And then retrieve the bundle on the onCreate method on your ScoresActivity. Can someone help me on this please regarding the code.
MainActivity:
Code:
package app.mobiledevicesecurity;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends ActionBarActivity {
DatabaseHelper myDb;
private static Button readbtn;
private static Button quizbtn;
private static Button scoresbtn;
private static Button settingsbtn;
private static Button helpbtn;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myDb = new DatabaseHelper(this);
myDb.insertData();
OnClickReadButtonListener();
OnClickQuizButtonListener();
OnClickScoresButtonListener();
OnClickSettingsButtonListener();
OnClickHelpButtonListener();
}
public void OnClickReadButtonListener() {
readbtn = (Button) findViewById(R.id.readbutton);
readbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("app.mobiledevicesecurity.Read_Category");
startActivity(intent);
}
}
);
}
public void OnClickQuizButtonListener() {
quizbtn = (Button) findViewById(R.id.quizbutton);
quizbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("app.mobiledevicesecurity.Quiz");
startActivity(intent);
}
}
);
}
public void OnClickScoresButtonListener() {
scoresbtn = (Button) findViewById(R.id.scoresbutton);
scoresbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("app.mobiledevicesecurity.Scores");
startActivity(intent);
}
}
);
}
public void OnClickSettingsButtonListener() {
settingsbtn = (Button) findViewById(R.id.settingsbutton);
settingsbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("app.mobiledevicesecurity.Settings");
startActivity(intent);
}
}
);
}
public void OnClickHelpButtonListener() {
helpbtn = (Button) findViewById(R.id.helpbutton);
helpbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("app.mobiledevicesecurity.Help");
startActivity(intent);
}
}
);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Result:
Code:
package app.mobiledevicesecurity;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class Result extends Activity {
private static Button playbtn;
private static Button menubutton;
int score;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_result);
OnClickPlayButtonListener();
OnClickMenuButtonListener();
TextView textResult = (TextView) findViewById(R.id.textResult);
Bundle b = getIntent().getExtras();
score = b.getInt("score");
textResult.setText("You scored" + " " + score + " for the quiz.");
}
public void getScore()
{
Intent intent2 = new Intent(Result.this,
Scores.class);
Bundle bun = new Bundle();
bun.putInt("score", score);
intent2.putExtras(bun);
startActivity(intent2);
finish();
}
public void OnClickPlayButtonListener() {
playbtn = (Button) findViewById(R.id.btn);
playbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("app.mobiledevicesecurity.Quiz");
startActivity(intent);
}
}
);
}
public void OnClickMenuButtonListener() {
menubutton = (Button) findViewById(R.id.menubtn);
menubutton.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(getApplicationContext(), MainActivity.class);
startActivity(intent);
}
}
);
}
}
Scores:
Code:
package app.mobiledevicesecurity;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.content.Intent;
public class Scores extends ActionBarActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_scores);
Result res = new Result();
res.getScore();
TextView txtScore1 = (TextView) findViewById(R.id.txtScore1);
Bundle bun = getIntent().getExtras();
int score = bun.getInt("score");
txtScore1.setText("Last quiz score:" + " " + score + ".");
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_scores, 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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

You should never create instances of activity with "new" keyword, because Activity is a part of Android ecosystem, not just a java class. So the line with
Code:
new Result();
is wrong. Then, if you want to pass some data from one activity to another when the latter is being opened after click, you need to put you data in the Intent (like you did it right, but in the wrong place in code)
Code:
scoresbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent2 = new Intent(Result.this,
Scores.class);
Bundle bun = new Bundle();
bun.putInt("score", score);
intent2.putExtras(bun);
startActivity(intent2);
}
}
);
That's it, your code on fetching the "score" variable out of Intent in Score activity is seemingly right.

svvorf said:
You should never create instances of activity with "new" keyword, because Activity is a part of Android ecosystem, not just a java class. So the line with
Code:
new Result();
is wrong. Then, if you want to pass some data from one activity to another when the latter is being opened after click, you need to put you data in the Intent (like you did it right, but in the wrong place in code)
Code:
scoresbtn.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent2 = new Intent(Result.this,
Scores.class);
Bundle bun = new Bundle();
bun.putInt("score", score);
intent2.putExtras(bun);
startActivity(intent2);
}
}
);
That's it, your code on fetching the "score" variable out of Intent in Score activity is seemingly right.
Click to expand...
Click to collapse
Can you maybe show me where to put this in my code. And help me with the new Result() part

JSOUP,HtmlParser

Goodmorning ,
I was dabbling with the parser of a web page through Android Studio, the problem is that the code I implemented can't take what i want, I'll explain:
on a website is a web page with the following html:
HTML:
</style>
</head>
<body>
<h1>TITLE PAGE</h1>
<h2><em></em></h2>
<h2>La data prossimae è:</h2>
<p><br />Lunedi 10/10/2016<br />Orario 13.00 - 18.00</p><input type="button" name="chiudi" value="Chiudi" onclick="javascript: self.close();" />
</body>
</html>
With the class JSOUP I'd like to take just the date which is enclosed within <p>, that is, "10/10/2016", is it possible? for now I could only print the page title or the entire text of the page.
here is the class code:
HTML:
package inducesmile.com.androidjsouphtmlparser;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
import java.io.File;
import java.io.IOException;
public class MainActivity extends ActionBarActivity {
private Document htmlDocument;
private String htmlPageUrl = "website";
private TextView parsedHtmlNode;
private String htmlContentInStringFormat;
[user=439709]@override[/user]
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_livepage);
parsedHtmlNode = (TextView)findViewById(R.id.html_content);
Button htmlTitleButton = (Button)findViewById(R.id.button);
htmlTitleButton.setOnClickListener(new View.OnClickListener() {
[user=439709]@override[/user]
public void onClick(View v) {
JsoupAsyncTask jsoupAsyncTask = new JsoupAsyncTask();
jsoupAsyncTask.execute();
}
});
}
[user=439709]@override[/user]
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_livepage, menu);
return true;
}
[user=439709]@override[/user]
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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private class JsoupAsyncTask extends AsyncTask<Void, Void, Void> {
[user=439709]@override[/user]
protected void onPreExecute() {
super.onPreExecute();
}
[user=439709]@override[/user]
protected Void doInBackground(Void... params) {
try {
htmlDocument = Jsoup.connect(htmlPageUrl).get();
htmlContentInStringFormat = htmlDocument.text();
// htmlDocument.title();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
[user=439709]@override[/user]
protected void onPostExecute(Void result) {
parsedHtmlNode.setText(htmlContentInStringFormat);
}
}
}
Thanks to everyone for help!

Application in Android: when I click on the on/off button the application does not work

I am creating a simple application in Android Studio for managing a device connected via wifi using the Volley library.
The app must do this: when you click on the On button the device must turn on and consequently show the image of a light bulb on, while when I click on the Off button the device must turn off and show the image of a light bulb off on the screen . In Postman the interaction with the device works correctly.
When I start the app and click on the on/off button nothing happens, that is, it always shows me an image of an unlit light bulb. The logcat gives me no errors.
By debugging I notice that when the sendAndRequestResponse() method is executed it does not enter the onResponse method but jumps directly to the setRetryPolicy method.
Can you kindly help me? I am a beginner.
MainActivity.java
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.SwitchCompat;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.CompoundButton;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import java.text.BreakIterator;
public class MainActivity extends AppCompatActivity {
private static final String TAG = MainActivity.class.getName();
SwitchCompat switchButton;
LinearLayout imageViewLight;
private RequestQueue mRequestQueue;
TextView buttonState;
private StringRequest mStringRequest;
private String url = "https://192.168.130.13:8081/zeroconf/switch";
@override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
switchButton=findViewById(R.id.switchButton);
imageViewLight=findViewById(R.id.linearL);
TextView buttonState;
buttonState = findViewById(R.id.buttonState);
switchButton.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
sendAndRequestResponse();
}
});
}
private void sendAndRequestResponse() {
mRequestQueue = Volley.newRequestQueue(this);
mStringRequest = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
@override
public void onResponse(String response) {
TextView myTextView;
if (switchButton.isChecked()) {
imageViewLight.setBackgroundResource(R.drawable.light__02);
buttonState.setText("State : ON");
} else {
imageViewLight.setBackgroundResource(R.drawable.light__01);
buttonState.setText("State : OFF");
}
}
}, new Response.ErrorListener() {
@override
public void onErrorResponse(VolleyError error) {
Log.i(TAG,"Error :" + error.toString());
}
});
mStringRequest.setRetryPolicy(new RetryPolicy() {
@override
public int getCurrentTimeout() {
return 50000;
}
@override
public int getCurrentRetryCount() {
return 50000;
}
@override
public void retry(VolleyError error) throws VolleyError {
}
});
mRequestQueue.add(mStringRequest);
}
}