Develop Reference

My button code keeps giving me error in Android Studio

So I cant figure out how to get my button working I am having some problems in ANdroid Studio I am a very begginer so please be patient with me. Do you guys have any idea. I know I am doing something wrong but I cant figure out what it is.
thanks
package com.example.moemo.myapplication;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import java.util.concurrent.Future;
public class MainActivity extends AppCompatActivity {
private Button button4;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
button = (Button) findViewById(R.id.button4);
button.setOnClickListner(new View.OnClickListener() {
#Override
public void onClick(View v) {
openFutureEvents();
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
public void openFutureEvents() {
Intent intent = new Intent( this, FutureEvents.class )
startFutureEvents();
})
#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);
}
}
private void startFutureEvents() {
}

Since there are no error logs, somethings that I see wrong straight away:
You have your setContentView() inside your button onClickListener and alot of other code that shouldn't be inside onClickListener
Change your code as below:
public class MainActivity extends AppCompatActivity {
private Button button4;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button = (Button) findViewById(R.id.button4);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
button.setOnClickListner(new View.OnClickListener() {
#Override
public void onClick(View v) {
openFutureEvents();
});
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});

Copy the following code and run!
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import java.util.concurrent.Future;
public class MainActivity extends AppCompatActivity {
private Button button4;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
button = (Button) findViewById(R.id.button4);
button.setOnClickListner(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(new Intent(FutureEvents.class);
}
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
#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);
}
}
What I have corrected is,
(1) removed unnecessary functions, openFutureEvents() & startFutureEvents().
(2) added startActivity() to call Activity.
Keep note that if you want to start an activity, you have to call startActivity(new Intent(YourActivity.class);

Try this one
public class MainActivity extends AppCompatActivity {
private Button button4;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
button4 = (Button) findViewById(R.id.button4);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
button4.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
openFutureEvents();
}
});
}
#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);
}
public void openFutureEvents() {
Intent intent = new Intent(this, FutureEvents.class);
startActivity(intent);
}
private void startFutureEvents() {}
}

within your onCreate() method start by invoking
super.onCreate() method of the parent class
then setContentView(R.layout.activity_main); to inflate the layout
get reference to the view widgets (button,...)
button = (Button) findViewById(R.id.button);
then your event handlers... CHEERS

package com.example.moemo.myapplication;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends AppCompatActivity {
private Button button;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button = (Button) findViewById(R.id.button);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
button.setOnClickListner(new View.OnClickListener() {
#Override
public void onClick(View v) {
openFutureEvents();
});
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
#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);
}
}

Android create clickable email link programmatically

I want to create an email link in an Android app.
If I do it this way:
<TextView
android:text="xxxx#yyyy.zz"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingTop="10dp"
android:autoLink="email"/>
Then it works as it should.
I do, however, want to do it in code. The following example is a new Android project in Android Studio with a basic activity. I have added the marked code and added the id "mytest" to the auto-generated layout.
package com.example.bjursus.myapplication;
import android.content.Intent;
import android.os.Bundle;
import android.support.constraint.ConstraintLayout;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.text.util.Linkify;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.view.ViewGroup;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Added code - start
getIntent().setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
ConstraintLayout clo = (ConstraintLayout) findViewById(R.id.mytest);
TextView tv = new TextView(getApplicationContext());
tv.setText("zxxx#yyyy.zz");
Linkify.addLinks(tv, Linkify.EMAIL_ADDRESSES);
tv.setLinksClickable(true);
clo.addView(tv);
// Added code - end
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
#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);
}
}
This will give me the email link, but when I click it I get this exception:
AndroidRuntimeException: Calling startActivity() from outside of an Activity context requires the FLAG_ACTIVITY_NEW_TASK flag. Is this really what you want?
Any suggestions?

Simply add this to the code
getIntent().setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
This will tell your activity it is okay to start a new task.

how to change the icon color of search view

Anyone help me i want to change the default icon color of search view.i want to open the search item in this activity and get the result in another activity.I am using android.support.v7.widget.SearchView in my menu class Iwant to set the icon but its not showing when i run the code.
package com.example.abc.fullvolleysearch;
import android.app.SearchManager;
import android.content.Context;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.MenuInflater;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.app.SearchManager;
import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.SearchView;
import android.view.Menu;
import android.view.MenuInflater;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
MenuInflater inflater = getMenuInflater();
// Inflate menu to add items to action bar if it is present.
inflater.inflate(R.menu.menu_main, menu);
// Associate searchable configuration with the SearchView
/* SearchManager searchManager =
(SearchManager) getSystemService(Context.SEARCH_SERVICE);
SearchView searchView =
(SearchView) menu.findItem(R.id.menu_search).getActionView();
searchView.setSearchableInfo(
searchManager.getSearchableInfo(getComponentName()));*/
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);
}
}
Here is my menu xml item
<item
android:id="#+id/menu_search"
android:title="#string/menu_search"
appcompat:actionViewClass="android.support.v7.widget.SearchView"
appcompat:showAsAction="always"/>

For Lollipop and above versions place the below code in onCreateOptionsMenu() before return statement
SearchView searchView = (SearchView) MenuItemCompat.getActionView(menu.findItem(R.id.action_search));
ImageView searchButton = (ImageView) searchView.findViewById(android.support.v7.appcompat.R.id.search_button);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
searchButton.setImageTintList(ColorStateList.valueOf(getResources().getColor(R.color.yourDesiredColor)));
}
might be useful for someone.

Add This as Your Menu Item
android:icon="#drawable/search"

Android Studio MainActivity.java:: error: ';' expected

I am new to Android development, When Android Studio in "MainActivity" class is compiled I get the following error
I have pasted the error log below:
:\Users\kanak\AndroidStudioProjects\SelfDistructText\app\src\main\java\com\example\kanak\selfdistructtext\MainActivity.java:61: error: ';' expected
public boolean onCreateOptionsMenu(Menu menu){
^
C:\Users\kanak\AndroidStudioProjects\SelfDistructText\app\src\main\java\com\example\kanak\selfdistructtext\MainActivity.java:61: error: ';' expected
public boolean onCreateOptionsMenu(Menu menu){
^
C:\Users\kanak\AndroidStudioProjects\SelfDistructText\app\src\main\java\com\example\kanak\selfdistructtext\MainActivity.java:69: error: ';' expected
public boolean onOptionsItemSelected (MenuItem item){
^
C:\Users\kanak\AndroidStudioProjects\SelfDistructText\app\src\main\java\com\example\kanak\selfdistructtext\MainActivity.java:69: error: ';' expected
public boolean onOptionsItemSelected (MenuItem item){
I have pasted my MainActivity Class code below:
enter code here
package com.example.kanak.selfdistructtext;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.app.ActionBar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import com.parse.Parse;
import com.parse.ParseAnalytics;
import com.parse.ParseObject;
import com.parse.ParseUser;
public class MainActivity extends AppCompatActivity{`enter code here`
public static final String TAG = MainActivity.class.getSimpleName();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
// Parase Analytice
ParseAnalytics.trackAppOpenedInBackground(getIntent());
ParseUser currentUser = ParseUser.getCurrentUser();
if (currentUser == null) {
Intent intent = new Intent(this, LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
} else {
Log.i(TAG, currentUser.getUsername());
}
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
#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);
}
}
}

Replace your code with the following code:
public class MainActivity extends AppCompatActivity{
public static final String TAG = MainActivity.class.getSimpleName();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
// Parase Analytice
ParseAnalytics.trackAppOpenedInBackground(getIntent());
ParseUser currentUser = ParseUser.getCurrentUser();
if (currentUser == null) {
Intent intent = new Intent(this, LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
} else {
Log.i(TAG, currentUser.getUsername());
}
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
#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);
}
}
}

Functions are not closed properly.
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.app.ActionBar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import com.parse.Parse;
import com.parse.ParseAnalytics;
import com.parse.ParseObject;
import com.parse.ParseUser;
public class MainActivity extends AppCompatActivity{
public static final String TAG = MainActivity.class.getSimpleName();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
// Parase Analytice
ParseAnalytics.trackAppOpenedInBackground(getIntent());
ParseUser currentUser = ParseUser.getCurrentUser();
if (currentUser == null) {
Intent intent = new Intent(this, LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
} else {
Log.i(TAG, currentUser.getUsername());
}
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}//CLOSE ONCREATE here
#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);
}
}

replace
#Override
public boolean onCreateOptionsMenu(Menu menu){
with
}
#Override
public boolean onCreateOptionsMenu(Menu menu){
and replace
**public boolean onOptionsItemSelected (MenuItem item){**
with
public boolean onOptionsItemSelected (MenuItem item){

setOnCheckedChangeListener(this) error

I'm beginner in android.
I read some books. I create checkbox
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
public class MainActivity extends AppCompatActivity implements OnCheckedChangeListener {
CheckBox cb;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
cb = (CheckBox) findViewById(R.id.mycheckbox);
cb.setOnCheckedChangeListener(this);
}
});
}
#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);
}
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
cb.setText("Checked");
} else {
cb.setText("UnCheck");
}
}
}
When use cb.setOnCheckedChangeListener(this); android studio error:
setOnCheckedChangeListener(android.widget.CompoundButton.OnCheckedChangeListener) in CompoundButton cannot be applied (anonymous android.view.View.onClickListener)
If i change code such as:
cb.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
//do stuff
}
});
Then ok
Can you help me. i want to use "this".

Use MainActivity.this instead of this :
cb.setOnCheckedChangeListener(MainActivity.this);
Because in current code this refer to the Button onClick method context instead of MainActivity class in which OnCheckedChangeListener interface in implemented.