title: call another activity after the click on the menu
body: <p>I have a menu and want to call the next activity , so that the user can calculate and then want to return the next page or the home page , but do not know how to do this ... Ja tried in many ways , but not the right or when it works on another page disappear all anetriores menus , leaving you stuck only that activity.</p>
  
  <p><em>I am new to programming and especially on android.</em></p>
  
  <p><strong>MainActivity:</strong></p>
  
  <pre><code>@SuppressWarnings("StatementWithEmptyBody")
      @Override
      public boolean onNavigationItemSelected(MenuItem item) {
          // Handle navigation view item clicks here.
          int id = item.getItemId();
  
          if (id == R.id.nav_camera) {
              //I want to call the page " calculations" here.
  
          } else if (id == R.id.nav_gallery) {
  
      }
  
          DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
          drawer.closeDrawer(GravityCompat.START);
          return true;
      }
  }
  </code></pre>
  
  <p><strong>android_manifest.xml:</strong></p>
  
  <pre><code>    &lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.example.stark.hello_world"&gt;
  
      &lt;application
          android:allowBackup="true"
          android:icon="@mipmap/ic_launcher"
          android:label="@string/app_name"
          android:supportsRtl="true"
          android:theme="@style/AppTheme"&gt;
          &lt;activity
              android:name=".Splashscreen"
              android:label="@string/app_name"&gt;
              &lt;intent-filter&gt;
                  &lt;action android:name="android.intent.action.MAIN" /&gt;
  
                  &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
              &lt;/intent-filter&gt;
          &lt;/activity&gt;
          &lt;activity
              android:name=".MainActivity"
              android:label="@string/app_name"
              android:theme="@style/AppTheme.NoActionBar"&gt;
              &lt;intent-filter&gt;
                  &lt;action android:name="android.intent.action.MAIN" /&gt;
                  &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
              &lt;/intent-filter&gt;
          &lt;/activity&gt;
  
          &lt;activity
              android:name=".Calculos"
              android:label="@string/action_help"
              android:parentActivityName=".MainActivity" /&gt;
  
      &lt;/application&gt;
  
  &lt;/manifest&gt;
  </code></pre>
  
  <p><strong>calculos.xml</strong></p>
  
  <pre><code>&lt;RelativeLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:paddingLeft="4dp"
      android:paddingRight="4dp"
      android:paddingTop="4dp"
      android:paddingBottom="4dp"
      tools:context=".MainActivity"
      android:background="#ff0fffab"&gt;
  
  
      &lt;TextView
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:textAppearance="?android:attr/textAppearanceLarge"
          android:text="SEM"
          android:id="@+id/textView"
          android:layout_centerVertical="true"
          android:layout_centerHorizontal="true"
          android:textSize="@dimen/abc_text_size_display_3_material"
          android:textColor="#ffffffff" /&gt;
  
      &lt;EditText
          android:id="@+id/email_address"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
          android:inputType="number" /&gt;
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/uuy69.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uuy69.jpg" alt="app"></a></p>