How to get information from a customized ListView in Android

Question

I have a ListView that I have customized to display information gathered from an SQLite database. Each item is a represented using a CardView widget containing TextViews. I have set the ListView property in the .xml file to:

android:choiceMode="singleChoice"

allowing the user to make a selection from the list.

When the user clicks the floating action button, I want to be able to take information displayed in one of the TextViews of the CardView selected in the ListView.

I have looked at other questions on the topic and they suggest using the onClick method, but I do not understand how that would work because I do not want to retrieve the information when the user makes the selection from the list. Rather, I want the information when they have selected the floating action button.

Here is part of my Activity code:

public class SetViewerActivity extends AppCompatActivity {

private static final String TAG = "SetViewerActivity";
private boolean fabState;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // set contents of activity
    setContentView(R.layout.activity_set_viewer);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    // set action for main floating action button
    FloatingActionButton fab = (FloatingActionButton) 
 findViewById(R.id.fab);
    fabState = false;
    fab.setOnClickListener(new View.OnClickListener() {
        // get set info and edit in new Activity
        @Override
        public void onClick(View view) {
            editSelectedSet(view);
        }
    });

    // set up list view and populate with custom set info from database
    SQLiteDatabase db = new MemCardSQLiteHelper(this).getReadableDatabase();
    Cursor cursor = db.rawQuery(MemCardDbContract.Sets.SELECT_ALL_SETS, 
null);
    ListView lvSets = (ListView) findViewById(R.id.listViewSets);
    SetViewAdapter adapter = new SetViewAdapter(this, cursor);
    lvSets.setAdapter(adapter);
}

private void editSelectedSet(View view) {

    // HOW DO I FIND THE SET INFORMATION HERE ??        

    // start activity with selected set information for editing
    Intent intent = new Intent(this, CreateNewSet.class);
    intent.putExtra(MainActivity.CREATE_SET_NUM, selectedSet);
    startActivity(intent);
}
}

and here is my xml for each ListView item:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dp">
<android.support.v7.widget.CardView
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    app:cardCornerRadius="4dp"
    app:cardElevation="2dp"
    app:contentPadding="2dp">
    <android.support.constraint.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <TextView
            android:id="@+id/textViewName"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginRight="8dp"
            android:layout_marginTop="8dp"
            android:layout_weight="1"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent" />
        <TextView
            android:id="@+id/textViewAmount"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginRight="8dp"
            android:layout_marginTop="8dp"
            android:layout_weight="1"
            app:layout_constraintHorizontal_bias="0.0"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/textViewName" />
        <TextView
            android:id="@+id/textViewColour"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginRight="8dp"
            android:layout_marginTop="10dp"
            android:layout_weight="1"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintHorizontal_bias="0.0"
            app:layout_constraintTop_toBottomOf="@+id/textViewAmount" />
        <TextView
            android:id="@+id/textViewSetId"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:visibility="gone" />
    </android.support.constraint.ConstraintLayout>
</android.support.v7.widget.CardView>
</LinearLayout>

Answer 1

You can assign an onClick on each item and when an item is selected (clicked) than you can save the data as a field member. Then read the data where ever you want.