IT 372 - Quizzes

* = correct answer

Quiz questions and answers will be posted after each
quiz closes.

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Quiz 1. Closed Apr 14.

1. If the package name of an Android Studio project is 
   it372.proj1,  where is the Java file MainActivity.java 
   located?
   a. app/main/src/java
   b. app/main/src/java/it372/Proj1
   c. app/src/main/java
  *d. app/src/main/java/it372/Proj1

2. Where is the layout file activity_main.xml located within 
   the app folder of an Android app?
   a. app/main/src/res/values/layout
  *b. app/src/main/res/layout
   c. app/src/main/res/values/layout
   d. app/src/main/java/layout

3. What is the current version of Android Studio?
   a. Bumblebee       b. Electric Eel
  *c. Iguana          d. Hedgehog

4. Which tool in Android Studio is used to download 
   and install virtual device drivers? 
   The ____________ Manager.
   a. Activity    b. Device     c. SDK     d. Resource

5. Which attribute do you add to the TextView element 
   in the layout file to set the font color to maroon?
   a. android:font-color="#0080FF"
   b. android:fontColor="#800000"
   c. android:text-color="#0080FF"
  *d. android:textColor="#800000"

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Quiz 2. Closed Apr 21.

1. Which Android MainActivity method is roughly 
   equivalent to the main method of a traditional 
   Java class?
   a. MainActivity       *b. onCreate
   b. onStartUp           d. startUp

2. Which statement in MainActivity.java sets the 
   layout as activity_main.xml for the app?
  *a. setContentView(R.layout.activity_main);
   b. setContentView(R.layout.main);
   c. setLayout(R.layout.activity_main);
   d. setLayout(R.layout.main);

3. Which attribute correctly defines the id of a TextView 
   widget as txt_age?
   a. android:id="+id/txt_age"
   b. android:id="@id/txt_age"
   c. android:id="@+id/txt_age"
  *d. android:id="age"

4. Which statement defines the XML namespace prefix android?
   a. android="https://schemas.android.com/apk/res/android"
   b. android:xmlns="https://schemas.android.com/apk/res/android"
   c. namespace:android="https://schemas.android.com/apk/res/android"
   d. xmlns:android="https://schemas.android.com/apk/res/android"

5. In the strings.xml resource file, how do you define a string 
   with the name "pred1" and the value "It is certain."?
   a. <string name=pred1>"It is certain."</string>
  *b. <string name="pred1">It is certain.</string>
   c. <string name=pred1 It is certain. />
   d. <string name="pred1" value="It is certain." />

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Quiz 3. Closed Apr 28.

1. A widget of which class allows the user to enter text 
   into the widget.
  *a. EditText   b. EditView   c. TextField   d. TextView

2. If w1 is a CheckBox or RadioButton widget, which method 
   call returns true if the widget is  checked.
   a. chk1.checked            *b. chk1.isChecked( )
   b. chk1.isChecked(true);    d. chk1.getChecked(true);

3. The Elvis operator (also known as the tertiary conditional 
   operator) consists of which two symbols?
   a. ? =       b. ? >       *c. ? :       d. < ?

4. From the ArrayList collection dice, which statement obtains 
   the value with index 1?
   a. int item = col[1];         *b. int item = col.get(1);
   b. int item = col.get[1];      d. int item = col.getItem[1];

5. Which method is required in an Android Activity class?
  *a. onCreate     b. onDestroy    c. onResume    d. onStart

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Quiz 4. Closed May 5.

1. Which of the following MainActivity.java statements changes the 
   background color of the ImageView with id img_color to silver? 
   The ImageView widget is defined like this:
   ImageView imgColor = findViewById(R.id.img_color);
   a. layout1.setBackgroundColor(0xFFC0C0C0); 
   b. layout1.setBackgroundColor(Color.silver);
   c. layout1.setBackgroundColor(Color.parseColor("#FFC0C0C0");
   d. layout1.setBackgroundColor(R.color.silver);

2. What is the first event that occurs in the Activity life cycle 
   when an app is launched?
  *a. ON_CREATE    b. ON_PAUSE     c. ON_RESUME     d. ON_START

3. Which event occurs when the app is moved into the background?
   a. ON_CREATE    *b. ON_PAUSE     c. ON_RESUME    d. ON_SET_BACKGROUND

4. Which View method can be used to attach a View.OnLongClickListener 
   object or a lambda method to a widget?
   a. addEventListener          b. attachClickListener
   c. onLongClick              *d. setOnLongClickListener

5. An object from which class is used to save data from an activity before 
   it is destroyed so that it can be restored when the activity is recreated, 
   for example, when the device is rotated?
   a. Adapter      *b. Bundle      c. HashMap      d. Intent

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Quiz 5. Closed May 12.

1. An object from which class is used to create and start a 
   new activity?
   a. Bundle     b. HashMap    *c. Intent     d. StartActivity

2. Which Java class has an append method?
   a. ArrayList    b. Integer     c. String    *d. StringBuilder

3. Which ActivityMain.java statement changes the background color 
   of the linear layout to blue? The layout object is obtained like this:
   LinearLayout layout1 = findViewById(R.id.main);
   a. layout1.setBackgroundColor(0xFF0000FF);
   b. layout1.setBackgroundColor(Color.blue);
   c.  layout1.setBackgroundColor(Color.parseColor("#FF0000FF"));
   d. layout1.setBackgroundColor(R.color.blue);

4. The Design Editor is used with a ConstraintLayout to position 
   a Button widget below a TextView widget with id txt_name. What 
   does this constraint look like in the XML layout file?
   a. android.layout_constraint="@+id/txt_name"
   b. android.layout_constraintTop_toBottomOf="@+id/txt_name"
  *c. app.layout_constraintTop_toBottomOf="@+id/txt_name"
   d. app.layout_margin="@+id/txt_name"

5. These Java statements add a click event listener to a 
   CheckBox widget using Method 3 (anonymous class). 

   checkbox1.setOnCheckedChangeListener(
       new CompoundButton.OnCheckedChangeListener( ) {
           @Override
           public void onCheckedChanged(
               CompoundButton compoundButton, boolean b) {
                   Toast t = Toast.makeText(getApplicationContext( ),
                       "Checkbox is " +
                       (compoundButton.isChecked( ) ? "checked" : "unchecked"),
                       Toast.LENGTH_LONG);
                   t.show( );
               }
  });
  Which method call adds a CheckedChanged eventlistener using Method 4 
  (lambda function)?

// a.
checkbox1.setOnCheckedChangeListener(
    checkbox1, b -> {
    Toast t = Toast.makeText(getApplicationContext( ),
        "Checkbox is " + (compoundButton.isChecked( ) ?
            "checked" : "unchecked"),
            Toast.LENGTH_LONG);
        t.show( );
});

// b.
checkbox1.setOnCheckedChangeListener(
    (checkbox1, b) -> {
    Toast t = Toast.makeText(getApplicationContext( ),
        "Checkbox is " + (compoundButton.isChecked( ) ?
            "checked" : "unchecked"),
            Toast.LENGTH_LONG);
        t.show( );
});

// c.
checkbox1.setOnCheckedChangeListener(
    compoundButton, b -> {
        Toast t = Toast.makeText(getApplicationContext( ),
            "Checkbox is " + (b ? "checked" : "unchecked"),
             Toast.LENGTH_LONG);
        t.show( );
});

// *d.
checkbox1.setOnCheckedChangeListener(
    (cb, b) -> {
        Toast t = Toast.makeText(getApplicationContext( ),
            "Checkbox is " + (b ? "checked" : "unchecked"),
            Toast.LENGTH_LONG);
        t.show( );
});

Save Time

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Quiz 6. Closed May 19.

1. Find the UTF-8 encoding for the á character (a with acute 
   accent), which has the hex Unicode code E1. This UTF-8 
   encoding requires two bytes.
   a. 00E1    b. 03AE     *c. C3A1     d. C3E1

2. Find the UTF-8 encoding for the ♯ character (sharp sign 
   from music), which has the hex Unicode code 266F. This UTF-8 
   encoding requires three bytes.
   a. 00266F     b. C2266F      c. C2D9A7     *d. E299AF

3. For an Android drawing in a view, an object of which class 
   is used to specify the color and stroke width for drawing an item?
   a. Color      b. Graphics     *c. Paint     d. StrokeWidth

4. The class MyView is a derived class of View. Which method of 
   the View class is overridden to contain the code for drawing 
   in a MyView object?
   a. draw      *b. onDraw     c. onPaint     d. paint

5. What is the file extension of an Android executable file?
   a. .class     *b. .dex     c. .java     d. .kt

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Quiz 7. Closed May 26.

1. An object of which class is used to call drawing methods 
   in a View onDraw method?
  *a. Canvas     b. Graphics     c. Panel     d. View

2. An object of which class contains information about a touch 
   event that occurred, which was detected by a touch event handler?  
   For example, this object contains the x and y location of the 
   touch and whether the touch was touch down, touch up, or touch move.
   a. ClickEvent  *b. MotionEvent   c. MouseMoveEvent   d. TouchEvent

3. To read from a text file named points.txt in the folder 
   app/src/main/res/raw, an object from which class is used?
   a. File     b. FileStream    *c. InputStream     d. String

4. What is the file extension of an Android app packaged for distribution?
  *a .apk       b. .dex       c. .jar      d. .pak

5. Which Android Studio tool is used to view folders and files on a 
   Virtual Device?
   a. Chrome Browser       *b. Device File Explorer
   c. Logcat Window         d. Windows File Explorer


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Quiz 8. Closed June 2.

1. If dbh is an object of a class derived from the base class 
   SQLiteOpenHelper, which method call returns an SQLiteDatabase 
   object representing a database that can be modified?
   a. dbh.getDatabase(  );       b. dbh.getDatabase(true);
   c. dbh.getDb(  ) ;           *d. dbh.getWritableDatabase(  );

2. In an Android app, an object of which class contains data to 
   be inserted as an SQLite table row.
  *a. ContentValues     b. Point    c. RowValues     d. TableRow

3. An object of which class contains the results of a query of an 
   SQLite table?
  *a. Cursor      b. QueryResult      c. ResultSet    d. TableQuery

4. Which Kotlin statement is a translation of this Java statement?
   int count = 359;
   a. count = 359;              *b. var count = 359
   c. var count: int = 359       d. var count = new Int(359)

5. What is the header of a Kotlin toString method?
  *a. override fun toString( ) : String {

   b. @Override
      fun toString( ) : String {
   c. Override
      fun toString( ) : str {
   d. @Override
      String : toString(

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Quiz 8. Closed June 11.

1. Which keyword is used to create a Kotlin function 
   or method?
   a. def     *b. fun     c. function
   d. No specific keyword is used.

2. Which keyword or token denotes that a Kotlin class 
   is inheriting from a base class?
  *a. :    b. ->    c. extends    d. inherits

3. Which keyword or token is used in a Kotlin method 
   to indicate that the method overrides a method from 
   an interface.
  *a. :    b. @Override    c. override    d. Overrides

4. Which keyword or token indicates that a Kotlin 
   derived class is available to be used as a base class.
   a. :    b. ::    c. inheritable    *d.open

5. In a Jetpack Compose app, the MainActivity class 
   does not inherit from AppCompatActivity, it inherits 
   from _____________ .
   a. Activity             b. Any   
   c. CompatActivity      *d. ComponentActivity


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