Practice T

Question 1

Is this legal XML (Imagine the <>s)

LinearLayout Button / Button /Button /LinearLayout

Answer 1

Yes

Question 2

What is the return type of the function findViewBydId(int id)

Answer 2

View

Question 3

If you declare an XML tag <androidx.appcompat.widget.Toolbar>, is this the normal android libraries or the AppCompat libraries?</androidx.appcompat.widget.Toolbar>

Answer 3

AppCompat libraries

Question 4

T/F - If you are using the normal Android libraries, you can call setSupportActionBar() to load a toolbar

Answer 4

False.

setSupportActionBar did not exist pre-androidx. You would use setActionBar

Question 5

What function would you call to set the view of a Dialog box?

Answer 5

setView

Question 6

For a Checkbox or switch widget, what function do you call to listen for when the user clicks on it?

Answer 6

setOnCheckedChangedListener

Question 7

What is the default orientation of LinearLayout?

Answer 7

Horizontal

Question 8

What function do you call on the adapter to redraw the reyclerView when data has been added or removed?

Answer 8

notifyDatasetChanged()

Question 9

What should the function getView(int, position, View old, ViewGroup parent) use to load a view?

Answer 9

LayoutInflater

Question 10

if you call getWriteableDatabase() from an SQLiteOpenHelper object and the older version is 1.9 and the new version is 2, what function will get called? What if they’re the same version?

Answer 10

Different: getUpgrade()

Same: Nothing will get called

Question 11

What function do you call to start an AyncTask?

Answer 11

execute()

Question 12

If you go to another Activity using startActivity(), does onActivityReult() get called when the next activity terminates?

Answer 12

No

Question 13

If you create a subclass of AsyncTask<String, Integer, Double>, what is the parameter type of the doInBackground(??) function?

Answer 13

String

Question 14

AsyncTask<Params, Progress, Result>

How do these 3 sections relate to doInBackground() ?

Answer 14

Params - type of input parameters to pass to doInBackground

Progress - The type of values that represent progress updates

Result - the type returned as a result from doInBackground

Question 15

What do you call on a recyclerView to listen for users selecting something from the list?

Answer 15

setOnItemClickListener()

Question 16

What function causes a recyclerView to draw items? (First time)

Answer 16

setAdapter()

Question 17

Which of these is not a type of Fragment Transaction?

delete

add

replace

remove

Answer 17

delete

Question 18

If we set MenuItem to ShowAsAction=”always”, what parameter gets used?

Answer 18

icon

Question 19

What does the insert function return?

Answer 19

The id of the row where the record was inserted

Question 20

T/F - You can open a connection to a web server on the GUI thread

Answer 20

False

Question 21

If a JSON object has the attribute “value”:24.5, what function would you call to retrieve the data?

Answer 21

getDouble(“value”);

Question 22

If there is a tag: <-car brand=”ford” /->, what function do you call to read what brand is written in the tag?

Answer 22

getAttributeValue(null, “brand”)

Question 23

What does the update() function return?

Answer 23

The number of rows updated

Question 24

If you see the message “Unfortunately IainsAndroidLabs stopped” where do you look for more info?

Answer 24

LogCat tab

Question 25

IF you click on an item in the NavigationView, what function gets called?

Answer 25

onNavigationItemSelected

Question 26

These 2 lines of code are in the onCreate() function of an Activity whose layout is called saveLayout.xml
Button saveButton = (Button)findViewById(R.id.SaveButton);
setContentView(R.layout.saveLayout)

What is the value of the variable saveButton now?

Answer 26

null

Question 27

What function do you call to stop an Activity, and go to the previous Activity

Answer 27

finish()

Question 28

What function do you call to run a fragment transaction?

Answer 28

commit()