What do you want from Room when you create a DAO method and annotate it with @Delete?Example:@Daopublic interface MyDao { @Deletepublic void deleteUsers(User... users); }

Room removes a set of entities, given as parameters, from the database. It uses the primary keys to find the entities to delete.

Room generates an implementation that inserts all parameters into the database in a single transaction.

Room modifies a set of entities, given as parameters, in the database. It uses a query that matches against the primary key of each entity.

Room removes a set of entities, given as parameters, from the database. It uses the primary keys to find the entities to delete.

In Android 8.0, API level 26, some APIs regarding notification behaviors were moved from Notification to NotificationChannel. For example, what should we use instead of NotificationCompat.Builder.setPriority() for Android 8.0 and higher?

NotificationChannel.setImportance()

NotificationChannel.setPriority()

NotificationChannel.setImportance()

NotificationCompat.Builder.setImportance()

When scheduling unique work, you must tell WorkManager what action to take when there is a conflict. You do this by passing an enum when enquing the work.For one-time work, you provide an ExistingWorkPolicy, which supports some options for handling the conflict. (Choose four.)

REPLACE (existing work with the new work. This option cancels the existing work)

KEEP (existing work and ignore the new work)

APPEND (the new work to the end of the existing work. This policy will cause your new work to be chained to the existing work, running after the existing work finishes)

APPEND_OR_REPLACE (functions similarly to APPEND, except that it is not dependent on prerequisite work status. If the existing work is CANCELLED or FAILED, the new work still runs)

REPLACE (existing work with the new work. This option cancels the existing work)

KEEP (existing work and ignore the new work)

APPEND (the new work to the end of the existing work. This policy will cause your new work to be chained to the existing work, running after the existing work finishes)

APPEND_OR_REPLACE (functions similarly to APPEND, except that it is not dependent on prerequisite work status. If the existing work is CANCELLED or FAILED, the new work still runs)

APPEND_OR_KEEP (functions similarly to APPEND, except that it is not dependent on prerequisite work status. If the existing work is CANCELLED or FAILED, the new work still not runs)

APPEND_AND_RUN (functions similarly to APPEND, except that it is not dependent on prerequisite work status. If the existing work is PAUSED, the new work still runs)

DESTROY (if any work exists, the new work will be ignored)

APPEND_OR_DESTROY (if no any work exists, the new work will be ignored)

If you are working with a Builder that creates a PeriodicWorkRequest to run periodically once within the flex period of every interval period. What statement is correct?

The repeat interval must be greater than or equal to PeriodicWorkRequest.MIN_PERIODIC_INTERVAL_MILLIS and the flex interval must be greater than or equal to PeriodicWorkRequest.MIN_PERIODIC_FLEX_MILLIS.

The repeat interval must be greater than PeriodicWorkRequest.MIN_PERIODIC_INTERVAL_MILLIS and the flex interval must be greater than PeriodicWorkRequest.MIN_PERIODIC_FLEX_MILLIS.

The repeat interval must be lower than or equal to PeriodicWorkRequest.MIN_PERIODIC_INTERVAL_MILLIS and the flex interval must be lower than or equal to PeriodicWorkRequest.MIN_PERIODIC_FLEX_MILLIS.

The repeat interval must be greater than or equal to PeriodicWorkRequest.MIN_PERIODIC_INTERVAL_MILLIS and the flex interval can be anything in relation to PeriodicWorkRequest.MIN_PERIODIC_FLEX_MILLIS.

The repeat interval must be greater than or equal to PeriodicWorkRequest.MIN_PERIODIC_INTERVAL_MILLIS and the flex interval must be greater than or equal to PeriodicWorkRequest.MIN_PERIODIC_FLEX_MILLIS.

If constant LENGTH_INDEFINITE is used as a parameter for the setDuration method in Snackbar, what will happen?

The Snackbar will be displayed from the time that is shown until either it is dismissed, or another Snackbar is shown.

The Snackbar will be displayed for a short period of time.

The Snackbar will be displayed for a long period of time.

The Snackbar will be displayed for a very long period of time.

The Snackbar will be displayed from the time that is shown until either it is dismissed, or another Snackbar is shown.

The constant LENGTH_INDEFINITE is impossible parameter for the setDuration method in Snackbar

If you want get a debuggable APK that people can install without adb, in Android Studio you can:

Select your debug variant and click Build Bundle(s) / APK(s) > Build APK(s).

Click the Run button from toolbar

Select your debug variant and click Analyze APK.

To build a debug APK, you can open a command line and navigate to the root of your project directory. To initiate a debug build, invoke the assembleDebug task:gradlew assembleDebugThis creates an APK named [module_name]-debug.apk in[project_name]/[module_name]/build/outputs/apk/Select correct statements about generated file. (Choose all that apply.)

The file is already signed with the debug key

The file is already aligned with zipalign

You can immediately install this file on a device.

The file is already signed with the debug key

The file is already aligned with zipalign

You can immediately install this file on a device.

Assume that an app includes a default set of graphics and two other sets of graphics, each optimized for a different device setup:res/drawable/Contains default graphics.res/drawable-small-land-stylus/Contains graphics optimized for use with a device that expects input from a stylus and has a QVGA low-density screen in landscape orientation.res/drawable-ja/Contains graphics optimized for use with Japanese.What happens if the app runs on a device that is configured to use Japanese and, at the same time, the device happens to be one that expects input from a stylus and has a QVGA low-density screen in landscape orientation?

Android loads graphics from res/drawable-ja/

Android loads graphics from res/drawable/

Android loads graphics from res/drawable-small-land-stylus/

Android loads graphics from res/drawable-ja/

Assume that you have the following situation:The app code calls for R.string.text_aThree relevant resource files are available:- res/values/strings.xml, which includes text_a in the app's default language, in this case English.- res/values-mcc404/strings.xml, which includes text_a in the app's default language, in this case English.- res/values-hi/strings.xml, which includes text_a in Hindi.The app is running on a device that has the following configuration:- The SIM card is connected to a mobile network in India (MCC 404).- The language is set to Hindi (hi).Which is the correct statement below?

Android loads text_a from res/values-mcc404/strings.xml (in English)

Android loads text_a from res/values/strings.xml (in English)

Android loads text_a from res/values-mcc404/strings.xml (in English)

Android loads text_a from res/values-hi/strings.xml (in Hindi)

What is the placeholder tag <xliff:g> used for?

To mark text that should not be translated.

To raise a translation priority to a higher level

To raise a quantity of translations for the string

To pick up and move sting translation from a different resource file

Choose the most correct statement.

Android is an open source, Linux-based software stack created for a wide array of devices and form factors.

Android is a closed source, Linux-based software stack created for a wide array of devices and form factors.

Android is a closed source, Windows-based software stack created for a wide array of devices and form factors.

Android is an open source, Linux-based software stack created for a wide array of devices and form factors.

Android is an open source software stack created for a highly limited array of devices and form factors.

Select correct statements about Hardware Abstraction Layer (HAL). (Choose two.)

The HAL provides standard interfaces that expose device hardware capabilities to the higher-level Java API framework.

The HAL consists of multiple library modules, each of which implements an interface for a specific type of hardware component, such as the camera or bluetooth module. When a framework API makes a call to access device hardware,the Android system loads the library module for that hardware component.

The HAL provides standard interfaces that expose device hardware capabilities to the higher-level Java API framework.

The HAL function both as apps for users and to provide key capabilities that developers can access from their own app. For example, if your app would like to deliver an SMS message, you don't need to build that functionality yourself -you can instead invoke whichever SMS app is already installed to deliver a message to the recipient you specify

The HAL consists of multiple library modules, each of which implements an interface for a specific type of hardware component, such as the camera or bluetooth module. When a framework API makes a call to access device hardware,the Android system loads the library module for that hardware component.

Using a HAL, not using a Linux kernel, allows Android to take advantage of key security features and allows device manufacturers to develop hardware drivers for a well-known kernel.

Select a correct statement about PagedList.

PagedList is content-immutable. This means that, although new content can be loaded into an instance of PagedList, the loaded items themselves cannot change once loaded.

PagedList is content-mutable. This means that new content can be loaded into an instance of PagedList and the loaded items themselves can change once loaded.

PagedList is content-immutable. This means that, although new content can be loaded into an instance of PagedList, the loaded items themselves cannot change once loaded.

PagedList is content-accidental. This means that new content can be loaded into an instance of PagedList and the loaded items themselves can be changed to accidental values randomly.

If content in a PagedList updates, the PagedListAdapter object receives:

a completely new PagedList that contains the updated information.

only one item from PagedList that contains the updated information.

one or more items from PagedList that contains the updated information.

a completely new PagedList that contains the updated information.

Relative positioning is one of the basic building blocks of creating layouts in ConstraintLayout. Constraints allow you to position a given widget relative to another one. What constraints do not exist?

layout_constraintBaseline_toStartOf

layout_constraintBottom_toBottomOf

layout_constraintBaseline_toBaselineOf

layout_constraintBaseline_toStartOf

Which statement is most true about layout_constraintLeft_toRightOf and layout_constraintStart_toEndOf constraints ?

layout_constraintLeft_toRightOf is equal to layout_constraintStart_toEndOf in case if user choose a language that uses left-to-right (LTR) scripts, such as English or French, for their UI locale

layout_constraintLeft_toRightOf is equal to layout_constraintStart_toEndOf in any case

layout_constraintLeft_toRightOf is equal to layout_constraintStart_toEndOf in case if user choose a language that uses right-to-left (RTL) scripts, such as Arabic or Hebrew, for their UI locale

layout_constraintLeft_toRightOf is equal to layout_constraintStart_toEndOf in case if user choose a language that uses left-to-right (LTR) scripts, such as English or French, for their UI locale

layout_constraintLeft_toRightOf works with horizontal axes and layout_constraintStart_toEndOf works with vertical axes

In application theme style, flag windowNoTitle (<item name="windowNoTitle">) indicates:

whether there should be no title on this window.

whether this window should have an Action Bar in place of the usual title bar.

whether there should be no title on this window.

that this window should not be displayed at all.

whether this is a floating window.

whether this Window is responsible for drawing the background for the system bars.

A content label sometimes depends on information only available at runtime, or the meaning of a View might change over time. For example, a Play button might change to a Pause button during music playback. In these cases, to update the content label at the appropriate time, we can use:

View#setContentDescription(CharSequence contentDescription)

View#setContentDescription(int contentDescriptionResId)

View#setContentLabel(int contentDescriptionResId)

View#setContentDescription(CharSequence contentDescription)

View#setContentLabel(CharSequence contentDescription)

In application theme style, flag windowActionBar (<item name="windowActionBar">) indicates:

whether this window should have an Action Bar in place of the usual title bar.

whether the given application component is available to other applications.

whether action modes should overlay window content when there is not reserved space for their UI (such as an Action Bar).

whether this window's Action Bar should overlay application content.

whether this window should have an Action Bar in place of the usual title bar.

In application theme style, flag windowNoTitle (<item name="windowNoTitle">) indicates:

whether there should be no title on this window.

whether this window should have an Action Bar in place of the usual title bar.

whether there should be no title on this window.

that this window should not be displayed at all.

whether this is a floating window.

whether this Window is responsible for drawing the background for the system bars.

In application theme style, flag windowDrawsSystemBarBackgrounds (<item name="android:windowDrawsSystemBarBackgrounds">) indicates:

whether this Window is responsible for drawing the background for the system bars.

whether this window should have an Action Bar in place of the usual title bar.

whether there should be no title on this window.

that this window should not be displayed at all.

whether this is a floating window.

whether this Window is responsible for drawing the background for the system bars.

In application theme style, value statusBarColor (<item name="android:statusBarColor">) means:

The color for the status bar. If the color is not opaque, consider setting View.SYSTEM_UI_FLAG_LAYOUT_STABLE andView.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN. For this to take effect, the window must be drawing thesystem bar backgrounds with

Color of text (usually same as colorForeground).

Shows a thin line of the specified color between the navigation bar and the app content.For this to take effect, the window must be drawing the system bar backgrounds with R.attr.windowDrawsSystemBarBackgrounds and the navigation bar must not have been requested to be translucent with R.attr.windowTranslucentNavigation. Corresponds to Window.setNavigationBarDividerColor(int).

The color for the status bar. If the color is not opaque, consider setting View.SYSTEM_UI_FLAG_LAYOUT_STABLE andView.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN. For this to take effect, the window must be drawing thesystem bar backgrounds with

attr.windowDrawsSystemBarBackgrounds and the status bar must not have been requested to be translucent with R.attr.windowTranslucentStatus.Corresponds to Window.setStatusBarColor(int).

The color for the navigation bar. If the color is not opaque, consider setting View.SYSTEM_UI_FLAG_LAYOUT_STABLE andView.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION. For this to take effect, the window must be drawingthe system bar backgrounds with

attr.windowDrawsSystemBarBackgrounds and the navigation bar must not have been requested to be translucent with R.attr.windowTranslucentNavigation.Corresponds to Window.setNavigationBarColor(int).

An overridden method onCreateOptionsMenu in an Activity returns boolean value. What does this value mean?

You must return true for the menu to be displayed; if you return false it will not be shown.

You must return false for the menu to be displayed; if you return true it will not be shown.

You can return any value: the menu will be displayed anyway.

For example, suppose that in a XML file (res/menu/menu_main.xml as an example), where menu items are described, we have such item:

Only place this item in the app bar if there is room for it. If there is not room for all the items marked by this value, the items with the lowest orderInCategory values are displayed as actions, and the remaining items are displayed in theoverflow menu.

.<itemandroid:id="@+id/action_settings" android:orderInCategory="100"android:title="@string/menu_action_settings" app:showAsAction="never" />

.Attribute "app:showAsAction" shows when and how this item should appear as an action item in the app bar. What value "never" in this attribute means?

Only place this item in the app bar if there is room for it. If there is not room for all the items marked by this value, the items with the lowest orderInCategory values are displayed as actions, and the remaining items are displayed in theoverflow menu.

Also include the title text (defined by android:title) with the action item. You can include this value along with one of the others as a flag set, by separating them with a pipe.

Never place this item in the app bar. Instead, list the item in the app bar's overflow menu.

Always place this item in the app bar. Avoid using this unless it's critical that the item always appear in the action bar. Setting multiple items to always appear as action items can result in them overlapping with other UI in the app bar.