added in version 22.1.0
belongs to Maven artifact com.android.support:support-compat:28.0.0-alpha1

TaskStackBuilder

public final class TaskStackBuilder
extends Object implements Iterable<Intent>

java.lang.Object
   ↳ android.support.v4.app.TaskStackBuilder


Utility class for constructing synthetic back stacks for cross-task navigation on Android 3.0 and newer.

In API level 11 (Android 3.0/Honeycomb) the recommended conventions for app navigation using the back key changed. The back key's behavior is local to the current task and does not capture navigation across different tasks. Navigating across tasks and easily reaching the previous task is accomplished through the "recents" UI, accessible through the software-provided Recents key on the navigation or system bar. On devices with the older hardware button configuration the recents UI can be accessed with a long press on the Home key.

When crossing from one task stack to another post-Android 3.0, the application should synthesize a back stack/history for the new task so that the user may navigate out of the new task and back to the Launcher by repeated presses of the back key. Back key presses should not navigate across task stacks.

TaskStackBuilder provides a backward-compatible way to obey the correct conventions around cross-task navigation on the device's version of the platform. On devices running Android 3.0 or newer, calls to the startActivities() method or sending the PendingIntent generated by getPendingIntent(int, int) will construct the synthetic back stack as prescribed. On devices running older versions of the platform, these same calls will invoke the topmost activity in the supplied stack, ignoring the rest of the synthetic stack and allowing the back key to navigate back to the previous task.

About Navigation

For more detailed information about tasks, the back stack, and navigation design guidelines, please read Tasks and Back Stack from the developer guide and Navigation from the design guide.

Summary

Nested classes

interface TaskStackBuilder.SupportParentable

 

Public methods

TaskStackBuilder addNextIntent(Intent nextIntent)

Add a new Intent to the task stack.

TaskStackBuilder addNextIntentWithParentStack(Intent nextIntent)

Add a new Intent with the resolved chain of parents for the target activity to the task stack.

TaskStackBuilder addParentStack(ComponentName sourceActivityName)

Add the activity parent chain as specified by manifest <meta-data> elements to the task stack builder.

TaskStackBuilder addParentStack(Activity sourceActivity)

Add the activity parent chain as specified by manifest <meta-data> elements to the task stack builder.

TaskStackBuilder addParentStack(Class<?> sourceActivityClass)

Add the activity parent chain as specified by manifest <meta-data> elements to the task stack builder.

static TaskStackBuilder create(Context context)

Return a new TaskStackBuilder for launching a fresh task stack consisting of a series of activities.

Intent editIntentAt(int index)

Return the intent at the specified index for modification.

static TaskStackBuilder from(Context context)

This method was deprecated in API level 22.1.0. use create(Context) instead

Intent getIntent(int index)

This method was deprecated in API level 22.1.0. Renamed to editIntentAt to better reflect intended usage

int getIntentCount()
Intent[] getIntents()

Return an array containing the intents added to this builder.

PendingIntent getPendingIntent(int requestCode, int flags)

Obtain a PendingIntent for launching the task constructed by this builder so far.

PendingIntent getPendingIntent(int requestCode, int flags, Bundle options)

Obtain a PendingIntent for launching the task constructed by this builder so far.

Iterator<Intent> iterator()

This method was deprecated in API level 22.1.0. Use editIntentAt instead

void startActivities()

Start the task stack constructed by this builder.

void startActivities(Bundle options)

Start the task stack constructed by this builder.

Inherited methods

From class java.lang.Object
From interface java.lang.Iterable

Public methods

addNextIntent

added in version 22.1.0
TaskStackBuilder addNextIntent (Intent nextIntent)

Add a new Intent to the task stack. The most recently added Intent will invoke the Activity at the top of the final task stack.

Parameters
nextIntent Intent: Intent for the next Activity in the synthesized task stack

Returns
TaskStackBuilder This TaskStackBuilder for method chaining

addNextIntentWithParentStack

added in version 22.1.0
TaskStackBuilder addNextIntentWithParentStack (Intent nextIntent)

Add a new Intent with the resolved chain of parents for the target activity to the task stack.

This is equivalent to calling addParentStack with the resolved ComponentName of nextIntent (if it can be resolved), followed by addNextIntent with nextIntent.

Parameters
nextIntent Intent: Intent for the topmost Activity in the synthesized task stack. Its chain of parents as specified in the manifest will be added.

Returns
TaskStackBuilder This TaskStackBuilder for method chaining.

addParentStack

added in version 22.1.0
TaskStackBuilder addParentStack (ComponentName sourceActivityName)

Add the activity parent chain as specified by manifest <meta-data> elements to the task stack builder.

Parameters
sourceActivityName ComponentName: Must specify an Activity component. All parents of this activity will be added

Returns
TaskStackBuilder This TaskStackBuilder for method chaining

addParentStack

added in version 22.1.0
TaskStackBuilder addParentStack (Activity sourceActivity)

Add the activity parent chain as specified by manifest <meta-data> elements to the task stack builder.

Parameters
sourceActivity Activity: All parents of this activity will be added

Returns
TaskStackBuilder This TaskStackBuilder for method chaining

addParentStack

added in version 22.1.0
TaskStackBuilder addParentStack (Class<?> sourceActivityClass)

Add the activity parent chain as specified by manifest <meta-data> elements to the task stack builder.

Parameters
sourceActivityClass Class: All parents of this activity will be added

Returns
TaskStackBuilder This TaskStackBuilder for method chaining

create

added in version 22.1.0
TaskStackBuilder create (Context context)

Return a new TaskStackBuilder for launching a fresh task stack consisting of a series of activities.

Parameters
context Context: The context that will launch the new task stack or generate a PendingIntent

Returns
TaskStackBuilder A new TaskStackBuilder

editIntentAt

added in version 22.1.0
Intent editIntentAt (int index)

Return the intent at the specified index for modification. Useful if you need to modify the flags or extras of an intent that was previously added, for example with addParentStack(Activity).

Parameters
index int: Index from 0-getIntentCount()

Returns
Intent the intent at position index

from

added in version 22.1.0
TaskStackBuilder from (Context context)

This method was deprecated in API level 22.1.0.
use create(Context) instead

Return a new TaskStackBuilder for launching a fresh task stack consisting of a series of activities.

Parameters
context Context: The context that will launch the new task stack or generate a PendingIntent

Returns
TaskStackBuilder A new TaskStackBuilder

getIntent

added in version 22.1.0
Intent getIntent (int index)

This method was deprecated in API level 22.1.0.
Renamed to editIntentAt to better reflect intended usage

Get the intent at the specified index. Useful if you need to modify the flags or extras of an intent that was previously added, for example with addParentStack(Activity).

Parameters
index int: Index from 0-getIntentCount()

Returns
Intent the intent at position index

getIntentCount

added in version 22.1.0
int getIntentCount ()

Returns
int the number of intents added so far.

getIntents

added in version 22.1.0
Intent[] getIntents ()

Return an array containing the intents added to this builder. The intent at the root of the task stack will appear as the first item in the array and the intent at the top of the stack will appear as the last item.

Returns
Intent[] An array containing the intents added to this builder.

getPendingIntent

added in version 22.1.0
PendingIntent getPendingIntent (int requestCode, 
                int flags)

Obtain a PendingIntent for launching the task constructed by this builder so far.

Parameters
requestCode int: Private request code for the sender

flags int: May be FLAG_ONE_SHOT, FLAG_NO_CREATE, FLAG_CANCEL_CURRENT, FLAG_UPDATE_CURRENT, or any of the flags supported by fillIn(Intent, int) to control which unspecified parts of the intent that can be supplied when the actual send happens.

Returns
PendingIntent The obtained PendingIntent. May return null only if FLAG_NO_CREATE has been supplied.

getPendingIntent

added in version 22.1.0
PendingIntent getPendingIntent (int requestCode, 
                int flags, 
                Bundle options)

Obtain a PendingIntent for launching the task constructed by this builder so far.

Parameters
requestCode int: Private request code for the sender

flags int: May be FLAG_ONE_SHOT, FLAG_NO_CREATE, FLAG_CANCEL_CURRENT, FLAG_UPDATE_CURRENT, or any of the flags supported by fillIn(Intent, int) to control which unspecified parts of the intent that can be supplied when the actual send happens.

options Bundle: Additional options for how the Activity should be started. See startActivity(Intent, Bundle)

Returns
PendingIntent The obtained PendingIntent. May return null only if FLAG_NO_CREATE has been supplied.

iterator

added in version 22.1.0
Iterator<Intent> iterator ()

This method was deprecated in API level 22.1.0.
Use editIntentAt instead

Returns
Iterator<Intent>

startActivities

added in version 22.1.0
void startActivities ()

Start the task stack constructed by this builder. The Context used to obtain this builder must be an Activity.

On devices that do not support API level 11 or higher the topmost activity will be started as a new task. On devices that do support API level 11 or higher the new task stack will be created in its entirety.

startActivities

added in version 22.1.0
void startActivities (Bundle options)

Start the task stack constructed by this builder. The Context used to obtain this builder must be an Activity.

On devices that do not support API level 11 or higher the topmost activity will be started as a new task. On devices that do support API level 11 or higher the new task stack will be created in its entirety.

Parameters
options Bundle: Additional options for how the Activity should be started. See startActivity(Intent, Bundle)