DialogFragment
open classDialogFragment: Fragment, DialogInterface.OnCancelListener, DialogInterface.OnDismissListener
| kotlin.Any | ||
| ↳ | android.app.Fragment | |
| ↳ | android.app.DialogFragment | |
A fragment that displays a dialog window, floating on top of its activity's window. This fragment contains a Dialog object, which it displays as appropriate based on the fragment's state. Control of the dialog (deciding when to show, hide, dismiss it) should be done through the API here, not with direct calls on the dialog.
Implementations should override this class and implement onCreateView(android.view.LayoutInflater,android.view.ViewGroup,android.os.Bundle) to supply the content of the dialog. Alternatively, they can override onCreateDialog(android.os.Bundle) to create an entirely custom dialog, such as an AlertDialog, with its own content.
Topics covered here:
Lifecycle
DialogFragment does various things to keep the fragment's lifecycle driving it, instead of the Dialog. Note that dialogs are generally autonomous entities -- they are their own window, receiving their own input events, and often deciding on their own when to disappear (by receiving a back key event or the user clicking on a button).
DialogFragment needs to ensure that what is happening with the Fragment and Dialog states remains consistent. To do this, it watches for dismiss events from the dialog and takes care of removing its own state when they happen. This means you should use show(android.app.FragmentManager,java.lang.String) or show(android.app.FragmentTransaction,java.lang.String) to add an instance of DialogFragment to your UI, as these keep track of how DialogFragment should remove itself when the dialog is dismissed.
Basic Dialog
The simplest use of DialogFragment is as a floating container for the fragment's view hierarchy. A simple implementation may look like this:
An example showDialog() method on the Activity could be:
This removes any currently shown dialog, creates a new DialogFragment with an argument, and shows it as a new state on the back stack. When the transaction is popped, the current DialogFragment and its Dialog will be destroyed, and the previous one (if any) re-shown. Note that in this case DialogFragment will take care of popping the transaction of the Dialog is dismissed separately from it.
Alert Dialog
Instead of (or in addition to) implementing onCreateView to generate the view hierarchy inside of a dialog, you may implement onCreateDialog(android.os.Bundle) to create your own custom Dialog object.
This is most useful for creating an AlertDialog, allowing you to display standard alerts to the user that are managed by a fragment. A simple example implementation of this is:
The activity creating this fragment may have the following methods to show the dialog and receive results from it:
Note that in this case the fragment is not placed on the back stack, it is just added as an indefinitely running fragment. Because dialogs normally are modal, this will still operate as a back stack, since the dialog will capture user input until it is dismissed. When it is dismissed, DialogFragment will take care of removing itself from its fragment manager.
Selecting Between Dialog or Embedding
A DialogFragment can still optionally be used as a normal fragment, if desired. This is useful if you have a fragment that in some cases should be shown as a dialog and others embedded in a larger UI. This behavior will normally be automatically selected for you based on how you are using the fragment, but can be customized with setShowsDialog(boolean).
For example, here is a simple dialog fragment:
An instance of this fragment can be created and shown as a dialog:
It can also be added as content in a view hierarchy:
Summary
| Constants | |
|---|---|
| static Int |
Style for |
| static Int |
Style for |
| static Int |
Style for |
| static Int |
Style for |
| Inherited constants | |
|---|---|
| Public constructors | |
|---|---|
| Public methods | |
|---|---|
| open Unit |
dismiss()Dismiss the fragment and its dialog. |
| open Unit |
Version of |
| open Unit |
dump(prefix: String!, fd: FileDescriptor!, writer: PrintWriter!, args: Array<String!>!)Print the Fragments's state into the given stream. |
| open Dialog! | |
| open Boolean |
Return the current value of |
| open Int |
getTheme() |
| open Boolean |
Return the current value of |
| open Unit |
onActivityCreated(savedInstanceState: Bundle?)Called when the fragment's activity has been created and this fragment's view hierarchy instantiated. |
| open Unit |
Called when a fragment is first attached to its context. |
| open Unit |
onCancel(dialog: DialogInterface!)This method will be invoked when the dialog is canceled. |
| open Unit |
Called to do initial creation of a fragment. |
| open Dialog! |
onCreateDialog(savedInstanceState: Bundle!)Override to build your own custom Dialog container. |
| open Unit |
Remove dialog. |
| open Unit |
onDetach()Called when the fragment is no longer attached to its activity. |
| open Unit |
onDismiss(dialog: DialogInterface!)This method will be invoked when the dialog is dismissed. |
| open LayoutInflater! |
onGetLayoutInflater(savedInstanceState: Bundle!) |
| open Unit |
onSaveInstanceState(outState: Bundle!)Called to ask the fragment to save its current dynamic state, so it can later be reconstructed in a new instance of its process is restarted. |
| open Unit |
onStart()Called when the Fragment is visible to the user. |
| open Unit |
onStop()Called when the Fragment is no longer started. |
| open Unit |
setCancelable(cancelable: Boolean)Control whether the shown Dialog is cancelable. |
| open Unit |
setShowsDialog(showsDialog: Boolean)Controls whether this fragment should be shown in a dialog. |
| open Unit |
Call to customize the basic appearance and behavior of the fragment's dialog. |
| open Unit |
show(manager: FragmentManager!, tag: String!)Display the dialog, adding the fragment to the given FragmentManager. |
| open Int |
show(transaction: FragmentTransaction!, tag: String!)Display the dialog, adding the fragment using an existing transaction and then committing the transaction. |
| Inherited functions | |
|---|---|
Constants
STYLE_NORMAL
static valSTYLE_NORMAL: Int
Deprecated: Deprecated in Java.
Style for setStyle(int,int): a basic, normal dialog.
Value: 0STYLE_NO_FRAME
static valSTYLE_NO_FRAME: Int
Deprecated: Deprecated in Java.
Style for setStyle(int,int): don't draw any frame at all; the view hierarchy returned by onCreateView is entirely responsible for drawing the dialog.
Value: 2STYLE_NO_INPUT
static valSTYLE_NO_INPUT: Int
Deprecated: Deprecated in Java.
Style for setStyle(int,int): like STYLE_NO_FRAME, but also disables all input to the dialog. The user can not touch it, and its window will not receive input focus.
Value: 3STYLE_NO_TITLE
static valSTYLE_NO_TITLE: Int
Deprecated: Deprecated in Java.
Style for setStyle(int,int): don't include a title area.
Value: 1Public constructors
Public methods
dismiss
open fundismiss(): Unit
Deprecated: Deprecated in Java.
Dismiss the fragment and its dialog. If the fragment was added to the back stack, all back stack state up to and including this entry will be popped. Otherwise, a new transaction will be committed to remove the fragment.
dismissAllowingStateLoss
open fundismissAllowingStateLoss(): Unit
Deprecated: Deprecated in Java.
Version of dismiss() that uses FragmentTransaction.commitAllowingStateLoss(). See linked documentation for further details.
dump
open fundump(
prefix: String!,
fd: FileDescriptor!,
writer: PrintWriter!,
args: Array<String!>!
): Unit
Deprecated: Deprecated in Java.
Print the Fragments's state into the given stream.
| Parameters | |
|---|---|
prefix |
String!: Text to print at the front of each line. |
fd |
FileDescriptor!: The raw file descriptor that the dump is being sent to. |
writer |
PrintWriter!: The PrintWriter to which you should dump your state. This will be closed for you after you return. |
args |
Array<String!>!: additional arguments to the dump request. |
getShowsDialog
open fungetShowsDialog(): Boolean
Deprecated: Deprecated in Java.
Return the current value of setShowsDialog(boolean).
isCancelable
open funisCancelable(): Boolean
Deprecated: Deprecated in Java.
Return the current value of setCancelable(boolean).
onActivityCreated
open funonActivityCreated(savedInstanceState: Bundle?): Unit
Deprecated: Deprecated in Java.
Called when the fragment's activity has been created and this fragment's view hierarchy instantiated. It can be used to do final initialization once these pieces are in place, such as retrieving views or restoring state. It is also useful for fragments that use setRetainInstance(boolean) to retain their instance, as this callback tells the fragment when it is fully associated with the new activity instance. This is called after onCreateView and before onViewStateRestored(android.os.Bundle).
If you override this method you must call through to the superclass implementation.
| Parameters | |
|---|---|
savedInstanceState |
Bundle?: If the fragment is being re-created from a previous saved state, this is the state. This value may be null. |
onAttach
open funonAttach(context: Context!): Unit
Deprecated: Deprecated in Java.
Called when a fragment is first attached to its context. onCreate(android.os.Bundle) will be called after this.
If you override this method you must call through to the superclass implementation.
onCancel
open funonCancel(dialog: DialogInterface!): Unit
Deprecated: Deprecated in Java.
This method will be invoked when the dialog is canceled.
| Parameters | |
|---|---|
dialog |
DialogInterface!: the dialog that was canceled will be passed into the method |
onCreate
open funonCreate(savedInstanceState: Bundle?): Unit
Deprecated: Deprecated in Java.
Called to do initial creation of a fragment. This is called after onAttach(android.app.Activity) and before onCreateView(android.view.LayoutInflater,android.view.ViewGroup,android.os.Bundle), but is not called if the fragment instance is retained across Activity re-creation (see setRetainInstance(boolean)).
Note that this can be called while the fragment's activity is still in the process of being created. As such, you can not rely on things like the activity's content view hierarchy being initialized at this point. If you want to do work once the activity itself is created, see onActivityCreated(android.os.Bundle).
If your app's targetSdkVersion is android.os.Build.VERSION_CODES#M or lower, child fragments being restored from the savedInstanceState are restored after onCreate returns. When targeting android.os.Build.VERSION_CODES#N or above and running on an N or newer platform version they are restored by Fragment.onCreate.
If you override this method you must call through to the superclass implementation.
| Parameters | |
|---|---|
savedInstanceState |
Bundle?: If the fragment is being re-created from a previous saved state, this is the state. This value may be null. |
onCreateDialog
open funonCreateDialog(savedInstanceState: Bundle!): Dialog!
Deprecated: Deprecated in Java.
Override to build your own custom Dialog container. This is typically used to show an AlertDialog instead of a generic Dialog; when doing so, onCreateView(android.view.LayoutInflater,android.view.ViewGroup,android.os.Bundle) does not need to be implemented since the AlertDialog takes care of its own content.
This method will be called after onCreate(android.os.Bundle) and before onCreateView(android.view.LayoutInflater,android.view.ViewGroup,android.os.Bundle). The default implementation simply instantiates and returns a Dialog class.
Note: DialogFragment own the Dialog.setOnCancelListener and Dialog.setOnDismissListener callbacks. You must not set them yourself. To find out about these events, override onCancel(android.content.DialogInterface) and onDismiss(android.content.DialogInterface).
| Parameters | |
|---|---|
savedInstanceState |
Bundle!: The last saved instance state of the Fragment, or null if this is a freshly created Fragment. |
| Return | |
|---|---|
Dialog! |
Return a new Dialog instance to be displayed by the Fragment. |
onDestroyView
open funonDestroyView(): Unit
Deprecated: Deprecated in Java.
Remove dialog.
onDetach
open funonDetach(): Unit
Deprecated: Deprecated in Java.
Called when the fragment is no longer attached to its activity. This is called after onDestroy(), except in the cases where the fragment instance is retained across Activity re-creation (see setRetainInstance(boolean)), in which case it is called after onStop().
If you override this method you must call through to the superclass implementation.
onDismiss
open funonDismiss(dialog: DialogInterface!): Unit
Deprecated: Deprecated in Java.
This method will be invoked when the dialog is dismissed.
| Parameters | |
|---|---|
dialog |
DialogInterface!: the dialog that was dismissed will be passed into the method |
onGetLayoutInflater
open funonGetLayoutInflater(savedInstanceState: Bundle!): LayoutInflater!
Deprecated: Deprecated in Java.
| Return | |
|---|---|
LayoutInflater! |
The LayoutInflater used to inflate Views of this Fragment. |
onSaveInstanceState
open funonSaveInstanceState(outState: Bundle!): Unit
Deprecated: Deprecated in Java.
Called to ask the fragment to save its current dynamic state, so it can later be reconstructed in a new instance of its process is restarted. If a new instance of the fragment later needs to be created, the data you place in the Bundle here will be available in the Bundle given to onCreate(android.os.Bundle), onCreateView(android.view.LayoutInflater,android.view.ViewGroup,android.os.Bundle), and onActivityCreated(android.os.Bundle).
This corresponds to Activity.onSaveInstanceState(Bundle) and most of the discussion there applies here as well. Note however: this method may be called at any time before onDestroy(). There are many situations where a fragment may be mostly torn down (such as when placed on the back stack with no UI showing), but its state will not be saved until its owning activity actually needs to save its state.
| Parameters | |
|---|---|
outState |
Bundle!: Bundle in which to place your saved state. |
onStart
open funonStart(): Unit
Deprecated: Deprecated in Java.
Called when the Fragment is visible to the user. This is generally tied to Activity.onStart of the containing Activity's lifecycle.
If you override this method you must call through to the superclass implementation.
onStop
open funonStop(): Unit
Deprecated: Deprecated in Java.
Called when the Fragment is no longer started. This is generally tied to Activity.onStop of the containing Activity's lifecycle.
If you override this method you must call through to the superclass implementation.
setCancelable
open funsetCancelable(cancelable: Boolean): Unit
Deprecated: Deprecated in Java.
Control whether the shown Dialog is cancelable. Use this instead of directly calling Dialog.setCancelable(boolean), because DialogFragment needs to change its behavior based on this.
| Parameters | |
|---|---|
cancelable |
Boolean: If true, the dialog is cancelable. The default is true. |
setShowsDialog
open funsetShowsDialog(showsDialog: Boolean): Unit
Deprecated: Deprecated in Java.
Controls whether this fragment should be shown in a dialog. If not set, no Dialog will be created in onActivityCreated(android.os.Bundle), and the fragment's view hierarchy will thus not be added to it. This allows you to instead use it as a normal fragment (embedded inside of its activity).
This is normally set for you based on whether the fragment is associated with a container view ID passed to FragmentTransaction.add(int, Fragment). If the fragment was added with a container, setShowsDialog will be initialized to false; otherwise, it will be true.
| Parameters | |
|---|---|
showsDialog |
Boolean: If true, the fragment will be displayed in a Dialog. If false, no Dialog will be created and the fragment's view hierarchly left undisturbed. |
setStyle
open funsetStyle(
style: Int,
theme: Int
): Unit
Deprecated: Deprecated in Java.
Call to customize the basic appearance and behavior of the fragment's dialog. This can be used for some common dialog behaviors, taking care of selecting flags, theme, and other options for you. The same effect can be achieve by manually setting Dialog and Window attributes yourself. Calling this after the fragment's Dialog is created will have no effect.
| Parameters | |
|---|---|
style |
Int: Selects a standard style: may be STYLE_NORMAL, STYLE_NO_TITLE, STYLE_NO_FRAME, or STYLE_NO_INPUT. |
theme |
Int: Optional custom theme. If 0, an appropriate theme (based on the style) will be selected for you. |
show
open funshow(
manager: FragmentManager!,
tag: String!
): Unit
Deprecated: Deprecated in Java.
Display the dialog, adding the fragment to the given FragmentManager. This is a convenience for explicitly creating a transaction, adding the fragment to it with the given tag, and committing it. This does not add the transaction to the back stack. When the fragment is dismissed, a new transaction will be executed to remove it from the activity.
| Parameters | |
|---|---|
manager |
FragmentManager!: The FragmentManager this fragment will be added to. |
tag |
String!: The tag for this fragment, as per FragmentTransaction.add. |
show
open funshow(
transaction: FragmentTransaction!,
tag: String!
): Int
Deprecated: Deprecated in Java.
Display the dialog, adding the fragment using an existing transaction and then committing the transaction.
| Parameters | |
|---|---|
transaction |
FragmentTransaction!: An existing transaction in which to add the fragment. |
tag |
String!: The tag for this fragment, as per FragmentTransaction.add. |
| Return | |
|---|---|
Int |
Returns the identifier of the committed transaction, as per FragmentTransaction.commit(). |