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Added in API level 11

DialogFragment

public class DialogFragment
extends Fragment implements DialogInterface.OnCancelListener, DialogInterface.OnDismissListener

java.lang.Object
   ↳ android.app.Fragment
     ↳ android.app.DialogFragment
Known Direct Subclasses
Known Indirect Subclasses


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(LayoutInflater, ViewGroup, Bundle) to supply the content of the dialog. Alternatively, they can override onCreateDialog(Bundle) to create an entirely custom dialog, such as an AlertDialog, with its own content.

Topics covered here:

  1. Lifecycle
  2. Basic Dialog
  3. Alert Dialog
  4. Selecting Between Dialog or Embedding

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(FragmentManager, String) or show(FragmentTransaction, 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:

public static class MyDialogFragment extends DialogFragment {
    int mNum;

    /**
     * Create a new instance of MyDialogFragment, providing "num"
     * as an argument.
     */
    static MyDialogFragment newInstance(int num) {
        MyDialogFragment f = new MyDialogFragment();

        // Supply num input as an argument.
        Bundle args = new Bundle();
        args.putInt("num", num);
        f.setArguments(args);

        return f;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mNum = getArguments().getInt("num");

        // Pick a style based on the num.
        int style = DialogFragment.STYLE_NORMAL, theme = 0;
        switch ((mNum-1)%6) {
            case 1: style = DialogFragment.STYLE_NO_TITLE; break;
            case 2: style = DialogFragment.STYLE_NO_FRAME; break;
            case 3: style = DialogFragment.STYLE_NO_INPUT; break;
            case 4: style = DialogFragment.STYLE_NORMAL; break;
            case 5: style = DialogFragment.STYLE_NORMAL; break;
            case 6: style = DialogFragment.STYLE_NO_TITLE; break;
            case 7: style = DialogFragment.STYLE_NO_FRAME; break;
            case 8: style = DialogFragment.STYLE_NORMAL; break;
        }
        switch ((mNum-1)%6) {
            case 4: theme = android.R.style.Theme_Holo; break;
            case 5: theme = android.R.style.Theme_Holo_Light_Dialog; break;
            case 6: theme = android.R.style.Theme_Holo_Light; break;
            case 7: theme = android.R.style.Theme_Holo_Light_Panel; break;
            case 8: theme = android.R.style.Theme_Holo_Light; break;
        }
        setStyle(style, theme);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.fragment_dialog, container, false);
        View tv = v.findViewById(R.id.text);
        ((TextView)tv).setText("Dialog #" + mNum + ": using style "
                + getNameForNum(mNum));

        // Watch for button clicks.
        Button button = (Button)v.findViewById(R.id.show);
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                // When button is clicked, call up to owning activity.
                ((FragmentDialog)getActivity()).showDialog();
            }
        });

        return v;
    }
}

An example showDialog() method on the Activity could be:

void showDialog() {
    mStackLevel++;

    // DialogFragment.show() will take care of adding the fragment
    // in a transaction.  We also want to remove any currently showing
    // dialog, so make our own transaction and take care of that here.
    FragmentTransaction ft = getFragmentManager().beginTransaction();
    Fragment prev = getFragmentManager().findFragmentByTag("dialog");
    if (prev != null) {
        ft.remove(prev);
    }
    ft.addToBackStack(null);

    // Create and show the dialog.
    DialogFragment newFragment = MyDialogFragment.newInstance(mStackLevel);
    newFragment.show(ft, "dialog");
}

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(LayoutInflater, ViewGroup, Bundle) to generate the view hierarchy inside of a dialog, you may implement onCreateDialog(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:

public static class MyAlertDialogFragment extends DialogFragment {

    public static MyAlertDialogFragment newInstance(int title) {
        MyAlertDialogFragment frag = new MyAlertDialogFragment();
        Bundle args = new Bundle();
        args.putInt("title", title);
        frag.setArguments(args);
        return frag;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        int title = getArguments().getInt("title");

        return new AlertDialog.Builder(getActivity())
                .setIcon(R.drawable.alert_dialog_icon)
                .setTitle(title)
                .setPositiveButton(R.string.alert_dialog_ok,
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int whichButton) {
                            ((FragmentAlertDialog)getActivity()).doPositiveClick();
                        }
                    }
                )
                .setNegativeButton(R.string.alert_dialog_cancel,
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int whichButton) {
                            ((FragmentAlertDialog)getActivity()).doNegativeClick();
                        }
                    }
                )
                .create();
    }
}

The activity creating this fragment may have the following methods to show the dialog and receive results from it:

void showDialog() {
    DialogFragment newFragment = MyAlertDialogFragment.newInstance(
            R.string.alert_dialog_two_buttons_title);
    newFragment.show(getFragmentManager(), "dialog");
}

public void doPositiveClick() {
    // Do stuff here.
    Log.i("FragmentAlertDialog", "Positive click!");
}

public void doNegativeClick() {
    // Do stuff here.
    Log.i("FragmentAlertDialog", "Negative click!");
}

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:

public static class MyDialogFragment extends DialogFragment {
    static MyDialogFragment newInstance() {
        return new MyDialogFragment();
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.hello_world, container, false);
        View tv = v.findViewById(R.id.text);
        ((TextView)tv).setText("This is an instance of MyDialogFragment");
        return v;
    }
}

An instance of this fragment can be created and shown as a dialog:

void showDialog() {
    // Create the fragment and show it as a dialog.
    DialogFragment newFragment = MyDialogFragment.newInstance();
    newFragment.show(getFragmentManager(), "dialog");
}

It can also be added as content in a view hierarchy:

FragmentTransaction ft = getFragmentManager().beginTransaction();
DialogFragment newFragment = MyDialogFragment.newInstance();
ft.add(R.id.embedded, newFragment);
ft.commit();

Summary

Inherited XML attributes

From class android.app.Fragment

Constants

int STYLE_NORMAL

Style for setStyle(int, int): a basic, normal dialog.

int STYLE_NO_FRAME

Style for setStyle(int, int): don't draw any frame at all; the view hierarchy returned by onCreateView(LayoutInflater, ViewGroup, Bundle) is entirely responsible for drawing the dialog.

int STYLE_NO_INPUT

Style for setStyle(int, int): like STYLE_NO_FRAME, but also disables all input to the dialog.

int STYLE_NO_TITLE

Style for setStyle(int, int): don't include a title area.

Inherited constants

From interface android.content.ComponentCallbacks2

Public constructors

DialogFragment()

Public methods

void dismiss()

Dismiss the fragment and its dialog.

void dismissAllowingStateLoss()

Version of dismiss() that uses FragmentTransaction.commitAllowingStateLoss().

void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args)

Print the Fragments's state into the given stream.

Dialog getDialog()
boolean getShowsDialog()

Return the current value of setShowsDialog(boolean).

int getTheme()
boolean isCancelable()

Return the current value of setCancelable(boolean).

void onActivityCreated(Bundle savedInstanceState)

Called when the fragment's activity has been created and this fragment's view hierarchy instantiated.

void onAttach(Context context)

Called when a fragment is first attached to its context.

void onCancel(DialogInterface dialog)

This method will be invoked when the dialog is canceled.

void onCreate(Bundle savedInstanceState)

Called to do initial creation of a fragment.

Dialog onCreateDialog(Bundle savedInstanceState)

Override to build your own custom Dialog container.

void onDestroyView()

Remove dialog.

void onDetach()

Called when the fragment is no longer attached to its activity.

void onDismiss(DialogInterface dialog)

This method will be invoked when the dialog is dismissed.

void onSaveInstanceState(Bundle outState)

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.

void onStart()

Called when the Fragment is visible to the user.

void onStop()

Called when the Fragment is no longer started.

void setCancelable(boolean cancelable)

Control whether the shown Dialog is cancelable.

void setShowsDialog(boolean showsDialog)

Controls whether this fragment should be shown in a dialog.

void setStyle(int style, int theme)

Call to customize the basic appearance and behavior of the fragment's dialog.

void show(FragmentManager manager, String tag)

Display the dialog, adding the fragment to the given FragmentManager.

int show(FragmentTransaction transaction, String tag)

Display the dialog, adding the fragment using an existing transaction and then committing the transaction.

Inherited methods

From class android.app.Fragment
From class java.lang.Object
From interface android.content.ComponentCallbacks2
From interface android.view.View.OnCreateContextMenuListener
From interface android.content.DialogInterface.OnCancelListener
From interface android.content.DialogInterface.OnDismissListener
From interface android.content.ComponentCallbacks

Constants

STYLE_NORMAL

Added in API level 11
int STYLE_NORMAL

Style for setStyle(int, int): a basic, normal dialog.

Constant Value: 0 (0x00000000)

STYLE_NO_FRAME

Added in API level 11
int STYLE_NO_FRAME

Style for setStyle(int, int): don't draw any frame at all; the view hierarchy returned by onCreateView(LayoutInflater, ViewGroup, Bundle) is entirely responsible for drawing the dialog.

Constant Value: 2 (0x00000002)

STYLE_NO_INPUT

Added in API level 11
int STYLE_NO_INPUT

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.

Constant Value: 3 (0x00000003)

STYLE_NO_TITLE

Added in API level 11
int STYLE_NO_TITLE

Style for setStyle(int, int): don't include a title area.

Constant Value: 1 (0x00000001)

Public constructors

DialogFragment

Added in API level 11
DialogFragment ()

Public methods

dismiss

Added in API level 11
void dismiss ()

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

Added in API level 12
void dismissAllowingStateLoss ()

Version of dismiss() that uses FragmentTransaction.commitAllowingStateLoss(). See linked documentation for further details.

dump

Added in API level 11
void dump (String prefix, 
                FileDescriptor fd, 
                PrintWriter writer, 
                String[] args)

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 String: additional arguments to the dump request.

getDialog

Added in API level 11
Dialog getDialog ()

Returns
Dialog

getShowsDialog

Added in API level 11
boolean getShowsDialog ()

Return the current value of setShowsDialog(boolean).

Returns
boolean

getTheme

Added in API level 11
int getTheme ()

Returns
int

isCancelable

Added in API level 11
boolean isCancelable ()

Return the current value of setCancelable(boolean).

Returns
boolean

onActivityCreated

Added in API level 11
void onActivityCreated (Bundle savedInstanceState)

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(LayoutInflater, ViewGroup, Bundle) and before onViewStateRestored(Bundle).

Parameters
savedInstanceState Bundle: If the fragment is being re-created from a previous saved state, this is the state.

onAttach

Added in API level 23
void onAttach (Context context)

Called when a fragment is first attached to its context. onCreate(Bundle) will be called after this.

Parameters
context Context

onCancel

Added in API level 11
void onCancel (DialogInterface dialog)

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

Added in API level 11
void onCreate (Bundle savedInstanceState)

Called to do initial creation of a fragment. This is called after onAttach(Activity) and before onCreateView(LayoutInflater, ViewGroup, 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(Bundle).

If your app's targetSdkVersion is 23 or lower, child fragments being restored from the savedInstanceState are restored after onCreate returns. When targeting N or above and running on an N or newer platform version they are restored by Fragment.onCreate.

Parameters
savedInstanceState Bundle: If the fragment is being re-created from a previous saved state, this is the state.

onCreateDialog

Added in API level 11
Dialog onCreateDialog (Bundle savedInstanceState)

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(LayoutInflater, ViewGroup, Bundle) does not need to be implemented since the AlertDialog takes care of its own content.

This method will be called after onCreate(Bundle) and before onCreateView(LayoutInflater, ViewGroup, 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(DialogInterface) and onDismiss(DialogInterface).

Parameters
savedInstanceState Bundle: The last saved instance state of the Fragment, or null if this is a freshly created Fragment.
Returns
Dialog Return a new Dialog instance to be displayed by the Fragment.

onDestroyView

Added in API level 11
void onDestroyView ()

Remove dialog.

onDetach

Added in API level 11
void onDetach ()

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().

onDismiss

Added in API level 11
void onDismiss (DialogInterface dialog)

This method will be invoked when the dialog is dismissed.

Parameters
dialog DialogInterface: The dialog that was dismissed will be passed into the method.

onSaveInstanceState

Added in API level 11
void onSaveInstanceState (Bundle outState)

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(Bundle), onCreateView(LayoutInflater, ViewGroup, Bundle), and onActivityCreated(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

Added in API level 11
void onStart ()

Called when the Fragment is visible to the user. This is generally tied to Activity.onStart of the containing Activity's lifecycle.

onStop

Added in API level 11
void onStop ()

Called when the Fragment is no longer started. This is generally tied to Activity.onStop of the containing Activity's lifecycle.

setCancelable

Added in API level 11
void setCancelable (boolean cancelable)

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

Added in API level 11
void setShowsDialog (boolean showsDialog)

Controls whether this fragment should be shown in a dialog. If not set, no Dialog will be created in onActivityCreated(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

Added in API level 11
void setStyle (int style, 
                int theme)

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

Added in API level 11
void show (FragmentManager manager, 
                String tag)

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

Added in API level 11
int show (FragmentTransaction transaction, 
                String tag)

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.
Returns
int Returns the identifier of the committed transaction, as per FragmentTransaction.commit().

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