1package android.app;
2
3import android.util.Pair;
4import android.view.View;
5
6/**
7 * API for performing a set of Fragment operations.
8 *
9 * <div class="special reference">
10 * <h3>Developer Guides</h3>
11 * <p>For more information about using fragments, read the
12 * <a href="{@docRoot}guide/topics/fundamentals/fragments.html">Fragments</a> developer guide.</p>
13 * </div>
14 */
15public abstract class FragmentTransaction {
16    /**
17     * Calls {@link #add(int, Fragment, String)} with a 0 containerViewId.
18     */
19    public abstract FragmentTransaction add(Fragment fragment, String tag);
20
21    /**
22     * Calls {@link #add(int, Fragment, String)} with a null tag.
23     */
24    public abstract FragmentTransaction add(int containerViewId, Fragment fragment);
25
26    /**
27     * Add a fragment to the activity state.  This fragment may optionally
28     * also have its view (if {@link Fragment#onCreateView Fragment.onCreateView}
29     * returns non-null) into a container view of the activity.
30     *
31     * @param containerViewId Optional identifier of the container this fragment is
32     * to be placed in.  If 0, it will not be placed in a container.
33     * @param fragment The fragment to be added.  This fragment must not already
34     * be added to the activity.
35     * @param tag Optional tag name for the fragment, to later retrieve the
36     * fragment with {@link FragmentManager#findFragmentByTag(String)
37     * FragmentManager.findFragmentByTag(String)}.
38     *
39     * @return Returns the same FragmentTransaction instance.
40     */
41    public abstract FragmentTransaction add(int containerViewId, Fragment fragment, String tag);
42
43    /**
44     * Calls {@link #replace(int, Fragment, String)} with a null tag.
45     */
46    public abstract FragmentTransaction replace(int containerViewId, Fragment fragment);
47
48    /**
49     * Replace an existing fragment that was added to a container.  This is
50     * essentially the same as calling {@link #remove(Fragment)} for all
51     * currently added fragments that were added with the same containerViewId
52     * and then {@link #add(int, Fragment, String)} with the same arguments
53     * given here.
54     *
55     * @param containerViewId Identifier of the container whose fragment(s) are
56     * to be replaced.
57     * @param fragment The new fragment to place in the container.
58     * @param tag Optional tag name for the fragment, to later retrieve the
59     * fragment with {@link FragmentManager#findFragmentByTag(String)
60     * FragmentManager.findFragmentByTag(String)}.
61     *
62     * @return Returns the same FragmentTransaction instance.
63     */
64    public abstract FragmentTransaction replace(int containerViewId, Fragment fragment, String tag);
65
66    /**
67     * Remove an existing fragment.  If it was added to a container, its view
68     * is also removed from that container.
69     *
70     * @param fragment The fragment to be removed.
71     *
72     * @return Returns the same FragmentTransaction instance.
73     */
74    public abstract FragmentTransaction remove(Fragment fragment);
75
76    /**
77     * Hides an existing fragment.  This is only relevant for fragments whose
78     * views have been added to a container, as this will cause the view to
79     * be hidden.
80     *
81     * @param fragment The fragment to be hidden.
82     *
83     * @return Returns the same FragmentTransaction instance.
84     */
85    public abstract FragmentTransaction hide(Fragment fragment);
86
87    /**
88     * Shows a previously hidden fragment.  This is only relevant for fragments whose
89     * views have been added to a container, as this will cause the view to
90     * be shown.
91     *
92     * @param fragment The fragment to be shown.
93     *
94     * @return Returns the same FragmentTransaction instance.
95     */
96    public abstract FragmentTransaction show(Fragment fragment);
97
98    /**
99     * Detach the given fragment from the UI.  This is the same state as
100     * when it is put on the back stack: the fragment is removed from
101     * the UI, however its state is still being actively managed by the
102     * fragment manager.  When going into this state its view hierarchy
103     * is destroyed.
104     *
105     * @param fragment The fragment to be detached.
106     *
107     * @return Returns the same FragmentTransaction instance.
108     */
109    public abstract FragmentTransaction detach(Fragment fragment);
110
111    /**
112     * Re-attach a fragment after it had previously been detached from
113     * the UI with {@link #detach(Fragment)}.  This
114     * causes its view hierarchy to be re-created, attached to the UI,
115     * and displayed.
116     *
117     * @param fragment The fragment to be attached.
118     *
119     * @return Returns the same FragmentTransaction instance.
120     */
121    public abstract FragmentTransaction attach(Fragment fragment);
122
123    /**
124     * @return <code>true</code> if this transaction contains no operations,
125     * <code>false</code> otherwise.
126     */
127    public abstract boolean isEmpty();
128
129    /**
130     * Bit mask that is set for all enter transitions.
131     */
132    public static final int TRANSIT_ENTER_MASK = 0x1000;
133
134    /**
135     * Bit mask that is set for all exit transitions.
136     */
137    public static final int TRANSIT_EXIT_MASK = 0x2000;
138
139    /** Not set up for a transition. */
140    public static final int TRANSIT_UNSET = -1;
141    /** No animation for transition. */
142    public static final int TRANSIT_NONE = 0;
143    /** Fragment is being added onto the stack */
144    public static final int TRANSIT_FRAGMENT_OPEN = 1 | TRANSIT_ENTER_MASK;
145    /** Fragment is being removed from the stack */
146    public static final int TRANSIT_FRAGMENT_CLOSE = 2 | TRANSIT_EXIT_MASK;
147    /** Fragment should simply fade in or out; that is, no strong navigation associated
148     * with it except that it is appearing or disappearing for some reason. */
149    public static final int TRANSIT_FRAGMENT_FADE = 3 | TRANSIT_ENTER_MASK;
150
151    /**
152     * Set specific animation resources to run for the fragments that are
153     * entering and exiting in this transaction. These animations will not be
154     * played when popping the back stack.
155     */
156    public abstract FragmentTransaction setCustomAnimations(int enter, int exit);
157
158    /**
159     * Set specific animation resources to run for the fragments that are
160     * entering and exiting in this transaction. The <code>popEnter</code>
161     * and <code>popExit</code> animations will be played for enter/exit
162     * operations specifically when popping the back stack.
163     */
164    public abstract FragmentTransaction setCustomAnimations(int enter, int exit,
165            int popEnter, int popExit);
166
167    /**
168     * Select a standard transition animation for this transaction.  May be
169     * one of {@link #TRANSIT_NONE}, {@link #TRANSIT_FRAGMENT_OPEN},
170     * or {@link #TRANSIT_FRAGMENT_CLOSE}
171     */
172    public abstract FragmentTransaction setTransition(int transit);
173
174    /**
175     * TODO: remove from API
176     * @hide
177     */
178    public FragmentTransaction setCustomTransition(int sceneRootId, int transitionId) {
179        return this;
180    }
181
182    /**
183     * Used with to map a View from a removed or hidden Fragment to a View from a shown
184     * or added Fragment.
185     * @param sharedElement A View in a disappearing Fragment to match with a View in an
186     *                      appearing Fragment.
187     * @param name The transitionName for a View in an appearing Fragment to match to the shared
188     *             element.
189     */
190    public abstract FragmentTransaction addSharedElement(View sharedElement, String name);
191
192    /**
193     * TODO: remove from API
194     * @hide
195     */
196    public abstract FragmentTransaction setSharedElement(View sharedElement, String name);
197
198    /**
199     * TODO: remove from API
200     * @hide
201     */
202    public abstract FragmentTransaction setSharedElements(Pair<View, String>... sharedElements);
203
204    /**
205     * Set a custom style resource that will be used for resolving transit
206     * animations.
207     */
208    public abstract FragmentTransaction setTransitionStyle(int styleRes);
209
210    /**
211     * Add this transaction to the back stack.  This means that the transaction
212     * will be remembered after it is committed, and will reverse its operation
213     * when later popped off the stack.
214     *
215     * @param name An optional name for this back stack state, or null.
216     */
217    public abstract FragmentTransaction addToBackStack(String name);
218
219    /**
220     * Returns true if this FragmentTransaction is allowed to be added to the back
221     * stack. If this method would return false, {@link #addToBackStack(String)}
222     * will throw {@link IllegalStateException}.
223     *
224     * @return True if {@link #addToBackStack(String)} is permitted on this transaction.
225     */
226    public abstract boolean isAddToBackStackAllowed();
227
228    /**
229     * Disallow calls to {@link #addToBackStack(String)}. Any future calls to
230     * addToBackStack will throw {@link IllegalStateException}. If addToBackStack
231     * has already been called, this method will throw IllegalStateException.
232     */
233    public abstract FragmentTransaction disallowAddToBackStack();
234
235    /**
236     * Set the full title to show as a bread crumb when this transaction
237     * is on the back stack, as used by {@link FragmentBreadCrumbs}.
238     *
239     * @param res A string resource containing the title.
240     */
241    public abstract FragmentTransaction setBreadCrumbTitle(int res);
242
243    /**
244     * Like {@link #setBreadCrumbTitle(int)} but taking a raw string; this
245     * method is <em>not</em> recommended, as the string can not be changed
246     * later if the locale changes.
247     */
248    public abstract FragmentTransaction setBreadCrumbTitle(CharSequence text);
249
250    /**
251     * Set the short title to show as a bread crumb when this transaction
252     * is on the back stack, as used by {@link FragmentBreadCrumbs}.
253     *
254     * @param res A string resource containing the title.
255     */
256    public abstract FragmentTransaction setBreadCrumbShortTitle(int res);
257
258    /**
259     * Like {@link #setBreadCrumbShortTitle(int)} but taking a raw string; this
260     * method is <em>not</em> recommended, as the string can not be changed
261     * later if the locale changes.
262     */
263    public abstract FragmentTransaction setBreadCrumbShortTitle(CharSequence text);
264
265    /**
266     * Schedules a commit of this transaction.  The commit does
267     * not happen immediately; it will be scheduled as work on the main thread
268     * to be done the next time that thread is ready.
269     *
270     * <p class="note">A transaction can only be committed with this method
271     * prior to its containing activity saving its state.  If the commit is
272     * attempted after that point, an exception will be thrown.  This is
273     * because the state after the commit can be lost if the activity needs to
274     * be restored from its state.  See {@link #commitAllowingStateLoss()} for
275     * situations where it may be okay to lose the commit.</p>
276     *
277     * @return Returns the identifier of this transaction's back stack entry,
278     * if {@link #addToBackStack(String)} had been called.  Otherwise, returns
279     * a negative number.
280     */
281    public abstract int commit();
282
283    /**
284     * Like {@link #commit} but allows the commit to be executed after an
285     * activity's state is saved.  This is dangerous because the commit can
286     * be lost if the activity needs to later be restored from its state, so
287     * this should only be used for cases where it is okay for the UI state
288     * to change unexpectedly on the user.
289     */
290    public abstract int commitAllowingStateLoss();
291}
292