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      1 /*
      2  * Copyright (C) 2006 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.view;
     18 
     19 import android.app.Activity;
     20 import android.content.ComponentName;
     21 import android.content.Intent;
     22 
     23 /**
     24  * Interface for managing the items in a menu.
     25  * <p>
     26  * By default, every Activity supports an options menu of actions or options.
     27  * You can add items to this menu and handle clicks on your additions. The
     28  * easiest way of adding menu items is inflating an XML file into the
     29  * {@link Menu} via {@link MenuInflater}. The easiest way of attaching code to
     30  * clicks is via {@link Activity#onOptionsItemSelected(MenuItem)} and
     31  * {@link Activity#onContextItemSelected(MenuItem)}.
     32  * <p>
     33  * Different menu types support different features:
     34  * <ol>
     35  * <li><b>Context menus</b>: Do not support item shortcuts and item icons.
     36  * <li><b>Options menus</b>: The <b>icon menus</b> do not support item check
     37  * marks and only show the item's
     38  * {@link MenuItem#setTitleCondensed(CharSequence) condensed title}. The
     39  * <b>expanded menus</b> (only available if six or more menu items are visible,
     40  * reached via the 'More' item in the icon menu) do not show item icons, and
     41  * item check marks are discouraged.
     42  * <li><b>Sub menus</b>: Do not support item icons, or nested sub menus.
     43  * </ol>
     44  *
     45  * <div class="special reference">
     46  * <h3>Developer Guides</h3>
     47  * <p>For more information about creating menus, read the
     48  * <a href="{@docRoot}guide/topics/ui/menus.html">Menus</a> developer guide.</p>
     49  * </div>
     50  */
     51 public interface Menu {
     52 
     53     /**
     54      * This is the part of an order integer that the user can provide.
     55      * @hide
     56      */
     57     static final int USER_MASK = 0x0000ffff;
     58     /**
     59      * Bit shift of the user portion of the order integer.
     60      * @hide
     61      */
     62     static final int USER_SHIFT = 0;
     63 
     64     /**
     65      * This is the part of an order integer that supplies the category of the
     66      * item.
     67      * @hide
     68      */
     69     static final int CATEGORY_MASK = 0xffff0000;
     70     /**
     71      * Bit shift of the category portion of the order integer.
     72      * @hide
     73      */
     74     static final int CATEGORY_SHIFT = 16;
     75 
     76     /**
     77      * Value to use for group and item identifier integers when you don't care
     78      * about them.
     79      */
     80     static final int NONE = 0;
     81 
     82     /**
     83      * First value for group and item identifier integers.
     84      */
     85     static final int FIRST = 1;
     86 
     87     // Implementation note: Keep these CATEGORY_* in sync with the category enum
     88     // in attrs.xml
     89 
     90     /**
     91      * Category code for the order integer for items/groups that are part of a
     92      * container -- or/add this with your base value.
     93      */
     94     static final int CATEGORY_CONTAINER = 0x00010000;
     95 
     96     /**
     97      * Category code for the order integer for items/groups that are provided by
     98      * the system -- or/add this with your base value.
     99      */
    100     static final int CATEGORY_SYSTEM = 0x00020000;
    101 
    102     /**
    103      * Category code for the order integer for items/groups that are
    104      * user-supplied secondary (infrequently used) options -- or/add this with
    105      * your base value.
    106      */
    107     static final int CATEGORY_SECONDARY = 0x00030000;
    108 
    109     /**
    110      * Category code for the order integer for items/groups that are
    111      * alternative actions on the data that is currently displayed -- or/add
    112      * this with your base value.
    113      */
    114     static final int CATEGORY_ALTERNATIVE = 0x00040000;
    115 
    116     /**
    117      * Flag for {@link #addIntentOptions}: if set, do not automatically remove
    118      * any existing menu items in the same group.
    119      */
    120     static final int FLAG_APPEND_TO_GROUP = 0x0001;
    121 
    122     /**
    123      * Flag for {@link #performShortcut}: if set, do not close the menu after
    124      * executing the shortcut.
    125      */
    126     static final int FLAG_PERFORM_NO_CLOSE = 0x0001;
    127 
    128     /**
    129      * Flag for {@link #performShortcut(int, KeyEvent, int)}: if set, always
    130      * close the menu after executing the shortcut. Closing the menu also resets
    131      * the prepared state.
    132      */
    133     static final int FLAG_ALWAYS_PERFORM_CLOSE = 0x0002;
    134 
    135     /**
    136      * Add a new item to the menu. This item displays the given title for its
    137      * label.
    138      *
    139      * @param title The text to display for the item.
    140      * @return The newly added menu item.
    141      */
    142     public MenuItem add(CharSequence title);
    143 
    144     /**
    145      * Add a new item to the menu. This item displays the given title for its
    146      * label.
    147      *
    148      * @param titleRes Resource identifier of title string.
    149      * @return The newly added menu item.
    150      */
    151     public MenuItem add(int titleRes);
    152 
    153     /**
    154      * Add a new item to the menu. This item displays the given title for its
    155      * label.
    156      *
    157      * @param groupId The group identifier that this item should be part of.
    158      *        This can be used to define groups of items for batch state
    159      *        changes. Normally use {@link #NONE} if an item should not be in a
    160      *        group.
    161      * @param itemId Unique item ID. Use {@link #NONE} if you do not need a
    162      *        unique ID.
    163      * @param order The order for the item. Use {@link #NONE} if you do not care
    164      *        about the order. See {@link MenuItem#getOrder()}.
    165      * @param title The text to display for the item.
    166      * @return The newly added menu item.
    167      */
    168     public MenuItem add(int groupId, int itemId, int order, CharSequence title);
    169 
    170     /**
    171      * Variation on {@link #add(int, int, int, CharSequence)} that takes a
    172      * string resource identifier instead of the string itself.
    173      *
    174      * @param groupId The group identifier that this item should be part of.
    175      *        This can also be used to define groups of items for batch state
    176      *        changes. Normally use {@link #NONE} if an item should not be in a
    177      *        group.
    178      * @param itemId Unique item ID. Use {@link #NONE} if you do not need a
    179      *        unique ID.
    180      * @param order The order for the item. Use {@link #NONE} if you do not care
    181      *        about the order. See {@link MenuItem#getOrder()}.
    182      * @param titleRes Resource identifier of title string.
    183      * @return The newly added menu item.
    184      */
    185     public MenuItem add(int groupId, int itemId, int order, int titleRes);
    186 
    187     /**
    188      * Add a new sub-menu to the menu. This item displays the given title for
    189      * its label. To modify other attributes on the submenu's menu item, use
    190      * {@link SubMenu#getItem()}.
    191      *
    192      * @param title The text to display for the item.
    193      * @return The newly added sub-menu
    194      */
    195     SubMenu addSubMenu(final CharSequence title);
    196 
    197     /**
    198      * Add a new sub-menu to the menu. This item displays the given title for
    199      * its label. To modify other attributes on the submenu's menu item, use
    200      * {@link SubMenu#getItem()}.
    201      *
    202      * @param titleRes Resource identifier of title string.
    203      * @return The newly added sub-menu
    204      */
    205     SubMenu addSubMenu(final int titleRes);
    206 
    207     /**
    208      * Add a new sub-menu to the menu. This item displays the given
    209      * <var>title</var> for its label. To modify other attributes on the
    210      * submenu's menu item, use {@link SubMenu#getItem()}.
    211      *<p>
    212      * Note that you can only have one level of sub-menus, i.e. you cannnot add
    213      * a subMenu to a subMenu: An {@link UnsupportedOperationException} will be
    214      * thrown if you try.
    215      *
    216      * @param groupId The group identifier that this item should be part of.
    217      *        This can also be used to define groups of items for batch state
    218      *        changes. Normally use {@link #NONE} if an item should not be in a
    219      *        group.
    220      * @param itemId Unique item ID. Use {@link #NONE} if you do not need a
    221      *        unique ID.
    222      * @param order The order for the item. Use {@link #NONE} if you do not care
    223      *        about the order. See {@link MenuItem#getOrder()}.
    224      * @param title The text to display for the item.
    225      * @return The newly added sub-menu
    226      */
    227     SubMenu addSubMenu(final int groupId, final int itemId, int order, final CharSequence title);
    228 
    229     /**
    230      * Variation on {@link #addSubMenu(int, int, int, CharSequence)} that takes
    231      * a string resource identifier for the title instead of the string itself.
    232      *
    233      * @param groupId The group identifier that this item should be part of.
    234      *        This can also be used to define groups of items for batch state
    235      *        changes. Normally use {@link #NONE} if an item should not be in a group.
    236      * @param itemId Unique item ID. Use {@link #NONE} if you do not need a unique ID.
    237      * @param order The order for the item. Use {@link #NONE} if you do not care about the
    238      *        order. See {@link MenuItem#getOrder()}.
    239      * @param titleRes Resource identifier of title string.
    240      * @return The newly added sub-menu
    241      */
    242     SubMenu addSubMenu(int groupId, int itemId, int order, int titleRes);
    243 
    244     /**
    245      * Add a group of menu items corresponding to actions that can be performed
    246      * for a particular Intent. The Intent is most often configured with a null
    247      * action, the data that the current activity is working with, and includes
    248      * either the {@link Intent#CATEGORY_ALTERNATIVE} or
    249      * {@link Intent#CATEGORY_SELECTED_ALTERNATIVE} to find activities that have
    250      * said they would like to be included as optional action. You can, however,
    251      * use any Intent you want.
    252      *
    253      * <p>
    254      * See {@link android.content.pm.PackageManager#queryIntentActivityOptions}
    255      * for more * details on the <var>caller</var>, <var>specifics</var>, and
    256      * <var>intent</var> arguments. The list returned by that function is used
    257      * to populate the resulting menu items.
    258      *
    259      * <p>
    260      * All of the menu items of possible options for the intent will be added
    261      * with the given group and id. You can use the group to control ordering of
    262      * the items in relation to other items in the menu. Normally this function
    263      * will automatically remove any existing items in the menu in the same
    264      * group and place a divider above and below the added items; this behavior
    265      * can be modified with the <var>flags</var> parameter. For each of the
    266      * generated items {@link MenuItem#setIntent} is called to associate the
    267      * appropriate Intent with the item; this means the activity will
    268      * automatically be started for you without having to do anything else.
    269      *
    270      * @param groupId The group identifier that the items should be part of.
    271      *        This can also be used to define groups of items for batch state
    272      *        changes. Normally use {@link #NONE} if the items should not be in
    273      *        a group.
    274      * @param itemId Unique item ID. Use {@link #NONE} if you do not need a
    275      *        unique ID.
    276      * @param order The order for the items. Use {@link #NONE} if you do not
    277      *        care about the order. See {@link MenuItem#getOrder()}.
    278      * @param caller The current activity component name as defined by
    279      *        queryIntentActivityOptions().
    280      * @param specifics Specific items to place first as defined by
    281      *        queryIntentActivityOptions().
    282      * @param intent Intent describing the kinds of items to populate in the
    283      *        list as defined by queryIntentActivityOptions().
    284      * @param flags Additional options controlling how the items are added.
    285      * @param outSpecificItems Optional array in which to place the menu items
    286      *        that were generated for each of the <var>specifics</var> that were
    287      *        requested. Entries may be null if no activity was found for that
    288      *        specific action.
    289      * @return The number of menu items that were added.
    290      *
    291      * @see #FLAG_APPEND_TO_GROUP
    292      * @see MenuItem#setIntent
    293      * @see android.content.pm.PackageManager#queryIntentActivityOptions
    294      */
    295     public int addIntentOptions(int groupId, int itemId, int order,
    296                                 ComponentName caller, Intent[] specifics,
    297                                 Intent intent, int flags, MenuItem[] outSpecificItems);
    298 
    299     /**
    300      * Remove the item with the given identifier.
    301      *
    302      * @param id The item to be removed.  If there is no item with this
    303      *           identifier, nothing happens.
    304      */
    305     public void removeItem(int id);
    306 
    307     /**
    308      * Remove all items in the given group.
    309      *
    310      * @param groupId The group to be removed.  If there are no items in this
    311      *           group, nothing happens.
    312      */
    313     public void removeGroup(int groupId);
    314 
    315     /**
    316      * Remove all existing items from the menu, leaving it empty as if it had
    317      * just been created.
    318      */
    319     public void clear();
    320 
    321     /**
    322      * Control whether a particular group of items can show a check mark.  This
    323      * is similar to calling {@link MenuItem#setCheckable} on all of the menu items
    324      * with the given group identifier, but in addition you can control whether
    325      * this group contains a mutually-exclusive set items.  This should be called
    326      * after the items of the group have been added to the menu.
    327      *
    328      * @param group The group of items to operate on.
    329      * @param checkable Set to true to allow a check mark, false to
    330      *                  disallow.  The default is false.
    331      * @param exclusive If set to true, only one item in this group can be
    332      *                  checked at a time; checking an item will automatically
    333      *                  uncheck all others in the group.  If set to false, each
    334      *                  item can be checked independently of the others.
    335      *
    336      * @see MenuItem#setCheckable
    337      * @see MenuItem#setChecked
    338      */
    339     public void setGroupCheckable(int group, boolean checkable, boolean exclusive);
    340 
    341     /**
    342      * Show or hide all menu items that are in the given group.
    343      *
    344      * @param group The group of items to operate on.
    345      * @param visible If true the items are visible, else they are hidden.
    346      *
    347      * @see MenuItem#setVisible
    348      */
    349     public void setGroupVisible(int group, boolean visible);
    350 
    351     /**
    352      * Enable or disable all menu items that are in the given group.
    353      *
    354      * @param group The group of items to operate on.
    355      * @param enabled If true the items will be enabled, else they will be disabled.
    356      *
    357      * @see MenuItem#setEnabled
    358      */
    359     public void setGroupEnabled(int group, boolean enabled);
    360 
    361     /**
    362      * Return whether the menu currently has item items that are visible.
    363      *
    364      * @return True if there is one or more item visible,
    365      *         else false.
    366      */
    367     public boolean hasVisibleItems();
    368 
    369     /**
    370      * Return the menu item with a particular identifier.
    371      *
    372      * @param id The identifier to find.
    373      *
    374      * @return The menu item object, or null if there is no item with
    375      *         this identifier.
    376      */
    377     public MenuItem findItem(int id);
    378 
    379     /**
    380      * Get the number of items in the menu.  Note that this will change any
    381      * times items are added or removed from the menu.
    382      *
    383      * @return The item count.
    384      */
    385     public int size();
    386 
    387     /**
    388      * Gets the menu item at the given index.
    389      *
    390      * @param index The index of the menu item to return.
    391      * @return The menu item.
    392      * @exception IndexOutOfBoundsException
    393      *                when {@code index < 0 || >= size()}
    394      */
    395     public MenuItem getItem(int index);
    396 
    397     /**
    398      * Closes the menu, if open.
    399      */
    400     public void close();
    401 
    402     /**
    403      * Execute the menu item action associated with the given shortcut
    404      * character.
    405      *
    406      * @param keyCode The keycode of the shortcut key.
    407      * @param event Key event message.
    408      * @param flags Additional option flags or 0.
    409      *
    410      * @return If the given shortcut exists and is shown, returns
    411      *         true; else returns false.
    412      *
    413      * @see #FLAG_PERFORM_NO_CLOSE
    414      */
    415     public boolean performShortcut(int keyCode, KeyEvent event, int flags);
    416 
    417     /**
    418      * Is a keypress one of the defined shortcut keys for this window.
    419      * @param keyCode the key code from {@link KeyEvent} to check.
    420      * @param event the {@link KeyEvent} to use to help check.
    421      */
    422     boolean isShortcutKey(int keyCode, KeyEvent event);
    423 
    424     /**
    425      * Execute the menu item action associated with the given menu identifier.
    426      *
    427      * @param id Identifier associated with the menu item.
    428      * @param flags Additional option flags or 0.
    429      *
    430      * @return If the given identifier exists and is shown, returns
    431      *         true; else returns false.
    432      *
    433      * @see #FLAG_PERFORM_NO_CLOSE
    434      */
    435     public boolean performIdentifierAction(int id, int flags);
    436 
    437 
    438     /**
    439      * Control whether the menu should be running in qwerty mode (alphabetic
    440      * shortcuts) or 12-key mode (numeric shortcuts).
    441      *
    442      * @param isQwerty If true the menu will use alphabetic shortcuts; else it
    443      *                 will use numeric shortcuts.
    444      */
    445     public void setQwertyMode(boolean isQwerty);
    446 }
    447 
    448