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      1 /*
      2  * Copyright (C) 2012 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.hardware.display;
     18 
     19 import android.annotation.NonNull;
     20 import android.annotation.Nullable;
     21 import android.content.Context;
     22 import android.media.projection.MediaProjection;
     23 import android.os.Handler;
     24 import android.util.SparseArray;
     25 import android.view.Display;
     26 import android.view.Surface;
     27 
     28 import java.util.ArrayList;
     29 
     30 /**
     31  * Manages the properties of attached displays.
     32  * <p>
     33  * Get an instance of this class by calling
     34  * {@link android.content.Context#getSystemService(java.lang.String)
     35  * Context.getSystemService()} with the argument
     36  * {@link android.content.Context#DISPLAY_SERVICE}.
     37  * </p>
     38  */
     39 public final class DisplayManager {
     40     private static final String TAG = "DisplayManager";
     41     private static final boolean DEBUG = false;
     42 
     43     private final Context mContext;
     44     private final DisplayManagerGlobal mGlobal;
     45 
     46     private final Object mLock = new Object();
     47     private final SparseArray<Display> mDisplays = new SparseArray<Display>();
     48 
     49     private final ArrayList<Display> mTempDisplays = new ArrayList<Display>();
     50 
     51     /**
     52      * Broadcast receiver that indicates when the Wifi display status changes.
     53      * <p>
     54      * The status is provided as a {@link WifiDisplayStatus} object in the
     55      * {@link #EXTRA_WIFI_DISPLAY_STATUS} extra.
     56      * </p><p>
     57      * This broadcast is only sent to registered receivers and can only be sent by the system.
     58      * </p>
     59      * @hide
     60      */
     61     public static final String ACTION_WIFI_DISPLAY_STATUS_CHANGED =
     62             "android.hardware.display.action.WIFI_DISPLAY_STATUS_CHANGED";
     63 
     64     /**
     65      * Contains a {@link WifiDisplayStatus} object.
     66      * @hide
     67      */
     68     public static final String EXTRA_WIFI_DISPLAY_STATUS =
     69             "android.hardware.display.extra.WIFI_DISPLAY_STATUS";
     70 
     71     /**
     72      * Display category: Presentation displays.
     73      * <p>
     74      * This category can be used to identify secondary displays that are suitable for
     75      * use as presentation displays such as HDMI or Wireless displays.  Applications
     76      * may automatically project their content to presentation displays to provide
     77      * richer second screen experiences.
     78      * </p>
     79      *
     80      * @see android.app.Presentation
     81      * @see Display#FLAG_PRESENTATION
     82      * @see #getDisplays(String)
     83      */
     84     public static final String DISPLAY_CATEGORY_PRESENTATION =
     85             "android.hardware.display.category.PRESENTATION";
     86 
     87     /**
     88      * Virtual display flag: Create a public display.
     89      *
     90      * <h3>Public virtual displays</h3>
     91      * <p>
     92      * When this flag is set, the virtual display is public.
     93      * </p><p>
     94      * A public virtual display behaves just like most any other display that is connected
     95      * to the system such as an HDMI or Wireless display.  Applications can open
     96      * windows on the display and the system may mirror the contents of other displays
     97      * onto it.
     98      * </p><p>
     99      * Creating a public virtual display that isn't restricted to own-content only implicitly
    100      * creates an auto-mirroring display. See {@link #VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR} for
    101      * restrictions on who is allowed to create an auto-mirroring display.
    102      * </p>
    103      *
    104      * <h3>Private virtual displays</h3>
    105      * <p>
    106      * When this flag is not set, the virtual display is private as defined by the
    107      * {@link Display#FLAG_PRIVATE} display flag.
    108      * </p>
    109      *
    110      * <p>
    111      * A private virtual display belongs to the application that created it.
    112      * Only the a owner of a private virtual display is allowed to place windows upon it.
    113      * The private virtual display also does not participate in display mirroring: it will
    114      * neither receive mirrored content from another display nor allow its own content to
    115      * be mirrored elsewhere.  More precisely, the only processes that are allowed to
    116      * enumerate or interact with the private display are those that have the same UID as the
    117      * application that originally created the private virtual display.
    118      * </p>
    119      *
    120      * @see #createVirtualDisplay
    121      * @see #VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY
    122      * @see #VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR
    123      */
    124     public static final int VIRTUAL_DISPLAY_FLAG_PUBLIC = 1 << 0;
    125 
    126     /**
    127      * Virtual display flag: Create a presentation display.
    128      *
    129      * <h3>Presentation virtual displays</h3>
    130      * <p>
    131      * When this flag is set, the virtual display is registered as a presentation
    132      * display in the {@link #DISPLAY_CATEGORY_PRESENTATION presentation display category}.
    133      * Applications may automatically project their content to presentation displays
    134      * to provide richer second screen experiences.
    135      * </p>
    136      *
    137      * <h3>Non-presentation virtual displays</h3>
    138      * <p>
    139      * When this flag is not set, the virtual display is not registered as a presentation
    140      * display.  Applications can still project their content on the display but they
    141      * will typically not do so automatically.  This option is appropriate for
    142      * more special-purpose displays.
    143      * </p>
    144      *
    145      * @see android.app.Presentation
    146      * @see #createVirtualDisplay
    147      * @see #DISPLAY_CATEGORY_PRESENTATION
    148      * @see Display#FLAG_PRESENTATION
    149      */
    150     public static final int VIRTUAL_DISPLAY_FLAG_PRESENTATION = 1 << 1;
    151 
    152     /**
    153      * Virtual display flag: Create a secure display.
    154      *
    155      * <h3>Secure virtual displays</h3>
    156      * <p>
    157      * When this flag is set, the virtual display is considered secure as defined
    158      * by the {@link Display#FLAG_SECURE} display flag.  The caller promises to take
    159      * reasonable measures, such as over-the-air encryption, to prevent the contents
    160      * of the display from being intercepted or recorded on a persistent medium.
    161      * </p><p>
    162      * Creating a secure virtual display requires the
    163      * {@link android.Manifest.permission#CAPTURE_SECURE_VIDEO_OUTPUT} permission.
    164      * This permission is reserved for use by system components and is not available to
    165      * third-party applications.
    166      * </p>
    167      *
    168      * <h3>Non-secure virtual displays</h3>
    169      * <p>
    170      * When this flag is not set, the virtual display is considered unsecure.
    171      * The content of secure windows will be blanked if shown on this display.
    172      * </p>
    173      *
    174      * @see Display#FLAG_SECURE
    175      * @see #createVirtualDisplay
    176      */
    177     public static final int VIRTUAL_DISPLAY_FLAG_SECURE = 1 << 2;
    178 
    179     /**
    180      * Virtual display flag: Only show this display's own content; do not mirror
    181      * the content of another display.
    182      *
    183      * <p>
    184      * This flag is used in conjunction with {@link #VIRTUAL_DISPLAY_FLAG_PUBLIC}.
    185      * Ordinarily public virtual displays will automatically mirror the content of the
    186      * default display if they have no windows of their own.  When this flag is
    187      * specified, the virtual display will only ever show its own content and
    188      * will be blanked instead if it has no windows.
    189      * </p>
    190      *
    191      * <p>
    192      * This flag is mutually exclusive with {@link #VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR}.  If both
    193      * flags are specified then the own-content only behavior will be applied.
    194      * </p>
    195      *
    196      * <p>
    197      * This behavior of this flag is implied whenever neither {@link #VIRTUAL_DISPLAY_FLAG_PUBLIC}
    198      * nor {@link #VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR} have been set.  This flag is only required to
    199      * override the default behavior when creating a public display.
    200      * </p>
    201      *
    202      * @see #createVirtualDisplay
    203      */
    204     public static final int VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY = 1 << 3;
    205 
    206 
    207     /**
    208      * Virtual display flag: Allows content to be mirrored on private displays when no content is
    209      * being shown.
    210      *
    211      * <p>
    212      * This flag is mutually exclusive with {@link #VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY}.
    213      * If both flags are specified then the own-content only behavior will be applied.
    214      * </p>
    215      *
    216      * <p>
    217      * The behavior of this flag is implied whenever {@link #VIRTUAL_DISPLAY_FLAG_PUBLIC} is set
    218      * and {@link #VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY} has not been set.   This flag is only
    219      * required to override the default behavior when creating a private display.
    220      * </p>
    221      *
    222      * <p>
    223      * Creating an auto-mirroing virtual display requires the
    224      * {@link android.Manifest.permission#CAPTURE_VIDEO_OUTPUT}
    225      * or {@link android.Manifest.permission#CAPTURE_SECURE_VIDEO_OUTPUT} permission.
    226      * These permissions are reserved for use by system components and are not available to
    227      * third-party applications.
    228      *
    229      * Alternatively, an appropriate {@link MediaProjection} may be used to create an
    230      * auto-mirroring virtual display.
    231      * </p>
    232      *
    233      * @see #createVirtualDisplay
    234      */
    235     public static final int VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR = 1 << 4;
    236 
    237     /** @hide */
    238     public DisplayManager(Context context) {
    239         mContext = context;
    240         mGlobal = DisplayManagerGlobal.getInstance();
    241     }
    242 
    243     /**
    244      * Gets information about a logical display.
    245      *
    246      * The display metrics may be adjusted to provide compatibility
    247      * for legacy applications.
    248      *
    249      * @param displayId The logical display id.
    250      * @return The display object, or null if there is no valid display with the given id.
    251      */
    252     public Display getDisplay(int displayId) {
    253         synchronized (mLock) {
    254             return getOrCreateDisplayLocked(displayId, false /*assumeValid*/);
    255         }
    256     }
    257 
    258     /**
    259      * Gets all currently valid logical displays.
    260      *
    261      * @return An array containing all displays.
    262      */
    263     public Display[] getDisplays() {
    264         return getDisplays(null);
    265     }
    266 
    267     /**
    268      * Gets all currently valid logical displays of the specified category.
    269      * <p>
    270      * When there are multiple displays in a category the returned displays are sorted
    271      * of preference.  For example, if the requested category is
    272      * {@link #DISPLAY_CATEGORY_PRESENTATION} and there are multiple presentation displays
    273      * then the displays are sorted so that the first display in the returned array
    274      * is the most preferred presentation display.  The application may simply
    275      * use the first display or allow the user to choose.
    276      * </p>
    277      *
    278      * @param category The requested display category or null to return all displays.
    279      * @return An array containing all displays sorted by order of preference.
    280      *
    281      * @see #DISPLAY_CATEGORY_PRESENTATION
    282      */
    283     public Display[] getDisplays(String category) {
    284         final int[] displayIds = mGlobal.getDisplayIds();
    285         synchronized (mLock) {
    286             try {
    287                 if (category == null) {
    288                     addAllDisplaysLocked(mTempDisplays, displayIds);
    289                 } else if (category.equals(DISPLAY_CATEGORY_PRESENTATION)) {
    290                     addPresentationDisplaysLocked(mTempDisplays, displayIds, Display.TYPE_WIFI);
    291                     addPresentationDisplaysLocked(mTempDisplays, displayIds, Display.TYPE_HDMI);
    292                     addPresentationDisplaysLocked(mTempDisplays, displayIds, Display.TYPE_OVERLAY);
    293                     addPresentationDisplaysLocked(mTempDisplays, displayIds, Display.TYPE_VIRTUAL);
    294                 }
    295                 return mTempDisplays.toArray(new Display[mTempDisplays.size()]);
    296             } finally {
    297                 mTempDisplays.clear();
    298             }
    299         }
    300     }
    301 
    302     private void addAllDisplaysLocked(ArrayList<Display> displays, int[] displayIds) {
    303         for (int i = 0; i < displayIds.length; i++) {
    304             Display display = getOrCreateDisplayLocked(displayIds[i], true /*assumeValid*/);
    305             if (display != null) {
    306                 displays.add(display);
    307             }
    308         }
    309     }
    310 
    311     private void addPresentationDisplaysLocked(
    312             ArrayList<Display> displays, int[] displayIds, int matchType) {
    313         for (int i = 0; i < displayIds.length; i++) {
    314             Display display = getOrCreateDisplayLocked(displayIds[i], true /*assumeValid*/);
    315             if (display != null
    316                     && (display.getFlags() & Display.FLAG_PRESENTATION) != 0
    317                     && display.getType() == matchType) {
    318                 displays.add(display);
    319             }
    320         }
    321     }
    322 
    323     private Display getOrCreateDisplayLocked(int displayId, boolean assumeValid) {
    324         Display display = mDisplays.get(displayId);
    325         if (display == null) {
    326             display = mGlobal.getCompatibleDisplay(displayId,
    327                     mContext.getDisplayAdjustments(displayId));
    328             if (display != null) {
    329                 mDisplays.put(displayId, display);
    330             }
    331         } else if (!assumeValid && !display.isValid()) {
    332             display = null;
    333         }
    334         return display;
    335     }
    336 
    337     /**
    338      * Registers an display listener to receive notifications about when
    339      * displays are added, removed or changed.
    340      *
    341      * @param listener The listener to register.
    342      * @param handler The handler on which the listener should be invoked, or null
    343      * if the listener should be invoked on the calling thread's looper.
    344      *
    345      * @see #unregisterDisplayListener
    346      */
    347     public void registerDisplayListener(DisplayListener listener, Handler handler) {
    348         mGlobal.registerDisplayListener(listener, handler);
    349     }
    350 
    351     /**
    352      * Unregisters a display listener.
    353      *
    354      * @param listener The listener to unregister.
    355      *
    356      * @see #registerDisplayListener
    357      */
    358     public void unregisterDisplayListener(DisplayListener listener) {
    359         mGlobal.unregisterDisplayListener(listener);
    360     }
    361 
    362     /**
    363      * Starts scanning for available Wifi displays.
    364      * The results are sent as a {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED} broadcast.
    365      * <p>
    366      * Calls to this method nest and must be matched by an equal number of calls to
    367      * {@link #stopWifiDisplayScan()}.
    368      * </p><p>
    369      * Requires {@link android.Manifest.permission#CONFIGURE_WIFI_DISPLAY}.
    370      * </p>
    371      *
    372      * @hide
    373      */
    374     public void startWifiDisplayScan() {
    375         mGlobal.startWifiDisplayScan();
    376     }
    377 
    378     /**
    379      * Stops scanning for available Wifi displays.
    380      * <p>
    381      * Requires {@link android.Manifest.permission#CONFIGURE_WIFI_DISPLAY}.
    382      * </p>
    383      *
    384      * @hide
    385      */
    386     public void stopWifiDisplayScan() {
    387         mGlobal.stopWifiDisplayScan();
    388     }
    389 
    390     /**
    391      * Connects to a Wifi display.
    392      * The results are sent as a {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED} broadcast.
    393      * <p>
    394      * Automatically remembers the display after a successful connection, if not
    395      * already remembered.
    396      * </p><p>
    397      * Requires {@link android.Manifest.permission#CONFIGURE_WIFI_DISPLAY}.
    398      * </p>
    399      *
    400      * @param deviceAddress The MAC address of the device to which we should connect.
    401      * @hide
    402      */
    403     public void connectWifiDisplay(String deviceAddress) {
    404         mGlobal.connectWifiDisplay(deviceAddress);
    405     }
    406 
    407     /** @hide */
    408     public void pauseWifiDisplay() {
    409         mGlobal.pauseWifiDisplay();
    410     }
    411 
    412     /** @hide */
    413     public void resumeWifiDisplay() {
    414         mGlobal.resumeWifiDisplay();
    415     }
    416 
    417     /**
    418      * Disconnects from the current Wifi display.
    419      * The results are sent as a {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED} broadcast.
    420      * @hide
    421      */
    422     public void disconnectWifiDisplay() {
    423         mGlobal.disconnectWifiDisplay();
    424     }
    425 
    426     /**
    427      * Renames a Wifi display.
    428      * <p>
    429      * The display must already be remembered for this call to succeed.  In other words,
    430      * we must already have successfully connected to the display at least once and then
    431      * not forgotten it.
    432      * </p><p>
    433      * Requires {@link android.Manifest.permission#CONFIGURE_WIFI_DISPLAY}.
    434      * </p>
    435      *
    436      * @param deviceAddress The MAC address of the device to rename.
    437      * @param alias The alias name by which to remember the device, or null
    438      * or empty if no alias should be used.
    439      * @hide
    440      */
    441     public void renameWifiDisplay(String deviceAddress, String alias) {
    442         mGlobal.renameWifiDisplay(deviceAddress, alias);
    443     }
    444 
    445     /**
    446      * Forgets a previously remembered Wifi display.
    447      * <p>
    448      * Automatically disconnects from the display if currently connected to it.
    449      * </p><p>
    450      * Requires {@link android.Manifest.permission#CONFIGURE_WIFI_DISPLAY}.
    451      * </p>
    452      *
    453      * @param deviceAddress The MAC address of the device to forget.
    454      * @hide
    455      */
    456     public void forgetWifiDisplay(String deviceAddress) {
    457         mGlobal.forgetWifiDisplay(deviceAddress);
    458     }
    459 
    460     /**
    461      * Gets the current Wifi display status.
    462      * Watch for changes in the status by registering a broadcast receiver for
    463      * {@link #ACTION_WIFI_DISPLAY_STATUS_CHANGED}.
    464      *
    465      * @return The current Wifi display status.
    466      * @hide
    467      */
    468     public WifiDisplayStatus getWifiDisplayStatus() {
    469         return mGlobal.getWifiDisplayStatus();
    470     }
    471 
    472     /**
    473      * Creates a virtual display.
    474      *
    475      * @see #createVirtualDisplay(String, int, int, int, Surface, int, VirtualDisplay.Callback)
    476      */
    477     public VirtualDisplay createVirtualDisplay(@NonNull String name,
    478             int width, int height, int densityDpi, @Nullable Surface surface, int flags) {
    479         return createVirtualDisplay(name, width, height, densityDpi, surface, flags, null, null);
    480     }
    481 
    482     /**
    483      * Creates a virtual display.
    484      * <p>
    485      * The content of a virtual display is rendered to a {@link Surface} provided
    486      * by the application.
    487      * </p><p>
    488      * The virtual display should be {@link VirtualDisplay#release released}
    489      * when no longer needed.  Because a virtual display renders to a surface
    490      * provided by the application, it will be released automatically when the
    491      * process terminates and all remaining windows on it will be forcibly removed.
    492      * </p><p>
    493      * The behavior of the virtual display depends on the flags that are provided
    494      * to this method.  By default, virtual displays are created to be private,
    495      * non-presentation and unsecure.  Permissions may be required to use certain flags.
    496      * </p><p>
    497      * As of {@link android.os.Build.VERSION_CODES#KITKAT_WATCH}, the surface may
    498      * be attached or detached dynamically using {@link VirtualDisplay#setSurface}.
    499      * Previously, the surface had to be non-null when {@link #createVirtualDisplay}
    500      * was called and could not be changed for the lifetime of the display.
    501      * </p><p>
    502      * Detaching the surface that backs a virtual display has a similar effect to
    503      * turning off the screen.
    504      * </p>
    505      *
    506      * @param name The name of the virtual display, must be non-empty.
    507      * @param width The width of the virtual display in pixels, must be greater than 0.
    508      * @param height The height of the virtual display in pixels, must be greater than 0.
    509      * @param densityDpi The density of the virtual display in dpi, must be greater than 0.
    510      * @param surface The surface to which the content of the virtual display should
    511      * be rendered, or null if there is none initially.
    512      * @param flags A combination of virtual display flags:
    513      * {@link #VIRTUAL_DISPLAY_FLAG_PUBLIC}, {@link #VIRTUAL_DISPLAY_FLAG_PRESENTATION},
    514      * {@link #VIRTUAL_DISPLAY_FLAG_SECURE}, {@link #VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY},
    515      * or {@link #VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR}.
    516      * @param callback Callback to call when the state of the {@link VirtualDisplay} changes
    517      * @param handler The handler on which the listener should be invoked, or null
    518      * if the listener should be invoked on the calling thread's looper.
    519      * @return The newly created virtual display, or null if the application could
    520      * not create the virtual display.
    521      *
    522      * @throws SecurityException if the caller does not have permission to create
    523      * a virtual display with the specified flags.
    524      */
    525     public VirtualDisplay createVirtualDisplay(@NonNull String name,
    526             int width, int height, int densityDpi, @Nullable Surface surface, int flags,
    527             @Nullable VirtualDisplay.Callback callback, @Nullable Handler handler) {
    528         return createVirtualDisplay(null,
    529                 name, width, height, densityDpi, surface, flags, callback, handler);
    530     }
    531 
    532     /** @hide */
    533     public VirtualDisplay createVirtualDisplay(@Nullable MediaProjection projection,
    534             @NonNull String name, int width, int height, int densityDpi, @Nullable Surface surface,
    535             int flags, @Nullable VirtualDisplay.Callback callback, @Nullable Handler handler) {
    536         return mGlobal.createVirtualDisplay(mContext, projection,
    537                 name, width, height, densityDpi, surface, flags, callback, handler);
    538     }
    539 
    540     /**
    541      * Listens for changes in available display devices.
    542      */
    543     public interface DisplayListener {
    544         /**
    545          * Called whenever a logical display has been added to the system.
    546          * Use {@link DisplayManager#getDisplay} to get more information about
    547          * the display.
    548          *
    549          * @param displayId The id of the logical display that was added.
    550          */
    551         void onDisplayAdded(int displayId);
    552 
    553         /**
    554          * Called whenever a logical display has been removed from the system.
    555          *
    556          * @param displayId The id of the logical display that was removed.
    557          */
    558         void onDisplayRemoved(int displayId);
    559 
    560         /**
    561          * Called whenever the properties of a logical display have changed.
    562          *
    563          * @param displayId The id of the logical display that changed.
    564          */
    565         void onDisplayChanged(int displayId);
    566     }
    567 }
    568