Fix the problem when video file in res/raw file can be played.

[JeffMony]

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[REQUIRED] Use case description

When I create a raw folder in res folder, I save test.mp4 in res/raw/test.mp4,
I want to play the raw video file with : android.resource schema
But exoplayer cannot play the android.resource schema file

Proposed solution

Author: JeffMony <jeffmony@163.com>
Date:   Tue Sep 8 14:56:25 2020 +0800

    Fix the problem when video file in res/raw file can be played.
    
    Signed-off-by: JeffMony <jeffmony@163.com>

diff --git a/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultDataSource.java b/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultDataSource.java
index afef3e676..582a53b02 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultDataSource.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultDataSource.java
@@ -58,6 +58,7 @@ public final class DefaultDataSource implements DataSource {
   private static final String SCHEME_RTMP = "rtmp";
   private static final String SCHEME_UDP = "udp";
   private static final String SCHEME_RAW = RawResourceDataSource.RAW_RESOURCE_SCHEME;
+  private static final String SCHEME_ANDROID_RESOURCE = RawResourceDataSource.ANDROID_RESOURCE_SCHEME;
 
   private final Context context;
   private final List<TransferListener> transferListeners;
@@ -169,7 +170,7 @@ public final class DefaultDataSource implements DataSource {
       dataSource = getUdpDataSource();
     } else if (DataSchemeDataSource.SCHEME_DATA.equals(scheme)) {
       dataSource = getDataSchemeDataSource();
-    } else if (SCHEME_RAW.equals(scheme)) {
+    } else if (SCHEME_RAW.equals(scheme) || SCHEME_ANDROID_RESOURCE.equals(scheme)) {
       dataSource = getRawResourceDataSource();
     } else {
       dataSource = baseDataSource;
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/upstream/RawResourceDataSource.java b/library/core/src/main/java/com/google/android/exoplayer2/upstream/RawResourceDataSource.java
index 0595cb84b..4c7c55d85 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/RawResourceDataSource.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/RawResourceDataSource.java
@@ -65,6 +65,7 @@ public final class RawResourceDataSource extends BaseDataSource {
 
   /** The scheme part of a raw resource URI. */
   public static final String RAW_RESOURCE_SCHEME = "rawresource";
+  public static final String ANDROID_RESOURCE_SCHEME = "android.resource";
 
   private final Resources resources;
 
@@ -87,7 +88,8 @@ public final class RawResourceDataSource extends BaseDataSource {
     try {
       Uri uri = dataSpec.uri;
       this.uri = uri;
-      if (!TextUtils.equals(RAW_RESOURCE_SCHEME, uri.getScheme())) {
+      if (!TextUtils.equals(RAW_RESOURCE_SCHEME, uri.getScheme()) &&
+          !TextUtils.equals(ANDROID_RESOURCE_SCHEME, uri.getScheme())) {
         throw new RawResourceDataSourceException("URI must use scheme " + RAW_RESOURCE_SCHEME);
       }
 

Alternatives considered

A clear and concise description of any alternative solutions you considered,
if applicable.

[JeffMony]

@ojw28 Could you check the feature?

[JeffMony]

@ojw28 Could you check the feature?

Yes, I have checked it with many phones, such as Huawei/Vivo/Oppo/Mi Phone.

[JeffMony]

@ojw28
https://github.com/JeffMony/PlayerSDK/blob/master/files/exoplayer-rawtest.jpg
This is the patch

[kim-vde]

Can you explain why you want the scheme to be "android.resource"? Can you use RawResourceDataSource.buildRawResourceUri(R.raw.filename) to build the URI?

[JeffMony]

@ojw28
I use the android.resource schema for the following reason:
Android platform support android.resource schema, for example, http://androidxref.com/9.0.0_r3/xref/frameworks/base/core/java/android/content/ContentResolver.java#190
`
public static final String SCHEME_ANDROID_RESOURCE = "android.resource";

96 public final @nullable InputStream openInputStream(@nonnull Uri uri)
997 throws FileNotFoundException {
998 Preconditions.checkNotNull(uri, "uri");
999 String scheme = uri.getScheme();
1000 if (SCHEME_ANDROID_RESOURCE.equals(scheme)) {
1001 // Note: left here to avoid breaking compatibility. May be removed
1002 // with sufficient testing.
1003 OpenResourceIdResult r = getResourceId(uri);
1004 try {
1005 InputStream stream = r.r.openRawResource(r.id);
1006 return stream;
1007 } catch (Resources.NotFoundException ex) {
1008 throw new FileNotFoundException("Resource does not exist: " + uri);
1009 }
1010 } else if (SCHEME_FILE.equals(scheme)) {
1011 // Note: left here to avoid breaking compatibility. May be removed
1012 // with sufficient testing.
1013 return new FileInputStream(uri.getPath());
1014 } else {
1015 AssetFileDescriptor fd = openAssetFileDescriptor(uri, "r", null);
1016 try {
1017 return fd != null ? fd.createInputStream() : null;
1018 } catch (IOException e) {
1019 throw new FileNotFoundException("Unable to create stream");
1020 }
1021 }
1022 }
`

ExoPlayer is a universal player, it should support the android platform standard schema such as android.resource

[JeffMony]

@kim-vde The reason

[ojw28]

This is equivalent to [Internal ref: b/162842184]. We should probably just make the changes documented in #6 of the internal issue.

[JeffMony]

This is equivalent to [Internal ref: b/162842184]. We should probably just make the changes documented in #6 of the internal issue.

So , will you submit this change to ExoPlayer project ?

[kim-vde]

Yes, it is work in progress.