storage_access_framework

SAF (Storage Access Framework)

1. intro

可以提供本地/云端的DocumentsProvider

Google guide https://developer.android.com/guide/topics/providers/document-provider.html

api:

prebuilts/sdk/api/19.txt

2. 系统包含3部分：

• DocumentsProvider

  继承DocumentsProvider的类，作为provider

• Client app

  发intent (ACTION_OPEN_DOCUMENT and/or ACTION_CREATE_DOCUMENT)

• Picker

  一个UI，让用户选文件,系统默认有DocumentsUI.apk

3. providers

系统内置的DocumentsProvider

1. DownloadStorageProvider
2. ExternalStorageProvider
3. MediaDocumentsProvider

系统的sample provider:

4. VaultProvider

    development/samples/Vault/src/com/example/android/vault/VaultProvider.java

5. MyCloudProvider

    development/samples/browseable/StorageProvider/src/com.example.android.storageprovider/MyCloudProvider.java

6. CTS test provider

    cts/hostsidetests/appsecurity/test-apps/DocumentProvider

4. client samplese

samples/ApiDemos/src/com/example/android/apis/content/DocumentsSample.java
samples/browseable/StorageClient/src/com.example.android.storageclient

5. client实测

intent

Starting: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] cmp=org.cfig/.app.saf.SAFActivity }

NG:(image with GMS)

I/ActivityManager(  550): START u0 {act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=org.cfig/.app.saf.SAFActivity} from uid 0 on display 0

I/ActivityManager(  550): START u0 {act=android.intent.action.OPEN_DOCUMENT cat=[android.intent.category.OPENABLE] typ=*/* cmp=com.google.android.tv.frameworkpackagestubs/.Stubs$DocumentsStub} from uid 10066 on display 0

GOOD:(image with AOSP only)

I/ActivityManager( 1217): START u0 {flg=0x10000000 cmp=org.cfig/.app.saf.SAFActivity} from uid 0 on display 0

I/ActivityManager( 1217): START u0 {act=android.intent.action.OPEN_DOCUMENT cat=[android.intent.category.OPENABLE] typ=*/* cmp=com.android.documentsui/.DocumentsActivity} from uid 10038 on display 0

使用android.intent.action.OPEN_DOCUMENT，默认打开DocumentsUI.apk (frameworks/base/packages/DocumentsUI)

代码

int READ_REQUEST_CODE = 42;
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("*/*");
intent.setPackage("com.android.documentsui");
startActivityForResult(intent, READ_REQUEST_CODE);

解释

intent.setType(): ogg files "audio/ogg",any files "*/*", imgags "image/*"
intent.setPackage(): 不设会走到GMS里面，然后会"no app to handle the intent"