am 21de56a9: Add directory selection to DocumentsProvider.

* commit '21de56a94668e0fda1b8bb4ee4f99a09b40d28fd':
  Add directory selection to DocumentsProvider.

8 files changed, 226 insertions, 291 deletions

diff --git a/packages/DocumentsUI/AndroidManifest.xml b/packages/DocumentsUI/AndroidManifest.xml
index 6b77a7c..159ee66 100644
--- a/packages/DocumentsUI/AndroidManifest.xml
+++ b/packages/DocumentsUI/AndroidManifest.xml
@@ -9,18 +9,17 @@
         android:label="@string/app_label"
         android:supportsRtl="true">
 
-        <!-- TODO: allow rotation when state saving is in better shape -->
         <activity
             android:name=".DocumentsActivity"
             android:theme="@style/Theme"
             android:icon="@drawable/ic_doc_text">
-            <intent-filter android:priority="100">
+            <intent-filter>
                 <action android:name="android.intent.action.OPEN_DOCUMENT" />
                 <category android:name="android.intent.category.DEFAULT" />
                 <category android:name="android.intent.category.OPENABLE" />
                 <data android:mimeType="*/*" />
             </intent-filter>
-            <intent-filter android:priority="100">
+            <intent-filter>
                 <action android:name="android.intent.action.CREATE_DOCUMENT" />
                 <category android:name="android.intent.category.DEFAULT" />
                 <category android:name="android.intent.category.OPENABLE" />
@@ -33,6 +32,10 @@
                 <data android:mimeType="*/*" />
             </intent-filter>
             <intent-filter>
+                <action android:name="android.intent.action.PICK_DIRECTORY" />
+                <category android:name="android.intent.category.DEFAULT" />
+            </intent-filter>
+            <intent-filter>
                 <action android:name="android.provider.action.MANAGE_ROOT" />
                 <category android:name="android.intent.category.DEFAULT" />
                 <data android:mimeType="vnd.android.document/root" />
@@ -57,14 +60,5 @@
                 <data android:scheme="package" />
             </intent-filter>
         </receiver>
-
-        <!-- TODO: remove when we have real clients -->
-        <activity android:name=".TestActivity" android:enabled="false">
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN" />
-                <category android:name="android.intent.category.DEFAULT" />
-                <category android:name="android.intent.category.LAUNCHER" />
-            </intent-filter>
-        </activity>
     </application>
 </manifest>
diff --git a/packages/DocumentsUI/res/layout/fragment_pick.xml b/packages/DocumentsUI/res/layout/fragment_pick.xml
new file mode 100644
index 0000000..4a2fd03
--- /dev/null
+++ b/packages/DocumentsUI/res/layout/fragment_pick.xml
@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical">
+
+    <!-- Le sigh, this really should be an asset -->
+    <View
+        android:layout_width="match_parent"
+        android:layout_height="1dp"
+        android:background="#ccc" />
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:baselineAligned="false"
+        android:gravity="center_vertical"
+        android:background="#ddd"
+        android:minHeight="?android:attr/listPreferredItemHeightSmall">
+
+        <Button
+            android:id="@android:id/button1"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:background="?android:attr/selectableItemBackground"
+            android:textAppearance="?android:attr/textAppearanceSmall"
+            android:textAllCaps="false"
+            android:padding="8dp" />
+
+    </LinearLayout>
+
+</LinearLayout>
diff --git a/packages/DocumentsUI/res/values/strings.xml b/packages/DocumentsUI/res/values/strings.xml
index 92c30ba..c1a9d72 100644
--- a/packages/DocumentsUI/res/values/strings.xml
+++ b/packages/DocumentsUI/res/values/strings.xml
@@ -44,6 +44,8 @@
     <string name="menu_share">Share</string>
     <!-- Menu item title that deletes the selected documents [CHAR LIMIT=24] -->
     <string name="menu_delete">Delete</string>
+    <!-- Menu item title that selects the current directory [CHAR LIMIT=48] -->
+    <string name="menu_select">Select \"<xliff:g id="directory" example="My Directory">^1</xliff:g>\"</string>
 
     <!-- Action mode title summarizing the number of documents selected [CHAR LIMIT=32] -->
     <string name="mode_selected_count"><xliff:g id="count" example="3">%1$d</xliff:g> selected</string>
diff --git a/packages/DocumentsUI/src/com/android/documentsui/DocumentsActivity.java b/packages/DocumentsUI/src/com/android/documentsui/DocumentsActivity.java
index 4212e96..9f76991 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/DocumentsActivity.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/DocumentsActivity.java
@@ -24,6 +24,7 @@ import static com.android.documentsui.DocumentsActivity.State.ACTION_CREATE;
 import static com.android.documentsui.DocumentsActivity.State.ACTION_GET_CONTENT;
 import static com.android.documentsui.DocumentsActivity.State.ACTION_MANAGE;
 import static com.android.documentsui.DocumentsActivity.State.ACTION_OPEN;
+import static com.android.documentsui.DocumentsActivity.State.ACTION_PICK_DIRECTORY;
 import static com.android.documentsui.DocumentsActivity.State.MODE_GRID;
 import static com.android.documentsui.DocumentsActivity.State.MODE_LIST;
 
@@ -202,6 +203,8 @@ public class DocumentsActivity extends Activity {
             final String mimeType = getIntent().getType();
             final String title = getIntent().getStringExtra(Intent.EXTRA_TITLE);
             SaveFragment.show(getFragmentManager(), mimeType, title);
+        } else if (mState.action == ACTION_PICK_DIRECTORY) {
+            PickFragment.show(getFragmentManager());
         }
 
         if (mState.action == ACTION_GET_CONTENT) {
@@ -209,7 +212,8 @@ public class DocumentsActivity extends Activity {
             moreApps.setComponent(null);
             moreApps.setPackage(null);
             RootsFragment.show(getFragmentManager(), moreApps);
-        } else if (mState.action == ACTION_OPEN || mState.action == ACTION_CREATE) {
+        } else if (mState.action == ACTION_OPEN || mState.action == ACTION_CREATE
+                || mState.action == ACTION_PICK_DIRECTORY) {
             RootsFragment.show(getFragmentManager(), null);
         }
 
@@ -236,6 +240,8 @@ public class DocumentsActivity extends Activity {
             mState.action = ACTION_CREATE;
         } else if (Intent.ACTION_GET_CONTENT.equals(action)) {
             mState.action = ACTION_GET_CONTENT;
+        } else if (Intent.ACTION_PICK_DIRECTORY.equals(action)) {
+            mState.action = ACTION_PICK_DIRECTORY;
         } else if (DocumentsContract.ACTION_MANAGE_ROOT.equals(action)) {
             mState.action = ACTION_MANAGE;
         }
@@ -434,7 +440,8 @@ public class DocumentsActivity extends Activity {
             actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
             actionBar.setIcon(new ColorDrawable());
 
-            if (mState.action == ACTION_OPEN || mState.action == ACTION_GET_CONTENT) {
+            if (mState.action == ACTION_OPEN || mState.action == ACTION_GET_CONTENT
+                    || mState.action == ACTION_PICK_DIRECTORY) {
                 actionBar.setTitle(R.string.title_open);
             } else if (mState.action == ACTION_CREATE) {
                 actionBar.setTitle(R.string.title_save);
@@ -576,7 +583,7 @@ public class DocumentsActivity extends Activity {
         sortSize.setVisible(mState.showSize);
 
         final boolean searchVisible;
-        if (mState.action == ACTION_CREATE) {
+        if (mState.action == ACTION_CREATE || mState.action == ACTION_PICK_DIRECTORY) {
             createDir.setVisible(cwd != null && cwd.isCreateSupported());
             searchVisible = false;
 
@@ -586,7 +593,9 @@ public class DocumentsActivity extends Activity {
                 list.setVisible(false);
             }
 
-            SaveFragment.get(fm).setSaveEnabled(cwd != null && cwd.isCreateSupported());
+            if (mState.action == ACTION_CREATE) {
+                SaveFragment.get(fm).setSaveEnabled(cwd != null && cwd.isCreateSupported());
+            }
         } else {
             createDir.setVisible(false);
 
@@ -819,7 +828,7 @@ public class DocumentsActivity extends Activity {
 
         if (cwd == null) {
             // No directory means recents
-            if (mState.action == ACTION_CREATE) {
+            if (mState.action == ACTION_CREATE || mState.action == ACTION_PICK_DIRECTORY) {
                 RecentsCreateFragment.show(fm);
             } else {
                 DirectoryFragment.showRecentsOpen(fm, anim);
@@ -848,6 +857,15 @@ public class DocumentsActivity extends Activity {
             }
         }
 
+        if (mState.action == ACTION_PICK_DIRECTORY) {
+            final PickFragment pick = PickFragment.get(fm);
+            if (pick != null) {
+                final CharSequence displayName = (mState.stack.size() <= 1) ? root.title
+                        : cwd.displayName;
+                pick.setPickTarget(cwd, displayName);
+            }
+        }
+
         final RootsFragment roots = RootsFragment.get(fm);
         if (roots != null) {
             roots.onCurrentRootChanged();
@@ -1002,12 +1020,18 @@ public class DocumentsActivity extends Activity {
         new CreateFinishTask(mimeType, displayName).executeOnExecutor(getCurrentExecutor());
     }
 
+    public void onPickRequested(DocumentInfo pickTarget) {
+        final Uri viaUri = DocumentsContract.buildViaUri(pickTarget.authority,
+                pickTarget.documentId);
+        new PickFinishTask(viaUri).executeOnExecutor(getCurrentExecutor());
+    }
+
     private void saveStackBlocking() {
         final ContentResolver resolver = getContentResolver();
         final ContentValues values = new ContentValues();
 
         final byte[] rawStack = DurableUtils.writeToArrayOrNull(mState.stack);
-        if (mState.action == ACTION_CREATE) {
+        if (mState.action == ACTION_CREATE || mState.action == ACTION_PICK_DIRECTORY) {
             // Remember stack for last create
             values.clear();
             values.put(RecentColumns.KEY, mState.stack.buildKey());
@@ -1040,6 +1064,11 @@ public class DocumentsActivity extends Activity {
 
         if (mState.action == ACTION_GET_CONTENT) {
             intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
+        } else if (mState.action == ACTION_PICK_DIRECTORY) {
+            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION
+                    | Intent.FLAG_GRANT_WRITE_URI_PERMISSION
+                    | Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION
+                    | Intent.FLAG_GRANT_PREFIX_URI_PERMISSION);
         } else {
             intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION
                     | Intent.FLAG_GRANT_WRITE_URI_PERMISSION
@@ -1121,6 +1150,25 @@ public class DocumentsActivity extends Activity {
         }
     }
 
+    private class PickFinishTask extends AsyncTask<Void, Void, Void> {
+        private final Uri mUri;
+
+        public PickFinishTask(Uri uri) {
+            mUri = uri;
+        }
+
+        @Override
+        protected Void doInBackground(Void... params) {
+            saveStackBlocking();
+            return null;
+        }
+
+        @Override
+        protected void onPostExecute(Void result) {
+            onFinished(mUri);
+        }
+    }
+
     public static class State implements android.os.Parcelable {
         public int action;
         public String[] acceptMimes;
@@ -1154,7 +1202,8 @@ public class DocumentsActivity extends Activity {
         public static final int ACTION_OPEN = 1;
         public static final int ACTION_CREATE = 2;
         public static final int ACTION_GET_CONTENT = 3;
-        public static final int ACTION_MANAGE = 4;
+        public static final int ACTION_PICK_DIRECTORY = 4;
+        public static final int ACTION_MANAGE = 5;
 
         public static final int MODE_UNKNOWN = 0;
         public static final int MODE_LIST = 1;
diff --git a/packages/DocumentsUI/src/com/android/documentsui/PickFragment.java b/packages/DocumentsUI/src/com/android/documentsui/PickFragment.java
new file mode 100644
index 0000000..a9e488a1
--- /dev/null
+++ b/packages/DocumentsUI/src/com/android/documentsui/PickFragment.java
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.documentsui;
+
+import android.app.Fragment;
+import android.app.FragmentManager;
+import android.app.FragmentTransaction;
+import android.os.Bundle;
+import android.text.TextUtils;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.Button;
+
+import com.android.documentsui.model.DocumentInfo;
+
+import java.util.Locale;
+
+/**
+ * Display pick confirmation bar, usually for selecting a directory.
+ */
+public class PickFragment extends Fragment {
+    public static final String TAG = "PickFragment";
+
+    private DocumentInfo mPickTarget;
+
+    private View mContainer;
+    private Button mPick;
+
+    public static void show(FragmentManager fm) {
+        final PickFragment fragment = new PickFragment();
+
+        final FragmentTransaction ft = fm.beginTransaction();
+        ft.replace(R.id.container_save, fragment, TAG);
+        ft.commitAllowingStateLoss();
+    }
+
+    public static PickFragment get(FragmentManager fm) {
+        return (PickFragment) fm.findFragmentByTag(TAG);
+    }
+
+    @Override
+    public View onCreateView(
+            LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
+        mContainer = inflater.inflate(R.layout.fragment_pick, container, false);
+
+        mPick = (Button) mContainer.findViewById(android.R.id.button1);
+        mPick.setOnClickListener(mPickListener);
+
+        setPickTarget(null, null);
+
+        return mContainer;
+    }
+
+    private View.OnClickListener mPickListener = new View.OnClickListener() {
+        @Override
+        public void onClick(View v) {
+            final DocumentsActivity activity = DocumentsActivity.get(PickFragment.this);
+            activity.onPickRequested(mPickTarget);
+        }
+    };
+
+    public void setPickTarget(DocumentInfo pickTarget, CharSequence displayName) {
+        mPickTarget = pickTarget;
+
+        if (mPickTarget != null) {
+            mContainer.setVisibility(View.VISIBLE);
+            final Locale locale = getResources().getConfiguration().locale;
+            final String raw = getString(R.string.menu_select).toUpperCase(locale);
+            mPick.setText(TextUtils.expandTemplate(raw, displayName));
+        } else {
+            mContainer.setVisibility(View.GONE);
+        }
+    }
+}
diff --git a/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java b/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java
index f1dca1d..933dbe0 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java
@@ -104,7 +104,8 @@ public class RootsCache {
         mRecentsRoot.authority = null;
         mRecentsRoot.rootId = null;
         mRecentsRoot.icon = R.drawable.ic_root_recent;
-        mRecentsRoot.flags = Root.FLAG_LOCAL_ONLY | Root.FLAG_SUPPORTS_CREATE;
+        mRecentsRoot.flags = Root.FLAG_LOCAL_ONLY | Root.FLAG_SUPPORTS_CREATE
+                | Root.FLAG_SUPPORTS_DIR_SELECTION;
         mRecentsRoot.title = mContext.getString(R.string.root_recent);
         mRecentsRoot.availableBytes = -1;
 
@@ -349,12 +350,15 @@ public class RootsCache {
         final List<RootInfo> matching = Lists.newArrayList();
         for (RootInfo root : roots) {
             final boolean supportsCreate = (root.flags & Root.FLAG_SUPPORTS_CREATE) != 0;
+            final boolean supportsDir = (root.flags & Root.FLAG_SUPPORTS_DIR_SELECTION) != 0;
             final boolean advanced = (root.flags & Root.FLAG_ADVANCED) != 0;
             final boolean localOnly = (root.flags & Root.FLAG_LOCAL_ONLY) != 0;
             final boolean empty = (root.flags & Root.FLAG_EMPTY) != 0;
 
             // Exclude read-only devices when creating
             if (state.action == State.ACTION_CREATE && !supportsCreate) continue;
+            // Exclude roots that don't support directory picking
+            if (state.action == State.ACTION_PICK_DIRECTORY && !supportsDir) continue;
             // Exclude advanced devices when not requested
             if (!state.showAdvanced && advanced) continue;
             // Exclude non-local devices when local only
diff --git a/packages/DocumentsUI/src/com/android/documentsui/TestActivity.java b/packages/DocumentsUI/src/com/android/documentsui/TestActivity.java
deleted file mode 100644
index 1a47308..0000000
--- a/packages/DocumentsUI/src/com/android/documentsui/TestActivity.java
+++ /dev/null
@@ -1,268 +0,0 @@
-/*
- * Copyright (C) 2013 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.documentsui;
-
-import android.app.Activity;
-import android.content.Context;
-import android.content.Intent;
-import android.net.Uri;
-import android.os.Bundle;
-import android.provider.DocumentsContract;
-import android.util.Log;
-import android.view.View;
-import android.view.View.OnClickListener;
-import android.widget.Button;
-import android.widget.CheckBox;
-import android.widget.LinearLayout;
-import android.widget.ScrollView;
-import android.widget.TextView;
-
-import libcore.io.IoUtils;
-import libcore.io.Streams;
-
-import java.io.InputStream;
-import java.io.OutputStream;
-
-public class TestActivity extends Activity {
-    private static final String TAG = "TestActivity";
-
-    private static final int CODE_READ = 42;
-    private static final int CODE_WRITE = 43;
-
-    private TextView mResult;
-
-    @Override
-    public void onCreate(Bundle icicle) {
-        super.onCreate(icicle);
-
-        final Context context = this;
-
-        final LinearLayout view = new LinearLayout(context);
-        view.setOrientation(LinearLayout.VERTICAL);
-
-        mResult = new TextView(context);
-        view.addView(mResult);
-
-        final CheckBox multiple = new CheckBox(context);
-        multiple.setText("ALLOW_MULTIPLE");
-        view.addView(multiple);
-        final CheckBox localOnly = new CheckBox(context);
-        localOnly.setText("LOCAL_ONLY");
-        view.addView(localOnly);
-
-        Button button;
-        button = new Button(context);
-        button.setText("OPEN_DOC */*");
-        button.setOnClickListener(new OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
-                intent.addCategory(Intent.CATEGORY_OPENABLE);
-                intent.setType("*/*");
-                if (multiple.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
-                }
-                if (localOnly.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
-                }
-                startActivityForResult(intent, CODE_READ);
-            }
-        });
-        view.addView(button);
-
-        button = new Button(context);
-        button.setText("OPEN_DOC image/*");
-        button.setOnClickListener(new OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
-                intent.addCategory(Intent.CATEGORY_OPENABLE);
-                intent.setType("image/*");
-                if (multiple.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
-                }
-                if (localOnly.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
-                }
-                startActivityForResult(intent, CODE_READ);
-            }
-        });
-        view.addView(button);
-
-        button = new Button(context);
-        button.setText("OPEN_DOC audio/ogg");
-        button.setOnClickListener(new OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
-                intent.addCategory(Intent.CATEGORY_OPENABLE);
-                intent.setType("audio/ogg");
-                if (multiple.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
-                }
-                if (localOnly.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
-                }
-                startActivityForResult(intent, CODE_READ);
-            }
-        });
-        view.addView(button);
-
-        button = new Button(context);
-        button.setText("OPEN_DOC text/plain, application/msword");
-        button.setOnClickListener(new OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
-                intent.addCategory(Intent.CATEGORY_OPENABLE);
-                intent.setType("*/*");
-                intent.putExtra(Intent.EXTRA_MIME_TYPES, new String[] {
-                        "text/plain", "application/msword" });
-                if (multiple.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
-                }
-                if (localOnly.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
-                }
-                startActivityForResult(intent, CODE_READ);
-            }
-        });
-        view.addView(button);
-
-        button = new Button(context);
-        button.setText("CREATE_DOC text/plain");
-        button.setOnClickListener(new OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                Intent intent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
-                intent.addCategory(Intent.CATEGORY_OPENABLE);
-                intent.setType("text/plain");
-                intent.putExtra(Intent.EXTRA_TITLE, "foobar.txt");
-                if (localOnly.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
-                }
-                startActivityForResult(intent, CODE_WRITE);
-            }
-        });
-        view.addView(button);
-
-        button = new Button(context);
-        button.setText("CREATE_DOC image/png");
-        button.setOnClickListener(new OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                Intent intent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
-                intent.addCategory(Intent.CATEGORY_OPENABLE);
-                intent.setType("image/png");
-                intent.putExtra(Intent.EXTRA_TITLE, "mypicture.png");
-                if (localOnly.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
-                }
-                startActivityForResult(intent, CODE_WRITE);
-            }
-        });
-        view.addView(button);
-
-        button = new Button(context);
-        button.setText("GET_CONTENT */*");
-        button.setOnClickListener(new OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
-                intent.addCategory(Intent.CATEGORY_OPENABLE);
-                intent.setType("*/*");
-                if (multiple.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
-                }
-                if (localOnly.isChecked()) {
-                    intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
-                }
-                startActivityForResult(Intent.createChooser(intent, "Kittens!"), CODE_READ);
-            }
-        });
-        view.addView(button);
-
-        final ScrollView scroll = new ScrollView(context);
-        scroll.addView(view);
-
-        setContentView(scroll);
-    }
-
-    @Override
-    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
-        mResult.setText(null);
-        String result = "resultCode=" + resultCode + ", data=" + String.valueOf(data);
-
-        if (requestCode == CODE_READ) {
-            final Uri uri = data != null ? data.getData() : null;
-            if (uri != null) {
-                if (DocumentsContract.isDocumentUri(this, uri)) {
-                    result += "; DOC_ID";
-                }
-                try {
-                    getContentResolver().takePersistableUriPermission(
-                            uri, Intent.FLAG_GRANT_READ_URI_PERMISSION);
-                } catch (SecurityException e) {
-                    result += "; FAILED TO TAKE";
-                    Log.e(TAG, "Failed to take", e);
-                }
-                InputStream is = null;
-                try {
-                    is = getContentResolver().openInputStream(uri);
-                    final int length = Streams.readFullyNoClose(is).length;
-                    result += "; read length=" + length;
-                } catch (Exception e) {
-                    result += "; ERROR";
-                    Log.e(TAG, "Failed to read " + uri, e);
-                } finally {
-                    IoUtils.closeQuietly(is);
-                }
-            } else {
-                result += "no uri?";
-            }
-        } else if (requestCode == CODE_WRITE) {
-            final Uri uri = data != null ? data.getData() : null;
-            if (uri != null) {
-                if (DocumentsContract.isDocumentUri(this, uri)) {
-                    result += "; DOC_ID";
-                }
-                try {
-                    getContentResolver().takePersistableUriPermission(
-                            uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
-                } catch (SecurityException e) {
-                    result += "; FAILED TO TAKE";
-                    Log.e(TAG, "Failed to take", e);
-                }
-                OutputStream os = null;
-                try {
-                    os = getContentResolver().openOutputStream(uri);
-                    os.write("THE COMPLETE WORKS OF SHAKESPEARE".getBytes());
-                } catch (Exception e) {
-                    result += "; ERROR";
-                    Log.e(TAG, "Failed to write " + uri, e);
-                } finally {
-                    IoUtils.closeQuietly(os);
-                }
-            } else {
-                result += "no uri?";
-            }
-        }
-
-        Log.d(TAG, result);
-        mResult.setText(result);
-    }
-}
diff --git a/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java b/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java
index 559e052..16fc3e5 100644
--- a/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java
+++ b/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java
@@ -27,6 +27,7 @@ import android.net.Uri;
 import android.os.CancellationSignal;
 import android.os.Environment;
 import android.os.FileObserver;
+import android.os.FileUtils;
 import android.os.ParcelFileDescriptor;
 import android.os.storage.StorageManager;
 import android.os.storage.StorageVolume;
@@ -143,7 +144,7 @@ public class ExternalStorageProvider extends DocumentsProvider {
                 final RootInfo root = new RootInfo();
                 root.rootId = rootId;
                 root.flags = Root.FLAG_SUPPORTS_CREATE | Root.FLAG_LOCAL_ONLY | Root.FLAG_ADVANCED
-                        | Root.FLAG_SUPPORTS_SEARCH;
+                        | Root.FLAG_SUPPORTS_SEARCH | Root.FLAG_SUPPORTS_DIR_SELECTION;
                 if (ROOT_ID_PRIMARY_EMULATED.equals(rootId)) {
                     root.title = getContext().getString(R.string.root_internal_storage);
                 } else {
@@ -240,8 +241,8 @@ public class ExternalStorageProvider extends DocumentsProvider {
                 flags |= Document.FLAG_DIR_SUPPORTS_CREATE;
             } else {
                 flags |= Document.FLAG_SUPPORTS_WRITE;
+                flags |= Document.FLAG_SUPPORTS_DELETE;
             }
-            flags |= Document.FLAG_SUPPORTS_DELETE;
         }
 
         final String displayName = file.getName();
@@ -284,11 +285,26 @@ public class ExternalStorageProvider extends DocumentsProvider {
     }
 
     @Override
+    public boolean isChildDocument(String parentDocId, String docId) {
+        try {
+            final File parent = getFileForDocId(parentDocId).getCanonicalFile();
+            final File doc = getFileForDocId(docId).getCanonicalFile();
+            return FileUtils.contains(parent, doc);
+        } catch (IOException e) {
+            throw new IllegalArgumentException(
+                    "Failed to determine if " + docId + " is child of " + parentDocId + ": " + e);
+        }
+    }
+
+    @Override
     public String createDocument(String docId, String mimeType, String displayName)
             throws FileNotFoundException {
         final File parent = getFileForDocId(docId);
-        File file;
+        if (!parent.isDirectory()) {
+            throw new IllegalArgumentException("Parent document isn't a directory");
+        }
 
+        File file;
         if (Document.MIME_TYPE_DIR.equals(mimeType)) {
             file = new File(parent, displayName);
             if (!file.mkdir()) {
@@ -317,6 +333,7 @@ public class ExternalStorageProvider extends DocumentsProvider {
 
     @Override
     public void deleteDocument(String docId) throws FileNotFoundException {
+        // TODO: extend to delete directories
         final File file = getFileForDocId(docId);
         if (!file.delete()) {
             throw new IllegalStateException("Failed to delete " + file);