| /* |
| * Copyright (C) 2012 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 android.support.v4.content; |
| |
| import android.content.Context; |
| import android.content.Intent; |
| import android.os.Build; |
| import android.os.Bundle; |
| import android.os.Environment; |
| import android.os.StatFs; |
| import android.support.v4.os.EnvironmentCompat; |
| |
| import java.io.File; |
| |
| /** |
| * Helper for accessing features in {@link android.content.Context} |
| * introduced after API level 4 in a backwards compatible fashion. |
| */ |
| public class ContextCompat { |
| |
| private static final String DIR_ANDROID = "Android"; |
| private static final String DIR_DATA = "data"; |
| private static final String DIR_OBB = "obb"; |
| private static final String DIR_FILES = "files"; |
| private static final String DIR_CACHE = "cache"; |
| |
| /** |
| * Start a set of activities as a synthesized task stack, if able. |
| * |
| * <p>In API level 11 (Android 3.0/Honeycomb) the recommended conventions for |
| * app navigation using the back key changed. The back key's behavior is local |
| * to the current task and does not capture navigation across different tasks. |
| * Navigating across tasks and easily reaching the previous task is accomplished |
| * through the "recents" UI, accessible through the software-provided Recents key |
| * on the navigation or system bar. On devices with the older hardware button configuration |
| * the recents UI can be accessed with a long press on the Home key.</p> |
| * |
| * <p>When crossing from one task stack to another post-Android 3.0, |
| * the application should synthesize a back stack/history for the new task so that |
| * the user may navigate out of the new task and back to the Launcher by repeated |
| * presses of the back key. Back key presses should not navigate across task stacks.</p> |
| * |
| * <p>startActivities provides a mechanism for constructing a synthetic task stack of |
| * multiple activities. If the underlying API is not available on the system this method |
| * will return false.</p> |
| * |
| * @param context Start activities using this activity as the starting context |
| * @param intents Array of intents defining the activities that will be started. The element |
| * length-1 will correspond to the top activity on the resulting task stack. |
| * @return true if the underlying API was available and the call was successful, false otherwise |
| */ |
| public static boolean startActivities(Context context, Intent[] intents) { |
| return startActivities(context, intents, null); |
| } |
| |
| /** |
| * Start a set of activities as a synthesized task stack, if able. |
| * |
| * <p>In API level 11 (Android 3.0/Honeycomb) the recommended conventions for |
| * app navigation using the back key changed. The back key's behavior is local |
| * to the current task and does not capture navigation across different tasks. |
| * Navigating across tasks and easily reaching the previous task is accomplished |
| * through the "recents" UI, accessible through the software-provided Recents key |
| * on the navigation or system bar. On devices with the older hardware button configuration |
| * the recents UI can be accessed with a long press on the Home key.</p> |
| * |
| * <p>When crossing from one task stack to another post-Android 3.0, |
| * the application should synthesize a back stack/history for the new task so that |
| * the user may navigate out of the new task and back to the Launcher by repeated |
| * presses of the back key. Back key presses should not navigate across task stacks.</p> |
| * |
| * <p>startActivities provides a mechanism for constructing a synthetic task stack of |
| * multiple activities. If the underlying API is not available on the system this method |
| * will return false.</p> |
| * |
| * @param context Start activities using this activity as the starting context |
| * @param intents Array of intents defining the activities that will be started. The element |
| * length-1 will correspond to the top activity on the resulting task stack. |
| * @param options Additional options for how the Activity should be started. |
| * See {@link android.content.Context#startActivity(Intent, Bundle) |
| * @return true if the underlying API was available and the call was successful, false otherwise |
| */ |
| public static boolean startActivities(Context context, Intent[] intents, |
| Bundle options) { |
| final int version = Build.VERSION.SDK_INT; |
| if (version >= 16) { |
| ContextCompatJellybean.startActivities(context, intents, options); |
| return true; |
| } else if (version >= 11) { |
| ContextCompatHoneycomb.startActivities(context, intents); |
| return true; |
| } |
| return false; |
| } |
| |
| /** |
| * Returns absolute paths to application-specific directories on all |
| * external storage devices where the application's OBB files (if there are |
| * any) can be found. Note if the application does not have any OBB files, |
| * these directories may not exist. |
| * <p> |
| * This is like {@link Context#getFilesDir()} in that these files will be |
| * deleted when the application is uninstalled, however there are some |
| * important differences: |
| * <ul> |
| * <li>External files are not always available: they will disappear if the |
| * user mounts the external storage on a computer or removes it. |
| * <li>There is no security enforced with these files. |
| * </ul> |
| * <p> |
| * External storage devices returned here are considered a permanent part of |
| * the device, including both emulated external storage and physical media |
| * slots, such as SD cards in a battery compartment. The returned paths do |
| * not include transient devices, such as USB flash drives. |
| * <p> |
| * An application may store data on any or all of the returned devices. For |
| * example, an app may choose to store large files on the device with the |
| * most available space, as measured by {@link StatFs}. |
| * <p> |
| * Starting in {@link android.os.Build.VERSION_CODES#KITKAT}, no permissions |
| * are required to write to the returned paths; they're always accessible to |
| * the calling app. Before then, |
| * {@link android.Manifest.permission#WRITE_EXTERNAL_STORAGE} is required to |
| * write. Write access outside of these paths on secondary external storage |
| * devices is not available. To request external storage access in a |
| * backwards compatible way, consider using {@code android:maxSdkVersion} |
| * like this: |
| * |
| * <pre class="prettyprint"><uses-permission |
| * android:name="android.permission.WRITE_EXTERNAL_STORAGE" |
| * android:maxSdkVersion="18" /></pre> |
| * <p> |
| * The first path returned is the same as {@link Context#getObbDir()}. |
| * Returned paths may be {@code null} if a storage device is unavailable. |
| * |
| * @see Context#getObbDir() |
| * @see EnvironmentCompat#getStorageState(File) |
| */ |
| public static File[] getObbDirs(Context context) { |
| final int version = Build.VERSION.SDK_INT; |
| if (version >= 19) { |
| return ContextCompatKitKat.getObbDirs(context); |
| } else { |
| final File single; |
| if (version >= 11) { |
| single = ContextCompatHoneycomb.getObbDir(context); |
| } else { |
| single = buildPath(Environment.getExternalStorageDirectory(), DIR_ANDROID, DIR_OBB, |
| context.getPackageName()); |
| } |
| return new File[] { single }; |
| } |
| } |
| |
| /** |
| * Returns absolute paths to application-specific directories on all |
| * external storage devices where the application can place persistent files |
| * it owns. These files are internal to the application, and not typically |
| * visible to the user as media. |
| * <p> |
| * This is like {@link Context#getFilesDir()} in that these files will be |
| * deleted when the application is uninstalled, however there are some |
| * important differences: |
| * <ul> |
| * <li>External files are not always available: they will disappear if the |
| * user mounts the external storage on a computer or removes it. |
| * <li>There is no security enforced with these files. |
| * </ul> |
| * <p> |
| * External storage devices returned here are considered a permanent part of |
| * the device, including both emulated external storage and physical media |
| * slots, such as SD cards in a battery compartment. The returned paths do |
| * not include transient devices, such as USB flash drives. |
| * <p> |
| * An application may store data on any or all of the returned devices. For |
| * example, an app may choose to store large files on the device with the |
| * most available space, as measured by {@link StatFs}. |
| * <p> |
| * Starting in {@link android.os.Build.VERSION_CODES#KITKAT}, no permissions |
| * are required to write to the returned paths; they're always accessible to |
| * the calling app. Before then, |
| * {@link android.Manifest.permission#WRITE_EXTERNAL_STORAGE} is required to |
| * write. Write access outside of these paths on secondary external storage |
| * devices is not available. To request external storage access in a |
| * backwards compatible way, consider using {@code android:maxSdkVersion} |
| * like this: |
| * |
| * <pre class="prettyprint"><uses-permission |
| * android:name="android.permission.WRITE_EXTERNAL_STORAGE" |
| * android:maxSdkVersion="18" /></pre> |
| * <p> |
| * The first path returned is the same as |
| * {@link Context#getExternalFilesDir(String)}. Returned paths may be |
| * {@code null} if a storage device is unavailable. |
| * |
| * @see Context#getExternalFilesDir(String) |
| * @see EnvironmentCompat#getStorageState(File) |
| */ |
| public static File[] getExternalFilesDirs(Context context, String type) { |
| final int version = Build.VERSION.SDK_INT; |
| if (version >= 19) { |
| return ContextCompatKitKat.getExternalFilesDirs(context, type); |
| } else { |
| final File single; |
| if (version >= 8) { |
| single = ContextCompatFroyo.getExternalFilesDir(context, type); |
| } else { |
| single = buildPath(Environment.getExternalStorageDirectory(), DIR_ANDROID, DIR_DATA, |
| context.getPackageName(), DIR_FILES, type); |
| } |
| return new File[] { single }; |
| } |
| } |
| |
| /** |
| * Returns absolute paths to application-specific directories on all |
| * external storage devices where the application can place cache files it |
| * owns. These files are internal to the application, and not typically |
| * visible to the user as media. |
| * <p> |
| * This is like {@link Context#getCacheDir()} in that these files will be |
| * deleted when the application is uninstalled, however there are some |
| * important differences: |
| * <ul> |
| * <li>External files are not always available: they will disappear if the |
| * user mounts the external storage on a computer or removes it. |
| * <li>There is no security enforced with these files. |
| * </ul> |
| * <p> |
| * External storage devices returned here are considered a permanent part of |
| * the device, including both emulated external storage and physical media |
| * slots, such as SD cards in a battery compartment. The returned paths do |
| * not include transient devices, such as USB flash drives. |
| * <p> |
| * An application may store data on any or all of the returned devices. For |
| * example, an app may choose to store large files on the device with the |
| * most available space, as measured by {@link StatFs}. |
| * <p> |
| * Starting in {@link android.os.Build.VERSION_CODES#KITKAT}, no permissions |
| * are required to write to the returned paths; they're always accessible to |
| * the calling app. Before then, |
| * {@link android.Manifest.permission#WRITE_EXTERNAL_STORAGE} is required to |
| * write. Write access outside of these paths on secondary external storage |
| * devices is not available. To request external storage access in a |
| * backwards compatible way, consider using {@code android:maxSdkVersion} |
| * like this: |
| * |
| * <pre class="prettyprint"><uses-permission |
| * android:name="android.permission.WRITE_EXTERNAL_STORAGE" |
| * android:maxSdkVersion="18" /></pre> |
| * <p> |
| * The first path returned is the same as |
| * {@link Context#getExternalCacheDir()}. Returned paths may be {@code null} |
| * if a storage device is unavailable. |
| * |
| * @see Context#getExternalCacheDir() |
| * @see EnvironmentCompat#getStorageState(File) |
| */ |
| public static File[] getExternalCacheDirs(Context context) { |
| final int version = Build.VERSION.SDK_INT; |
| if (version >= 19) { |
| return ContextCompatKitKat.getExternalCacheDirs(context); |
| } else { |
| final File single; |
| if (version >= 8) { |
| single = ContextCompatFroyo.getExternalCacheDir(context); |
| } else { |
| single = buildPath(Environment.getExternalStorageDirectory(), DIR_ANDROID, DIR_DATA, |
| context.getPackageName(), DIR_CACHE); |
| } |
| return new File[] { single }; |
| } |
| } |
| |
| private static File buildPath(File base, String... segments) { |
| File cur = base; |
| for (String segment : segments) { |
| if (cur == null) { |
| cur = new File(segment); |
| } else if (segment != null) { |
| cur = new File(cur, segment); |
| } |
| } |
| return cur; |
| } |
| } |
