Question

真的很沮丧。这是我的代码：

public class FileIO {
    public static void writeString(FileOutputStream out, String target) throws IOException {
        target += "\n";
        for ( int i = 0; i < target.length(); i ++ ) {
            out.write(target.charAt(i));
        }
        out.flush();
    }


    public static void copy(File src, File dst) throws IOException {
        InputStream in = new FileInputStream(src);
        OutputStream out = new FileOutputStream(dst);

        // Transfer bytes from in to out
        byte[] buf = new byte[1024];
        int len;
        while ((len = in.read(buf)) > 0) {
            out.write(buf, 0, len);
        }
        in.close();
        out.close();
    }


    public static void createFile(String path) throws IOException {
        File f = new File(path);
        if ( !f.exists() )
            f.createNewFile();
    }
}

出于绝望，我把它添加到我的清单中：

<uses-permission android:name="android.permission.ACCESS_SUPERUSER" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
    <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS" />
    <uses-permission android:name="android.permission.BATTERY_STATS" />
    <uses-permission android:name="android.permission.BLUETOOTH" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <uses-permission android:name="android.permission.BROADCAST_STICKY" />
    <uses-permission android:name="android.permission.CALL_PHONE"/>
    <uses-permission android:name="android.permission.CHANGE_CONFIGURATION" />
    <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
    <uses-permission android:name="android.permission.CLEAR_APP_CACHE" />
    <uses-permission android:name="android.permission.DISABLE_KEYGUARD" />
    <uses-permission android:name="android.permission.EXPAND_STATUS_BAR" />
    <uses-permission android:name="android.permission.FLASHLIGHT" />
    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
    <uses-permission android:name="android.permission.GET_PACKAGE_SIZE" />
    <uses-permission android:name="android.permission.GET_TASKS" />
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES" />
    <uses-permission android:name="android.permission.MANAGE_ACCOUNTS" />
    <uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
    <uses-permission android:name="android.permission.MOUNT_FORMAT_FILESYSTEMS" />
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
    <uses-permission android:name="android.permission.NFC" />
    <uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS" />
    <uses-permission android:name="android.permission.READ_CALENDAR" />
    <uses-permission android:name="android.permission.READ_CONTACTS" />
    <uses-permission android:name="android.permission.READ_HISTORY_BOOKMARKS" />
    <uses-permission android:name="android.permission.READ_LOGS" />
    <uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.READ_SMS" />
    <uses-permission android:name="android.permission.READ_SYNC_SETTINGS" />
    <uses-permission android:name="android.permission.READ_SYNC_STATS" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
    <uses-permission android:name="android.permission.RECEIVE_MMS" />
    <uses-permission android:name="android.permission.RECEIVE_SMS" />
    <uses-permission android:name="android.permission.RECEIVE_WAP_PUSH" />
    <uses-permission android:name="android.permission.RECORD_AUDIO" />
    <uses-permission android:name="android.permission.REORDER_TASKS" />
    <uses-permission android:name="android.permission.RESTART_PACKAGES" />
    <uses-permission android:name="android.permission.SEND_SMS" />
    <uses-permission android:name="android.permission.SET_ALARM" />
    <uses-permission android:name="android.permission.SET_ALWAYS_FINISH" />
    <uses-permission android:name="android.permission.SET_ANIMATION_SCALE" />
    <uses-permission android:name="android.permission.SET_DEBUG_APP" />
    <uses-permission android:name="android.permission.SET_PROCESS_LIMIT" />
    <uses-permission android:name="android.permission.SET_TIME_ZONE" />
    <uses-permission android:name="android.permission.SET_WALLPAPER" />
    <uses-permission android:name="android.permission.SET_WALLPAPER_HINTS" />
    <uses-permission android:name="android.permission.SIGNAL_PERSISTENT_PROCESSES" />
    <uses-permission android:name="android.permission.SUBSCRIBED_FEEDS_READ" />
    <uses-permission android:name="android.permission.SUBSCRIBED_FEEDS_WRITE" />
    <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
    <uses-permission android:name="android.permission.USE_CREDENTIALS" />
    <uses-permission android:name="android.permission.USE_SIP" />
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.WRITE_CALENDAR" />
    <uses-permission android:name="android.permission.WRITE_CONTACTS" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_HISTORY_BOOKMARKS" />
    <uses-permission android:name="android.permission.WRITE_SETTINGS" />
    <uses-permission android:name="android.permission.WRITE_SMS" />
    <uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS" />

    <uses-permission android:name="android.permission.BIND_ACCESSIBILITY_SERVICE"/>
    <uses-permission android:name="android.permission.PERSISTENT_ACTIVITY"/>
    <uses-permission android:name="android.permission.READ_CALL_LOG"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <uses-permission android:name="com.android.browser.permission.READ_HISTORY_BOOKMARKS"/>
    <uses-permission android:name="android.permission.READ_PROFILE"/>
    <uses-permission android:name="android.permission.READ_SOCIAL_STREAM"/>
    <uses-permission android:name="android.permission.READ_USER_DICTIONARY"/>
    <uses-permission android:name="com.android.alarm.permission.SET_ALARM"/>
    <uses-permission android:name="android.permission.WRITE_CALL_LOG"/>
    <uses-permission android:name="com.android.browser.permission.WRITE_HISTORY_BOOKMARKS"/>
    <uses-permission android:name="android.permission.WRITE_PROFILE"/>
    <uses-permission android:name="android.permission.WRITE_SOCIAL_STREAM"/>
    <uses-permission android:name="android.permission.WRITE_USER_DICTIONARY"/>

并且此代码表示我具有写入所需的权限：

String permission = "android.permission.WRITE_EXTERNAL_STORAGE";
        int res = c.checkCallingOrSelfPermission(permission);
        Debug.log("WRITE_EXTERNAL_STORAGE: " + (res == PackageManager.PERMISSION_GRANTED));

但是，我知道了：

06-23 20:50:35.709: W/System.err(5722): java.io.FileNotFoundException: /mnt/sdcard/package.zip (Permission denied)

它不仅在这个文件上，我只是不能在SD卡上读/写任何东西，如果这还不够，我无法访问互联网，我使用GMailSender并记录下来：

06-23 20：50：35.809：I / Adnan（5722）：javax.mail.MessagingException：无法连接到SMTP主机：smtp.gmail.com，port：465; 06-23 20：50：35.809：I / Adnan（5722）：嵌套异常是：06-23 20：50：35.809：I / Adnan（5722）：java.net.SocketException：Permission 拒绝

但正如您在权限墙上看到的那样，我也添加了INTERNET。任何人都可以告诉我这里发生了什么？

Answer 1

此错误与Android权限无关。这是文件系统权限错误。这意味着您没有SD卡中此文件夹的写入权限。

通常在启用USB存储器时发生。当您的设备未连接到计算机时，请尝试运行您的代码。

Answer 2

在我访问sdcard的应用程序中，/ mnt不在路径中。尝试删除它。

此外，了解您是使用真实设备还是模拟器进行测试会很有帮助。

无法在android上写文件

2 个答案: