无法在 Android 7.0 中创建文件夹

Posted 2023-04-14

【中文标题】无法在 Android 7.0 中创建文件夹

【英文标题】：Can't create folder in Android 7.0

【发布时间】：2017-12-10 04:54:19

【问题描述】：

我使用此代码创建文件夹。

 File folder2 = new File(Environment.getExternalStorageDirectory() + "/android");
        if (!folder2.exists()) 
            folder2.mkdir();
        


 File folder = new File(Environment.getExternalStorageDirectory() + "/Android/MyFolder");
        boolean success = true;
        if (!folder.exists()) 
            success = folder.mkdir();
        

它适用于其他设备，但不适用于 android v7.0。

我更改并尝试了 .getAbsolutePath() 和 .getPath()，但这些更改在其他设备上也成功，7.0 仍然没有。

而且清单上有足够的权限

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

请帮助我。感谢您的阅读。

【问题讨论】：

Manifest 权限不算什么，从 6.0+ 开始需要运行时权限才能写入

@EpicPandaForce，谢谢。我现在找到了。

查看此链接：***.com/questions/34342816/… 和 ***.com/a/36937109/1770868

【参考方案1】：

public static final int MULTIPLE_PERMISSIONS = 10; // code you want.

 String[] permissions= new String[]
        Manifest.permission.WRITE_EXTERNAL_STORAGE,
        Manifest.permission.WRITE_EXTERNAL_STORAGE
        ;


if (checkPermissions())
         //  permissions  granted.    
          createFolder();


private  boolean checkPermissions() 
        int result;
        List<String> listPermissionsNeeded = new ArrayList<>();
        for (String p:permissions) 
            result = ContextCompat.checkSelfPermission(getActivity(),p);
            if (result != PackageManager.PERMISSION_GRANTED) 
                listPermissionsNeeded.add(p);
            
        
        if (!listPermissionsNeeded.isEmpty()) 
            ActivityCompat.requestPermissions(this, listPermissionsNeeded.toArray(new String[listPermissionsNeeded.size()]),MULTIPLE_PERMISSIONS );
            return false;
        
        return true;
    


@Override
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) 
    switch (requestCode) 
        case MULTIPLE_PERMISSIONS:
            if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED)
                // permissions granted.
                createFolder();

             else 
                String permissions = "";
                for (String per : permissionsList) 
                    permissions += "\n" + per;
                
                // permissions list of don't granted permission
            
            return;
        
    


private void createFolder()

File folder2 = new File(Environment.getExternalStorageDirectory() + "/Android");
        if (!folder2.exists()) 
            folder2.mkdir();
        


 File folder = new File(Environment.getExternalStorageDirectory() + "/Android/MyFolder");
        boolean success = true;
        if (!folder.exists()) 
            success = folder.mkdir();
        

【讨论】：

谢谢。对于我的问题来说已经足够了。 (Y)

【参考方案2】：

如果您在 Android 6.0 或更高版本上运行您的应用。您需要询问run time permission 在您的活动文件中添加此请求权限代码

 String permission = Manifest.permission.WRITE_EXTERNAL_STORAGE;
            if (ActivityCompat.checkSelfPermission(MainActivity.this, permission)
                    != PackageManager.PERMISSION_GRANTED
                    ) 
                ActivityCompat.requestPermissions(MainActivity.this, new String[]
                        permission,123);