如何让文件存储在内置的外部存储

Question

我已经在SD卡上创建了一个名为MyDataBase的目录下的mdatabase.db文件，这很好，当我通过手机打开SD卡时，目录和文件正在显示，但是当我将设备连接到系统并通过系统打开创建的文件未显示。 请帮助我

这个问题只在抵达内置SD卡的设备，我

DataBasepath MNT/SD卡/ MYDATABASE/mdatabase.db

Answer 1

使用此代码检查介质的可用性

boolean mExternalStorageAvailable = false; 
boolean mExternalStorageWriteable = false; 
String state = Environment.getExternalStorageState(); 

if (Environment.MEDIA_MOUNTED.equals(state)) { 
    // We can read and write the media 
    mExternalStorageAvailable = mExternalStorageWriteable = true; 
} else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) { 
    // We can only read the media 
    mExternalStorageAvailable = true; 
    mExternalStorageWriteable = false; 
} else { 
    // Something else is wrong. It may be one of many other states, but all we need 
    // to know is we can neither read nor write 
    mExternalStorageAvailable = mExternalStorageWriteable = false; 
} 

请问您的代码取决于您的代码

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