MY_PERMISSONS_REQUEST未定義？

Question

我正在嘗試檢查應用程序的權限，並且當前正在進行Android開發人員培訓。 但是，在插入page中列出的代碼時遇到了問題。

該頁面聲稱MY_PERMISSIONS_REQUEST是一個應用程序定義的int常量。然而，當我把它放在我的實際應用程序中時，它說它沒有被定義...

有人可以解釋爲什麼會出現這種情況嗎？ 謝謝！

示例代碼：

// Here, thisActivity is the current activity 
if (ContextCompat.checkSelfPermission(thisActivity, 
       Manifest.permission.READ_CONTACTS) 
     != PackageManager.PERMISSION_GRANTED) { 

    // Should we show an explanation? 
    if (ActivityCompat.shouldShowRequestPermissionRationale(thisActivity, 
      Manifest.permission.READ_CONTACTS)) { 

     // Show an expanation to the user *asynchronously* -- don't block 
     // this thread waiting for the user's response! After the user 
     // sees the explanation, try again to request the permission. 

    } else { 

     // No explanation needed, we can request the permission. 

     ActivityCompat.requestPermissions(thisActivity, 
       new String[]{Manifest.permission.READ_CONTACTS}, 
       MY_PERMISSIONS_REQUEST_READ_CONTACTS); 

     // MY_PERMISSIONS_REQUEST_READ_CONTACTS is an 
     // app-defined int constant. The callback method gets the 
     // result of the request. 
    } 
} 

Answer 1

你可能只是把它定義爲一個場不變，就像這樣：

private static final int MY_PERMISSIONS_REQUEST_READ_CONTACTS = 1; 

// Here, thisActivity is the current activity 
if (ContextCompat.checkSelfPermission(thisActivity, 
       Manifest.permission.READ_CONTACTS) 
     != PackageManager.PERMISSION_GRANTED) { 
    ... 

這是因爲可能有其他請求。您可以通過您定義的請求代碼與其他人區分。