安卓相機功能getcameraIdlist（）函數不返回任何東西

Question

1. 代碼生成IllegalArguementException。
2. 儘管manifest中給出了所有permissions，但該列表似乎並未填充。

3. 應用程序崩潰只要Activity打開。

   公共類照片延伸活動{0}私人處理程序mhandler; public CameraDevice cam; private CameraDevice.StateCallback mcallback;

   public void setCallback(CameraDevice.StateCallback callback) { 
       this.mcallback = callback; 
   } 
   
   public void setHandler(Handler handler) { 
       this.mhandler = handler; 
   } 
   
   
   int count=0; 
   @Override 
   protected void onCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState); 
       setContentView(R.layout.main_photo); 
   
       String[] list=new String[10]; 
       CameraManager camera = (CameraManager) getSystemService(Context.CAMERA_SERVICE); 
   
       setCallback(mcallback); 
       setHandler(mhandler); 
       ListView cami = (ListView) findViewById(R.id.lv); 
   
       ArrayAdapter adapter = new ArrayAdapter<String>(this, R.layout.main_photo, R.id.textView2, list); 
   
       cami.setAdapter(adapter); 
   
       try 
   
       { 
        list = camera.getCameraIdList(); 
        count++; 
   
       } catch (CameraAccessException e) 
   
       { 
        e.printStackTrace(); 
       } 
   
   
   
   
        try 
   
        { 
         camera.openCamera(list[0], mcallback, mhandler); 
         mcallback.onOpened(cam); 
   
   
        } catch (CameraAccessException e) 
   
        { 
         e.printStackTrace(); 
   
         Log.d("Photo", "Error in opening camera"); 
        } catch (IllegalArgumentException a) 
   
        { 
         Log.d("Callback", "Callback Problem"); 
        } 
   
       } 
   

Answer 1

除非我失去了一些東西，儘可能我可以告訴mhandler和mcallback在你調用setCallback(mcallback)和setHandler(mhandler)兩空。嘗試在致電camera.openCamera(list[0], mcallback, mhandler)之前驗證這兩個變量。

作爲附註，數組String[] list=new String[10]從不使用，您的變量將在7行後重新分配。也許相反，使用String[] list;然後7行後，使用list = camera.getCameraIdList();或簡單地String[] list=camera.getCameraIdList();