Android的性能一旦圖片選擇是可怕的

Question

我有一個圖像採集方法，它可以讓用戶從他們的畫廊選擇一個圖像。

一旦圖像被選中，應用程序變得非常可怕，頁面上有3個文本框，當你點擊它們需要大約3秒鐘時間纔會出現鍵盤，並且它出現在laggy階段。

logcat的警告：

12-03 19:03:35.536 10842-10842/.com. I/Choreographer﹕ Skipped 58 frames! The 
    application may be doing too much work on its main thread. 

所以，我試圖把圖片選擇一個新的線程，但有太多的方法來單獨封裝。

對於這樣一個簡單的任務，低性能的常見問題/解決方案是什麼？

代碼：

@Override 
    public void onCreate(Bundle savedInstanceState) { 

     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_submit); 

     imageView = (ImageView) findViewById(R.id.submitImageButton); 
     button = (ImageView) findViewById(R.id.submitImageButton); 

    } 

    public void pickPhoto(View view) { 

     new Thread(new Runnable() { 
      public void run() { 

       // launch the photo picker 
       Intent intent = new Intent(); 
       intent.setType("image/*"); 
       intent.setAction(Intent.ACTION_GET_CONTENT); 
       startActivityForResult(Intent.createChooser(intent, 
         "Select Picture"), SELECT_PICTURE); 
      } 
     }).start(); 

    } 

    protected void onActivityResult(int requestCode, int resultCode, Intent data) { 
     super.onActivityResult(requestCode, resultCode, data); 
     if(resultCode == RESULT_OK) { 
      try { 
       Bitmap bitmap = getPath(data.getData()); 
       Log.i("Bitmap", "Bmp: " + data.getData()); 
       imageView.setImageBitmap(bitmap); 
      }catch (Exception e){ 
       Log.e("Error", "Error with setting the image. See stack trace."); 
       e.printStackTrace(); 
      } 
     } 
    } 

    private Bitmap getPath(Uri uri) { 


     button.setEnabled(false); 

     String[] projection = { MediaStore.Images.Media.DATA }; 
     Cursor cursor = getContentResolver().query(uri, projection, null, null, null); 

     cursor.moveToFirst(); 
     String filePath = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA)); 
     cursor.close(); 
     // Convert file path into bitmap image using below line. 



     Bitmap bitmap = BitmapFactory.decodeFile(filePath); 

     filePathForUpload = filePath; 

     try { 
      ExifInterface exif = new ExifInterface(filePath); 
      int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_UNDEFINED); 
      bitmap = rotateBitmap(bitmap, orientation); 
     }catch (Exception e){ 
      Log.d("Error", "error with bitmap!"); 
      e.printStackTrace(); 
     } 

     return bitmap; 
    } 


    public static Bitmap rotateBitmap(Bitmap bitmap, int orientation) { 
     Matrix matrix = new Matrix(); 
     switch (orientation) { 
      case ExifInterface.ORIENTATION_NORMAL: 
       return bitmap; 
      case ExifInterface.ORIENTATION_FLIP_HORIZONTAL: 
       matrix.setScale(-1, 1); 
       break; 
      case ExifInterface.ORIENTATION_ROTATE_180: 
       matrix.setRotate(180); 
       break; 
      case ExifInterface.ORIENTATION_FLIP_VERTICAL: 
       matrix.setRotate(180); 
       matrix.postScale(-1, 1); 
       break; 
      case ExifInterface.ORIENTATION_TRANSPOSE: 
       matrix.setRotate(90); 
       matrix.postScale(-1, 1); 
       break; 
      case ExifInterface.ORIENTATION_ROTATE_90: 
       matrix.setRotate(90); 
       break; 
      case ExifInterface.ORIENTATION_TRANSVERSE: 
       matrix.setRotate(-90); 
       matrix.postScale(-1, 1); 
       break; 
      case ExifInterface.ORIENTATION_ROTATE_270: 
       matrix.setRotate(-90); 
       break; 
      default: 
       return bitmap; 
     } 

     Bitmap bmRotated = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true); 
     bitmap.recycle(); 
     return bmRotated; 
    } 

Answer 1

你應該把你的位圖創建一個單獨的線程（即的getPath（...）和rotateBitmap（...），而不是你的意圖挑照片（pickPhoto（查看視圖）。

而不是通過創建一個新的位圖來旋轉你的位圖，爲什麼不只是在一個ImageView上設置位圖並使用View.setRotation（float x）？這樣，你不會創建一個每當你旋轉圖像時新的位圖