从图库中获取资源ID

在尝试从BitmapFactory中找到解决内存不足错误的解决方案后，发现本教程。 http://developer.android.com/training/displaying-bitmaps/load-bitmap.html 从图库中获取资源ID

我明白所有的它除了线 mImageView.setImageBitmap（ decodeSampledBitmapFromResource（getResources（），R.id.myimage，100，100））;

第二个参数要求图像的资源ID，我不确定它来自哪里。这是我的代码如下所示：

Button buttonLoadImage = (Button) findViewById(R.id.buttonLoadImage); 
    buttonLoadImage.setOnClickListener(new View.OnClickListener() { 

     @Override 
     public void onClick(View arg0) { 

      Intent i = new Intent(
        Intent.ACTION_PICK, 
        android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI); 

      startActivityForResult(i, RESULT_LOAD_IMAGE); 
     } 
    }); 
} 


@Override 
protected void onActivityResult(int requestCode, int resultCode, Intent data) { 
    super.onActivityResult(requestCode, resultCode, data); 

    if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) { 
     Uri selectedImage = data.getData(); 
     String[] filePathColumn = { MediaStore.Images.Media.DATA }; 

     Cursor cursor = getContentResolver().query(selectedImage, 
       filePathColumn, null, null, null); 
     cursor.moveToFirst(); 

     int columnIndex = cursor.getColumnIndex(filePathColumn[0]); 
     String picturePath = cursor.getString(columnIndex); 


     //http://developer.android.com/training/displaying-bitmaps/load-bitmap.html 
     BitmapFactory.Options options = new BitmapFactory.Options(); 
     options.inJustDecodeBounds = true; 
     BitmapFactory.decodeResource(getResources(), R.id.imgView, options); 
     int imageHeight = options.outHeight; 
     int imageWidth = options.outWidth; 
     String imageType = options.outMimeType; 

     ImageView imageView = (ImageView) findViewById(R.id.imgView); 
     //imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath)); 
     imageView.setImageBitmap(
       decodeSampledBitmapFromResource(getResources(),res, imageView.getWidth(), imageView.getHeight())); 
     cursor.close(); 
    } 

} 
public static int calculateInSampleSize(
     BitmapFactory.Options options, int reqWidth, int reqHeight) { 
// Raw height and width of image 
final int height = options.outHeight; 
final int width = options.outWidth; 
int inSampleSize = 1; 

if (height > reqHeight || width > reqWidth) { 

    final int halfHeight = height/2; 
    final int halfWidth = width/2; 

    // Calculate the largest inSampleSize value that is a power of 2 and keeps both 
    // height and width larger than the requested height and width. 
    while ((halfHeight/inSampleSize) > reqHeight 
      && (halfWidth/inSampleSize) > reqWidth) { 
     inSampleSize *= 2; 
    } 
} 

return inSampleSize;

} 公共静态位图decodeSampledBitmapFromResource（资源RES，INT渣油， INT reqWidth，诠释reqHeight）{

// First decode with inJustDecodeBounds=true to check dimensions 
    final BitmapFactory.Options options = new BitmapFactory.Options(); 
    options.inJustDecodeBounds = true; 
    BitmapFactory.decodeResource(res, resId, options); 

    // Calculate inSampleSize 
    options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight); 

    // Decode bitmap with inSampleSize set 
    options.inJustDecodeBounds = false; 
    return BitmapFactory.decodeResource(res, resId, options); 
}

来源

2014-05-06 Naughtlok

资源ID引用位图你的应用程序的res/drawable文件夹。如果图像位于其他位置（如图库），则必须找到其他方法来加载图像并获取位图。看看方法，BitmapFactory规定。

来源

2014-05-06 06:45:50 Ridcully

我原本使用的是\t \t \t imageView.setImageBitmap（BitmapFactory.decodeFile（picturePath））; 它在较小的图像上工作得很好。对于任何大型图像，我都会遇到内存不足的情况。有没有办法将picturePath转换为字符串？ – Naughtlok

你为什么要改变一个刺痛的路径？无论如何你必须阅读图片文件。尝试使用'BitmapFactory.decodeFile（picturePath，options）'，对于这些选项，在您的问题的'decodeSampledBitmapFromResource（）'方法中使用带有'options.inSampleSize'的位。这样，你会得到一个不应该打动你的记忆的小图片。 – Ridcully

从图库中获取资源ID

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