如何在imageview android中顯示大尺寸的位圖？

Question

我的圖像高度超過6000像素。每當我嘗試顯示這些圖像時，都會發現內存異常。

我看過很多鏈接，但沒有符合我的需求。因爲大多數人建議圖像調整解決方案。但是，如果我將重新調整圖像的尺寸，而不是由於質量較差而無法讀取圖像中的文字。

我想在創建一些代碼時可以打開一個圖像，而無需通過縮放效果重新調整大小。

任何幫助將非常感激。

Answer 1

嘗試使用的WebView來顯示圖像，而不是ImageView的

的

Answer 2

我建議你在3個較小的圖像中「剪切」這個圖像，然後將它們作爲三個圖像加載：第一個圖像位於y：0，高度爲2000px，第二個圖像的長度爲2000px，高度爲2000px，第三個在y：4000px。 你認爲這可行嗎？ 好運

Answer 3

嘗試使用google推薦了這個問題。

爲了避免OOM您需要執行的代碼塊：

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; 
} 

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; 
} 

Answer 4

試試這個：

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_fullscreen_view); 

    imageView = (ImageView) findViewById(R.id.full_image_view); 
    imageView.setImageBitmap(decodeSampledBitmapFromResource(imgpath)); 
} 


    //Load a bitmap from a resource with a target size 
Bitmap decodeSampledBitmapFromResource(String res) { 
    // First decode with inJustDecodeBounds=true to check dimensions 
    final BitmapFactory.Options options = new BitmapFactory.Options(); 
    options.inJustDecodeBounds = true; 
    BitmapFactory.decodeFile(res, options); 

    //Calculate display dimention for maximum reqwidth and reqheigth 
    Display display = getWindowManager().getDefaultDisplay(); 
    Point size = new Point(); 
    display.getSize(size); 
    int xDim = size.x; 
    int yDim = size.y; 


    // Calculate inSampleSize 
    options.inSampleSize = calculateInSampleSize(options, xDim, yDim); 
    // Decode bitmap with inSampleSize se5t 
    options.inJustDecodeBounds = false; 
    return BitmapFactory.decodeFile(res, options); 
} 


int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) { 
    int inSampleSize = 1; //Default subsampling size 
    // Calculate the largest inSampleSize value 
    while ((options.outHeight/inSampleSize) > reqHeight 
      || (options.outWidth/inSampleSize) > reqWidth) { 
     inSampleSize += 1; 
    } 
    return inSampleSize; 
} 

Answer 5

在應用程序清單文件標記設置largeHeap真

<application 
     android:largeHeap="true" 

而且使用Picasso或Glide在ImageView中加載圖像