Android Studio Java-DecodeSampledBitmapFromResource不起作用

Question

我是Android Studio的新手，我正在尝试制作一个包含大量图像的应用程序，当然我收到了“ OutOfMemory”错误。 我已经搜索了解决方案，并在此主题中找到了一种建议的方法来解决它https://developer.android.com/topic/performance/graphics/load-bitmap.html

我完成了相同的方法，但是在调用了decodeSampledBitmapFromResource之后，图像没有出现

这是我的代码的一部分

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    image = (ImageView) findViewById(R.id.step2pointaprob4exc2img);

    image.setImageBitmap(ImageNiver.decodeSampledBitmapFromResource(getResources(),R.id.step2pointaprob4exc2img,reqwidth1,reqheight1));

    Display display = getWindowManager().getDefaultDisplay();
    Point size = new Point();
    display.getSize(size);
    int reqwidth1 = size.x;
    int reqheight1 = size.y;


    String s = String.valueOf(reqwidth1);
    String ss = String.valueOf(reqheight1);
    Log.i("value of s :",s);
    Log.i("value of ss :",ss);

这是我在imageNiver类上使用的方法

public class ImageNiver {
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;
        }

        // This offers some additional logic in case the image has a strange
        // aspect ratio. For example, a panorama may have a much larger
        // width than height. In these cases the total pixels might still
        // end up being too large to fit comfortably in memory, so we should
        // be more aggressive with sample down the image (=larger inSampleSize).

        long totalPixels = width * height / inSampleSize;

        // Anything more than 2x the requested pixels we'll sample down further
        final long totalReqPixelsCap = reqWidth * reqHeight * 2;

        while (totalPixels > totalReqPixelsCap) {
            inSampleSize *= 2;
            totalPixels /= 2;
        }

    }

    return inSampleSize;
}

public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
                                                     int reqWidth, int 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);
}

}

我一直在寻找解决方案好几天了，但是找不到这个问题的答案。

Answer 1

在这一行：

image.setImageBitmap(ImageNiver.decodeSampledBitmapFromResource(getResources(),R.id.step2pointaprob4exc2img,reqwidth1,reqheight1));

两次查看此R.id.step2pointaprob4exc2img

您应该在资源（实际图片）中传递图片的ID，而不是像在此那样传递imageView的ID。