NullPointerException 无法从 oppo 设备上的 drawable 中找到位图

Question

我正在尝试从 drawable 获取 imageview 并调整它的大小我当前的代码在所有设备上都有效，除了 oppo 设备它在 crop() 方法

中崩溃

我遇到的崩溃是在 crop() 方法的第一行，您可以在下面找到

Caused by: java.lang.NullPointerException:

我当前的代码是：

public Bitmap getTileBitmap(int id, int size) {
    String string = tileUrls.get(id);
    if (string.contains(Themes.URI_DRAWABLE)) {
        String drawableResourceName = string.substring(Themes.URI_DRAWABLE.length());
        int drawableResourceId = Shared.context.getResources().getIdentifier(drawableResourceName, "drawable", Shared.context.getPackageName());
        Bitmap bitmap = Utils.scaleDown(drawableResourceId, size, size);
        return Utils.crop(bitmap, size, size);

    }
    return null;
}


public static Bitmap crop(Bitmap source, int newHeight, int newWidth) {
    int sourceWidth = source.getWidth();
    int sourceHeight = source.getHeight();
    float xScale = (float) newWidth / sourceWidth;
    float yScale = (float) newHeight / sourceHeight;
    float scale = Math.max(xScale, yScale);
    float scaledWidth = scale * sourceWidth;
    float scaledHeight = scale * sourceHeight;
    float left = (newWidth - scaledWidth) / 2;
    float top = (newHeight - scaledHeight) / 2;
    RectF targetRect = new RectF(left, top, left + scaledWidth, top + scaledHeight);
    Bitmap dest = Bitmap.createBitmap(newWidth, newHeight, source.getConfig());
    Canvas canvas = new Canvas(dest);
    canvas.drawBitmap(source, null, targetRect, null);

    return dest;
}

编辑：添加了可能导致问题的缩放方法

public static Bitmap scaleDown(int resource, int reqWidth, int reqHeight) {
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(Shared.context.getResources(), resource);

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

    // Decode bitmap with inSampleSize set
    options.inJustDecodeBounds = false;
    return BitmapFactory.decodeResource(Shared.context.getResources(), resource, options);
}

到目前为止我不确定是什么导致了 oppo 设备上的崩溃

Answer 1

试试这个：

options.inJustDecodeBounds = true;
options.inScaled = false;
options.inDensity = 0;
options.inMutable = true; //API 11. Pass to canvas? Might crash without this.
//Load the image here... BitmapFactory.decodeResource()...

... //Some calculations.

options.inJustDecodeBounds = false;
options.inPreferredConfig = Bitmap.Config.ARGB_8888;

NullPointerException 无法从 oppo 设备上的 drawable 中找到位图

NullPointerException Cant find bitmap from drawable on oppo device

android

bitmap

drawbitmap