Question

我正在获取一个网址并在Imageview中显示它。我的设备的自动启动是开启的。我希望imageview在旋转后根据设备的宽度进行缩放。

我可以从网址获取图片吗？

Answer 1

如果图像在远处调整，看起来不正确，或者您只想更好地控制旋转时发生的事情，也可以在代码中执行此操作。

首先获取设备的宽度和高度：

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

然后您可以使用该信息调整图像大小。

您可以设置o.inJustDecodeBounds = true来获取图像大小而不加载图像。如果图像很大，可以调整大小。下面的示例代码。

private Bitmap getBitmap(String path) {

Uri uri = getImageUri(path);
InputStream in = null;
try {
final int IMAGE_MAX_SIZE = 1200000; // 1.2MP
in = mContentResolver.openInputStream(uri);

// Decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(in, null, o);
in.close();



int scale = 1;
while ((o.outWidth * o.outHeight) * (1 / Math.pow(scale, 2)) > 
      IMAGE_MAX_SIZE) {
   scale++;
}
Log.d(TAG, "scale = " + scale + ", orig-width: " + o.outWidth + ", 
   orig-height: " + o.outHeight);

Bitmap b = null;
in = mContentResolver.openInputStream(uri);
if (scale > 1) {
    scale--;
    // scale to max possible inSampleSize that still yields an image
    // larger than target
    o = new BitmapFactory.Options();
    o.inSampleSize = scale;
    b = BitmapFactory.decodeStream(in, null, o);

    // resize to desired dimensions
    int height = b.getHeight();
    int width = b.getWidth();
    Log.d(TAG, "1th scale operation dimenions - width: " + width + ",
       height: " + height);

    double y = Math.sqrt(IMAGE_MAX_SIZE
            / (((double) width) / height));
    double x = (y / height) * width;

    Bitmap scaledBitmap = Bitmap.createScaledBitmap(b, (int) x, 
       (int) y, true);
    b.recycle();
    b = scaledBitmap;

    System.gc();
} else {
    b = BitmapFactory.decodeStream(in);
}
in.close();

Log.d(TAG, "bitmap size - width: " +b.getWidth() + ", height: " + 
   b.getHeight());
return b;
} catch (IOException e) {
Log.e(TAG, e.getMessage(),e);
return null;
}

在自动旋转时缩放Imageview

1 个答案: