获取ImageView中图像的显示大小

Question

代码很简单:

<ImageView android:layout_width="fill_parent"
           android:layout_height="fill_parent"
           android:src="@drawable/cat"/>

注意ImageView用于fill_parent宽度和高度.

图像cat是一个小图像,它将放大以适合ImageView,并同时保持宽高比.

我的问题是如何获得图像的显示尺寸？我试过了:

imageView.getDrawable().getIntrinsicHeight()

但它是图像的原始高度cat.

我试过了:

imageView.getDrawable().getBounds()

但哪个回归Rect(0,0,0,0).

Answer 1

以下将有效:

ih=imageView.getMeasuredHeight();//height of imageView
iw=imageView.getMeasuredWidth();//width of imageView
iH=imageView.getDrawable().getIntrinsicHeight();//original height of underlying image
iW=imageView.getDrawable().getIntrinsicWidth();//original width of underlying image

if (ih/iH<=iw/iW) iw=iW*ih/iH;//rescaled width of image within ImageView
else ih= iH*iw/iW;//rescaled height of image within ImageView

(iw x ih)现在表示视图中图像的实际重新缩放(宽度x高度)(换句话说,显示图像的大小)

编辑:我认为一个更好的方式来编写上面的答案(和一个使用int的答案):

            final int actualHeight, actualWidth;
            final int imageViewHeight = imageView.getHeight(), imageViewWidth = imageView.getWidth();
            final int bitmapHeight = ..., bitmapWidth = ...;
            if (imageViewHeight * bitmapWidth <= imageViewWidth * bitmapHeight) {
                actualWidth = bitmapWidth * imageViewHeight / bitmapHeight;
                actualHeight = imageViewHeight;
            } else {
                actualHeight = bitmapHeight * imageViewWidth / bitmapWidth;
                actualWidth = imageViewWidth;
            }

            return new Point(actualWidth,actualHeight);

Answer 2

这是一个帮助函数，用于获取imageView中图像的边界。

/**
 * Helper method to get the bounds of image inside the imageView.
 *
 * @param imageView the imageView.
 * @return bounding rectangle of the image.
 */
public static RectF getImageBounds(ImageView imageView) {
    RectF bounds = new RectF();
    Drawable drawable = imageView.getDrawable();
    if (drawable != null) {
        imageView.getImageMatrix().mapRect(bounds, new RectF(drawable.getBounds()));
    }
    return bounds;
}