将图片转换成一个ImageView大小，如何获取这个ImageView的大小
从开源项目ImageLoader中摘出：
/**
* Defines image size for loading at memory (for memory economy) by {@link ImageView} parameters.<br />
* Size computing algorithm:<br />
* 1) Get <b>maxWidth</b> and <b>maxHeight</b>. If both of them are not set then go to step #2.<br />
* 2) Get <b>layout_width</b> and <b>layout_height</b>. If both of them haven't exact value then go to step #3.</br>
* 3) Get device screen dimensions.
*/
private ImageSize getImageSizeScaleTo(ImageView imageView) {
int width = -1;
int height = -1;
// Check maxWidth and maxHeight parameters
try {
Field maxWidthField = ImageView.class.getDeclaredField("mMaxWidth");
Field maxHeightField = ImageView.class.getDeclaredField("mMaxHeight");
maxWidthField.setAccessible(true);
maxHeightField.setAccessible(true);
int maxWidth = (Integer) maxWidthField.get(imageView);
int maxHeight = (Integer) maxHeightField.get(imageView);
if (maxWidth >= 0 && maxWidth < Integer.MAX_VALUE) {
width = maxWidth;
}
if (maxHeight >= 0 && maxHeight < Integer.MAX_VALUE) {
height = maxHeight;
}
} catch (Exception e) {
Log.e(TAG, e.getMessage(), e);
}
if (width < 0 && height < 0) {
// Get layout width and height parameters
LayoutParams params = imageView.getLayoutParams();
width = params.width;
height = params.height;
}
if (width < 0 && height < 0) {
// Get device screen dimensions
width = configuration.maxImageWidthForMemoryCache;
height = configuration.maxImageHeightForMemoryCache;
// Consider device screen orientation
int screenOrientation = imageView.getContext().getResources().getConfiguration().orientation;
if ((screenOrientation == Configuration.ORIENTATION_PORTRAIT && width > height)
|| (screenOrientation == Configuration.ORIENTATION_LANDSCAPE && width < height)) {
int tmp = width;
width = height;
height = tmp;
}
}
return new ImageSize(width, height);
}
