Deep copy of a Drawable

问题

I have an ImageView. In its onClick I get its Drawable:

Drawable dr = ((ImageView) v).getDrawable();

And set it to a dialog's ImageView:

zoomedImage.setImageDrawable(dr);

But when I close the dialog or the activity is resumed. The image at the original position gets stretched and is shown larger than its size, leading to only a portion of the image is visible in the ImageView.

Is this a case of deep copy or there is another problem? If it is, how can do I deep copy the original Drawable so that I could set the copy to zoomed image?

Thanks in advance.

回答1:

Finally I succeed! I had similar problem, when I used color filter on my drawable it changed the drawable, its very close to the solution of the other people here, but only this worked for me:

Drawable drwNewCopy = dr.getConstantState().newDrawable().mutate();

回答2:

I managed to copy the drawable using following code:

drawable.mutate().getConstantState().newDrawable();

Here mutate() makes the drawable mutable to avoid sharing its state, and getConstantState().newDrawable() creates a new copy.

Thus different ImageViews use different drawables and there's no stretching.

回答3:

Use BitmapFactory to convert the drawable into bitmap separately make or perform changes on it.

回答4:

You should probably call dr.clone and then call mutate() on the object

This will make the drawable not share any state

Drawable newdr = dr.clone();
newdr = newdr.mutate();

Edit: Maybe just

Drawable  newdr = dr.mutate();

will work. Give both a try

来源：https://stackoverflow.com/questions/13064473/deep-copy-of-a-drawable