Android：如何将图像资源与 R.drawable.imagename 进行比较？

Question

I am working on a sample application in which I need to get the resource of an image view in a onClick listener and compare that with the image source that I know exists. If the resources are the same, I want to launch another intent. The problem I am facing right now is to access that ImageView (and hence its resource Id integer) to compare to the drawable resource.

@Override
// should int be final ??
public View getView(final int position, View convertView, ViewGroup parent) {

    ImageView imageView;
    if (convertView == null) {  // if it's not recycled, initialize some attributes
        imageView = new ImageView(mContext);
        imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setPadding(8, 8, 8, 8);
    } else {
        imageView = (ImageView) convertView;
    }

    imageView.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) { 
// This is not working and I need to find a way to solve this >>
                if (((ImageView)v).getResources().getInteger(0) == R.drawable.imageToCompare)
                {
                    // do nothing
                }
                else
                {
                    // do something         
                }

Answer 1

You can't get a drawable id from an ImageView . But if you set it from code, you can also store it somewhere, for example in the tag field. Take a look at the similar question: Who I compare an background Image resource TextView with a R.drawable.bg_image for switch .

Answer 2

if(((ImageView)v).getDrawable().getConstantState() == MainActivity.this
                        .getResources().getDrawable(R.drawable.unlock)
                        .getConstantState()))
{

// Do Something
}

Answer 3

The proper way is to user setTag() and getTag . I guess you are making your own adapter.

In the method public View getView(int position, View convertView, ViewGroup parent) , you set tag to Imageview when you add other properties to it.

ImageView temp = (ImageView) v.findViewById(resId);
temp.setImageResource(icon);
temp.setTag(icon); //drawable unique ID will be my identifier here

Then in the onClick you simply compare View v with your drawable id. For example, I wanted to change image on click and I coded it this way. Take notice how I also change tag when I set a new drawable

        img.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                if ((Integer)v.getTag() == R.drawable.current_img) {
                    v.setBackgroundResource(R.drawable.new_img);
                    v.setTag(R.drawable.new_img);
                } 
            }
        });