在Android中检查已应用的可绘制对象

Question

I want to check the Image button ( btn_a ), if it contain selected_image or unselected_image .

Then I want to change the selected_image to unselect_image or unselect_image to selected_image by the click of the Image Button.

My code so far:

        btn_a = (ImageButton) convertView.findViewById(R.id.button_a);
    btn_a.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            if(btn_a.getResources().getDrawable(R.id.button_a)==R.drawable.unselected_image){
                btn_a.setImageResource(R.drawable.selected_image);
                }else{
                btn_a.setImageResource(R.drawable.unselected_image);
                }

        }
    });

But this shows an error btn_a.getResources().getDrawable(R.id.button_a)==R.drawable.unselected_image .

Help me to implement this correctly.

EDIT :

@Override
public View getView(int position, View convertView, ViewGroup parent) {     
    if (convertView == null) {
        inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.list_view_cell, null);
    }
    btn_a = (ImageButton) convertView.findViewById(R.id.button_a);
    btn_a.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            Drawable drawable = favourite.getDrawable();
            if(drawable.getConstantState().equals(context.getResources().getDrawable(R.drawable.selected_image).getConstantState())){
                btn_a.setImageResource(R.drawable.unselected_image);
            }else{
                btn_a.setImageResource(R.drawable.selected_image);
            }
    return convertView;
}

Answer 1

Try this

hey Create context object first

In your Class Globally Declare this

Context context

then After add thiss

btn_a = (ImageButton) convertView.findViewById(R.id.button_a);
btn_a.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {
      Drawable drawable = btn_a.getDrawable();
     if (drawable.getConstantState().equals(context.getResources().getDrawable(R.drawable.unselected_image).getConstantState())){
   //Do your work here
      }
   }
});

Answer 2

Try this:

    btn_a = (ImageButton) convertView.findViewById(R.id.button_a);
    btn_a.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v)
        {
            Bitmap b1 = ((BitmapDrawable)btn_a.getDrawable()).getBitmap();
            Bitmap unselected_image = ((BitmapDrawable)context.getResources().getDrawable(R.drawable.unselected_image)).getBitmap();
            Bitmap selected_image = ((BitmapDrawable)context.getResources().getDrawable(R.drawable.selected_image)).getBitmap();
             // You will need minimum API level as 12 for using this sameAs function
            if(b1.sameAs(unselected_image))
            {
                btn_a.setImageResource(R.drawable.selected_image);
            }else{
                btn_a.setImageResource(R.drawable.unselected_image);
            }

        }
    });

This will solve your problem. I am comparing bitmaps here ..!!

EDIT 1:

Declare an Integer ArrayList :

 ArrayList<Integer> favList = new ArrayList<>();

Initialize it in your constructor :

    for (int i = 0; i < list.size() ; i++) {
        favList.add(R.drawable.unselected_image);
    }

Change your getView like this:

 @Override
public View getView(int position, View convertView, ViewGroup parent) {
    if (convertView == null) {
        inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.list_view_cell, null);
    }
    btn_a = (ImageButton) convertView.findViewById(R.id.button_a);
    btn_a.setTag(position);
    btn_a.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            Drawable drawable = favourite.getDrawable();
            if (drawable.getConstantState().equals(context.getResources().getDrawable(R.drawable.selected_image).getConstantState())) {
                favList.set((Integer)v.getTag(),R.drawable.unselected_image);
            } else {
                favList.set((Integer)v.getTag(),R.drawable.selected_image);
            }
            notifyDataSetChanged();

        }
    }
    favourite.setImageResource(favList.get(position));
    return convertView;
}