如何在微调器中添加一个小三角形？

Question

我在代码中看到了我自己的自定义适配器微调器。 一切正常，只是图像从左侧附加在每个值上，而只附加到选定的值。 在下图中，这是我得到的：

这是我的代码：

public class MyAdapter extends ArrayAdapter<String> {

    private Context context;
    private String[] values;

    public MyAdapter(Context ctx, int txtViewResourceId, String[] objects) {
        super(ctx, txtViewResourceId, objects);
        context = ctx;
        values = objects;
    }

    @Override
    public View getDropDownView(int position, View cnvtView, ViewGroup prnt) {
        return getCustomView(position, cnvtView, prnt);
    }
    @Override
    public View getView(int pos, View cnvtView, ViewGroup prnt) {
        return getCustomView(pos, cnvtView, prnt);
    }
    public View getCustomView(int position, View convertView,ViewGroup parent) {
        LayoutInflater inflater = LayoutInflater.from(context);
        View mySpinner = inflater.inflate(R.layout.custom_spinner, parent,
                false);
        TextView subSpinner = (TextView) mySpinner.findViewById(R.id.sub_text_seen);
        subSpinner.setText(values[position]);
        ImageView right_icon = (ImageView) mySpinner.findViewById(R.id.left_pic);


        return mySpinner;
    }
}

这是适配器的初始化：

spinnerduration.setAdapter(new MyAdapter(this, R.layout.custom_spinner, weeks_array));
    spinnerduration.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            /*TextView selectedText = (TextView) parent.getChildAt(0);
            if (selectedText != null) {
                selectedText.setTextColor(Color.WHITE);
            }*/
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {
            /*TextView selectedText = (TextView) parent.getChildAt(0);
            if (selectedText != null) {
                selectedText.setTextColor(Color.WHITE);
            }*/
        }
    });

Answer 1

您需要迭代可见项目，如果未选中它们，则应删除图像：

selectedItem.setCompoundDrawablesWithIntrinsicBounds(0, 0, 0, 0);

如果已选中，则需要设置三角形绘图：

selectedItem.setCompoundDrawablesWithIntrinsicBounds(R.drawable.icon, 0, 0, 0);