Android实现购物车及其他功能的角标-创新互联

1.先来张效果图

2.自定义一个角标工具类BottomBarView 。

**
 * Created by Administrator on 2016/12/27.
 * 角标工具类
 */
public class BottomBarView extends RelativeLayout {
 private Context context;
 private TextView bar_num;
 private int count = 0;
 public BottomBarView(Context context) {
 this(context, null);
 }
 public BottomBarView(Context context, AttributeSet attrs) {
 this(context, attrs, 0);
 }
 public BottomBarView(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);
 this.context = context;
 RelativeLayout rl = (RelativeLayout) LayoutInflater.from(context).inflate(R.layout.bottom_bar_view, this, true);
 bar_num = (TextView) rl.findViewById(R.id.bar_num);
 bar_num.setVisibility(GONE);
 }
 public void add() {
 bar_num.setVisibility(VISIBLE);
 count++;
 if (count < 100) {
 bar_num.setText(count + "");
 } else {
 bar_num.setText("99+");
 }
 }
 public void add(int n) throws Exception {
 if(n<0){
 throw new Exception(BottomBarView.class.getSimpleName()+" add(int n).The param must be a positive num");
 }
 bar_num.setVisibility(VISIBLE);
 count += n;
 if (count < 100) {
 bar_num.setText(count + "");
 } else {
 bar_num.setText("99+");
 }
 }
 public void delete() {
 if (count == 0) {
 bar_num.setVisibility(GONE);
 } else {
 count--;
 if (count == 0) {
 bar_num.setVisibility(GONE);
 } else if (count > 0 && count < 100) {
 bar_num.setVisibility(VISIBLE);
 bar_num.setText(count + "");
 } else {
 bar_num.setVisibility(VISIBLE);
 bar_num.setText("99+");
 }
 }
 }
 public void deleteAll() {
 count = 0;
 bar_num.setVisibility(GONE);
 }
}