前言：当我们写商城类的项目的时候，一般都会有加入购物车的功能，加入购物车的时候会有一些抛物线动画，最近做到这个功能，借助别人的demo写了一个。
效果：
开发环境：AndroidStudio2.1.2+gradle-2.10
涉及知识：1.沉浸式状态栏，2.单位精度计算(价格)，3.List之Iterator。
部分代码：
public class MainActivity extends AppCompatActivity implements FoodAdapter.FoodActionCallback {
private ListView listView;
private TextView goods_all_pricetv;
private TextView good_numtv;
private List<FoodModel> list;
private List<FoodModel> selectList = new ArrayList<>();
private FoodAdapter adapter = null;
@Override
protected void onCreate(@Nullable final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//沉浸式状态栏
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
//透明状态栏
getwindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
//透明导航栏
getwindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
}
listView = (ListView) findViewById(R.id.listView);
goods_all_pricetv = (TextView) findViewById(R.id.goods_all_pricetv);
good_numtv = (TextView) findViewById(R.id.good_numtv);
findViewById(R.id.goods_submit_tv).setonClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (null != selectList && selectList.size() > 0) {
Toast.makeText(MainActivity.this,"你一共加入购物车" + good_numtv.getText() +
"份商品,总价格为：" + goods_all_pricetv.getText(),Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this,"你的购物车为空",Toast.LENGTH_SHORT).show();
}
}
});
initData();
}
private void initData() {
list = AppConfig.factoryFoods();
adapter = new FoodAdapter(this,list,this);
listView.setAdapter(adapter);
}
//添加商品动画
@Override
public void addAction(View view,int item) {
ShoppingCartAnimationView shoppingCartAnimationView = new ShoppingCartAnimationView(this);
int position[] = new int[2];
view.getLocationInWindow(position);
shoppingCartAnimationView.setStartPosition(new Point(position[0],position[1]));
ViewGroup rootView = (ViewGroup) this.getwindow().getDecorView();
rootView.addView(shoppingCartAnimationView);
int endPosition[] = new int[2];
good_numtv.getLocationInWindow(endPosition);
shoppingCartAnimationView.setEndPosition(new Point(endPosition[0],endPosition[1]));
shoppingCartAnimationView.startBeizerAnimation();
FoodModel model = list.get(item);
model.setNum(model.getNum() + 1);
adapter.notifyDataSetChanged();
calculatePrice();
}
//减少商品
@Override
public void reduceGood(int position) {
FoodModel model = list.get(position);
model.setNum(model.getNum() - 1);
adapter.notifyDataSetChanged();
calculatePrice();
}
//购物车份数+总价格计算
private void calculatePrice() {
selectList.clear();
double price = 0;
int num = 0;
Iterator<FoodModel> iterator = list.iterator();
while (iterator.hasNext()) {
FoodModel model = iterator.next();
if (model.getNum() != 0) {
selectList.add(model);
price += model.getPrice() * model.getNum();
num += model.getNum();
}
}
goods_all_pricetv.setText("￥" + adapter.priceResult(price) + "元");
good_numtv.setText(num + "");
}
}
