界面层
在这个Demo里,只有三个页面:登录页、注册页、券列表页。在这里,也会遵循界面篇提到的三个基本原则:规范性、单一性、简洁性。 首先,界面层需要调用核心层的Action,而这会在整个应用级别都用到,因此,Action的实例最好放在Application里。代码如下:
public class KApplication extends Application {
private AppAction appAction;
@Override
public void onCreate() {
super.onCreate();
appAction = new AppActionImpl(this);
}
public AppAction getAppAction() {
return appAction;
}
}
另外,一个Activity的基类也是很有必要的,可以减少很多重复的工作。基类的代码如下:
public abstract class KBaseActivity extends FragmentActivity {
// 上下文实例
public Context context;
// 应用全局的实例
public KApplication application;
// 核心层的Action实例
public AppAction appAction;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
context = getApplicationContext();
application = (KApplication) this.getApplication();
appAction = application.getAppAction();
}
}
再看看登录的Activity:
public class LoginActivity extends KBaseActivity {
private EditText phoneEdit;
private EditText passwordEdit;
private Button loginBtn;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
// 初始化View
initViews();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_login, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
// 如果是注册按钮
if (id == R.id.action_register) {
Intent intent = new Intent(this, RegisterActivity.class);
startActivity(intent);
return true;
}
return super.onOptionsItemSelected(item);
}
// 初始化View
private void initViews() {
phoneEdit = (EditText) findViewById(R.id.edit_phone);
passwordEdit = (EditText) findViewById(R.id.edit_password);
loginBtn = (Button) findViewById(R.id.btn_login);
}
// 准备登录
public void toLogin(View view) {
String loginName = phoneEdit.getText().toString();
String password = passwordEdit.getText().toString();
loginBtn.setEnabled(false);
this.appAction.login(loginName, password, new ActionCallbackListener<Void>() {
@Overridepublic void onSuccess(Void data) {
Toast.makeText(context, R.string.toast_login_success, Toast.LENGTH_SHORT).show();
Intent intent = new Intent(context, CouponListActivity.class);
startActivity(intent);
finish();
}
@Override
public void onFailure(String errorEvent, String message) {
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
loginBtn.setEnabled(true);
}
});
}
}
登录页的布局文件则如下:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.keegan.kandroid.activity.LoginActivity">
<EditText
android:id="@+id/edit_phone"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/edit_vertical_margin"
android:layout_marginBottom="@dimen/edit_vertical_margin"
android:hint="@string/hint_phone"
android:inputType="phone"
android:singleLine="true" />
<EditText
android:id="@+id/edit_password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/edit_vertical_margin"
android:layout_marginBottom="@dimen/edit_vertical_margin"
android:hint="@string/hint_password"
android:inputType="textPassword"
android:singleLine="true" />
<Button
android:id="@+id/btn_login"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/btn_vertical_margin"
android:layout_marginBottom="@dimen/btn_vertical_margin"
android:onClick="toLogin"
android:text="@string/btn_login" />
</LinearLayout>
可以看到,EditText的id命名统一以edit开头,而在Activity里的控件变量名则以Edit结尾。按钮的onClick也统一用toXXX的方式命名,明确表明这是一个将要做的动作。还有,string,dimen也都统一在相应的资源文件里按照相应的规范去定义。 注册页和登陆页差不多,这里就不展示代码了。主要再看看券列表页,因为用到了ListView,ListView需要添加适配器。实际上,适配器很多代码都是可以复用的,因此,我抽象了一个适配器的基类,代码如下:
public abstract class KBaseAdapter<T> extends BaseAdapter {
protected Context context;
protected LayoutInflater inflater;
protected List<T> itemList = new ArrayList<T>();
public KBaseAdapter(Context context) {
this.context = context;
inflater = LayoutInflater.from(context);
}
/**
* 判断数据是否为空
*
* @return 为空返回true,不为空返回false
*/
public boolean isEmpty() {
return itemList.isEmpty();
}
/**
* 在原有的数据上添加新数据
*
* @param itemList
*/
public void addItems(List<T> itemList) {
this.itemList.addAll(itemList);
notifyDataSetChanged();
}
/**
* 设置为新的数据,旧数据会被清空
*
* @param itemList
*/
public void setItems(List<T> itemList) {
this.itemList.clear();
this.itemList = itemList;
notifyDataSetChanged();
}
/**
* 清空数据
*/
public void clearItems() {
itemList.clear();
notifyDataSetChanged();
}
@Override
public int getCount() {
return itemList.size();
}
@Override
public Object getItem(int i) {
return itemList.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
abstract public View getView(int i, View view, ViewGroup viewGroup);
}
这个抽象基类集成了设置数据的方法,每个具体的适配器类只要再实现各自的getView方法就可以了。本Demo的券列表的适配器如下:
public class CouponListAdapter extends KBaseAdapter<CouponBO> {
public CouponListAdapter(Context context) {
super(context);
}
@Override
public View getView(int i, View view, ViewGroup viewGroup) {
ViewHolder holder;
if (view == null) {
view = inflater.inflate(R.layout.item_list_coupon, viewGroup, false);
holder = new ViewHolder();
holder.titleText = (TextView) view.findViewById(R.id.text_item_title);
holder.infoText = (TextView) view.findViewById(R.id.text_item_info);
holder.priceText = (TextView) view.findViewById(R.id.text_item_price);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
CouponBO coupon = itemList.get(i);
holder.titleText.setText(coupon.getName());
holder.infoText.setText(coupon.getIntroduce());
SpannableString priceString;
// 根据不同的券类型展示不同的价格显示方式
switch (coupon.getModelType()) {
default:
case CouponBO.TYPE_CASH:
priceString = CouponPriceUtil.getCashPrice(context, coupon.getFaceValue(), coupon.getEstimateAmount());
break;
case CouponBO.TYPE_DEBIT:
priceString = CouponPriceUtil.getVoucherPrice(context, coupon.getDebitAmount(), coupon.getMiniAmount());
break;
case CouponBO.TYPE_DISCOUNT:
priceString = CouponPriceUtil.getDiscountPrice(context, coupon.getDiscount(), coupon.getMiniAmount());
break;
}
holder.priceText.setText(priceString);
return view;
}
static class ViewHolder {
TextView titleText;
TextView infoText;
TextView priceText;
}
}
而券列表的Activity简单实现如下:
public class CouponListActivity extends KBaseActivity implements SwipeRefreshLayout.OnRefreshListener {
private SwipeRefreshLayout swipeRefreshLayout;
private ListView listView;
private CouponListAdapter listAdapter;
private int currentPage = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_coupon_list);
initViews();
getData();
// TODO 添加上拉加载更多的功能
}
private void initViews() {
swipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.swipe_refresh_layout);
swipeRefreshLayout.setOnRefreshListener(this);
listView = (ListView) findViewById(R.id.list_view);
listAdapter = new CouponListAdapter(this);
listView.setAdapter(listAdapter);
}
private void getData() {
this.appAction.listCoupon(currentPage, new ActionCallbackListener<List<CouponBO>>() {
@Override
public void onSuccess(List<CouponBO> data) {
if (!data.isEmpty()) {
if (currentPage == 1) { // 第一页
listAdapter.setItems(data);
} else { // 分页数据
listAdapter.addItems(data);
}
}
swipeRefreshLayout.setRefreshing(false);
}
@Override
public void onFailure(String errorEvent, String message) {
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
swipeRefreshLayout.setRefreshing(false);
}
});
}
@Override
public void onRefresh() {
// 需要重置当前页为第一页,并且清掉数据
currentPage = 1;
listAdapter.clearItems();
getData();
}
}
完结
终于写完了,代码也终于放上了github,为了让人更容易理解,因此很多都比较简单,没有再进行扩展。 github地址:https://github.com/keeganlee/kandroid