android 全局彈窗，android全局livedata,Android 使用ViewModel，LiveData高效、簡

一、思路

ViewModel作為View監聽器和View進行綁定，LiveData數據存放在ViewModel數據持久化，并具有觀察性。View通過監聽LiveData的數據變化，進行相應的UI操作。

UserRepository作為數據來源層，可以是本地數據庫SqlLite,本地文件，網絡數據

二、核心代碼

android 全局彈窗？1、ViewModel

package com.example.viewmodel_livedata.viewmodel;

import com.example.viewmodel_livedata.bean.LoginBean;

import com.example.viewmodel_livedata.repository.UserRepository;

import androidx.lifecycle.MediatorLiveData;

全局上下、import androidx.lifecycle.ViewModel;

public class UserViewModel extends ViewModel {

public MediatorLiveData liveData = new MediatorLiveData<>();

private UserRepository userRepository = new UserRepository();

/**

Android view？* 請求登錄

*

* @param userName

* @param pwd

*/

android viewmodel、public void requestLogin(String userName, String pwd) {

liveData.setValue(userRepository.execueLogin(userName, pwd));

}

}

2、Repository

android p？package com.example.viewmodel_livedata.repository;

import com.example.viewmodel_livedata.bean.LoginBean;

public class UserRepository {

/**

* 模擬 服務器登錄

android全局代理？* @param userName

* @param pwd

* @return

*/

public LoginBean execueLogin(String userName, String pwd) {

mediatorlivedata、if ("123".equals(userName) && pwd.equals("456")) {

return new LoginBean(200, " 登錄成功");

} else {

return new LoginBean(400, " 登錄失敗");

}

android、}

}

3、View

package com.example.viewmodel_livedata;

import android.os.Bundle;

android全局接收登陸、import android.view.View;

import android.widget.Toast;

import com.example.viewmodel_livedata.bean.LoginBean;

import com.example.viewmodel_livedata.viewmodel.UserViewModel;

import androidx.appcompat.app.AppCompatActivity;

Android登陸全局，import androidx.lifecycle.Observer;

import androidx.lifecycle.ViewModelProviders;

public class MainActivity extends AppCompatActivity {

private UserViewModel viewModel;

@Override

Android登錄通知全局，protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

viewModel = ViewModelProviders.of(this).get(UserViewModel.class);

viewModel.liveData.observe(this, new Observer() {

android自定義viewgroup、@Override

public void onChanged(LoginBean loginBean) {

Toast.makeText(MainActivity.this, loginBean.toString(), Toast.LENGTH_LONG).show();

}

});

}

public void login(View view) {

viewModel.requestLogin("123","4567");

}

}

三、源碼傳送門