用户登录系统

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:Android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    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.example.bz0209.myapplication.MainActivity"
    android:background="#8ECFE5"
    >

    <EditText
        android:hint="请输入账号"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_marginLeft="54dp"
        android:layout_marginStart="54dp"
        android:layout_marginTop="33dp"
        android:id="@+id/textView2"
        />

    <EditText
        android:text="请输入密码"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView2"
        android:layout_alignLeft="@+id/textView2"
        android:layout_alignStart="@+id/textView2"
        android:layout_marginTop="10dp"
        android:id="@+id/textView3" />

    <CheckBox
        android:text="记住密码"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/button"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_marginLeft="20dp"
        android:layout_marginStart="20dp"
        android:id="@+id/checkBox"
        android:layout_alignBottom="@+id/button" />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:srcCompat="@drawable/icon_user"
        android:layout_above="@+id/textView3"
        android:layout_toLeftOf="@+id/textView3"
        android:layout_toStartOf="@+id/textView3"
        android:id="@+id/imageView" />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:srcCompat="@drawable/icon_pass"
        android:layout_alignBottom="@+id/textView3"
        android:layout_toLeftOf="@+id/textView3"
        android:layout_toStartOf="@+id/textView3"
        android:id="@+id/imageView2" />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:srcCompat="@drawable/deer"
        android:id="@+id/imageView3"
        android:layout_below="@+id/button"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_marginRight="15dp"
        android:layout_marginEnd="15dp"
        android:layout_marginTop="12dp" />

    <Button
        android:text="登录"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="15dp"
        android:id="@+id/button"
        android:layout_below="@+id/textView3"
        android:layout_toRightOf="@+id/textView3"
        android:layout_marginLeft="47dp"
        android:layout_marginStart="47dp"
        android:layout_alignRight="@+id/imageView3"
        android:layout_alignEnd="@+id/imageView3"
        android:background="@drawable/btn"
        />
</RelativeLayout>
package com.example.bz0209.myapplication;

import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    private EditText editText1;
    private EditText editText2;
    private Button button;
    private CheckBox checkBox;
    SharedPreferences sharedPreferences;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        intView();
        sharedPreferences=getSharedPreferences("login",MODE_PRIVATE);
        boolean isRem=sharedPreferences.getBoolean("checkBox",false);
        if(isRem){
            String name=sharedPreferences.getString("name","");
            String pass=sharedPreferences.getString("pass","");
            editText1.setText(name);
            editText2.setText(pass);
            checkBox.isChecked(true);
        }
    }

    private void intView(){
        editText1=(EditText) findViewById(R.id.textView2);
        editText2=(EditText) findViewById(R.id.textView3);
        button=(Button) findViewById(R.id.button);
        checkBox=(CheckBox) findViewById(R.id.checkBox);
    }
    private void login(){
       String name=editText1.getText().toString();
        String pass=editText2.getText().toString();
        SharedPreferences.Editor editor=sharedPreferences.edit();
        if(checkBox.isChecked()){
            editor.putBoolean("checkBox",true);
            editor.putString("name",name);
            editor.putString("pass",pass);
        }
        else
            editor.clear();
        editor.commit();
        if("admin".equals(name)&&"pass".equals(pass)){
            Intent intent=new Intent(this,welcome.class);
            startActivity(intent);
            finish();
        }
        else
            Toast.makeText(this,"账号或密码错误",Toast.LENGTH_LONG).show();
    }




package com.example.bz0209.myapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class welcome extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_welcome);
    }

}