3.5 第一次个人作业

Login.java

package com.example.tiwenzhuce;

import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import java.util.Map;


public class Login extends AppCompatActivity {
    private Button mBtnLogin;
    private EditText mEtUserName;//声明空间
    private EditText et_1;
    private EditText et_2;
    private String strname;
    private String strpasswd;
    private SharedHelper sh;
    private Context mContext;
    private Button mBtnzhuce1;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        mContext = getApplicationContext();
        sh = new SharedHelper(mContext);
        et_1=findViewById(R.id.et_1);
        et_2=findViewById(R.id.et_2);

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);
        mBtnLogin = findViewById(R.id.btn_login);
        mBtnzhuce1=findViewById(R.id.btn_zh_1);//查找
        mBtnLogin.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v){
                strname=et_1.getText().toString();
                strpasswd=et_2.getText().toString();
                sh.save(strname,strpasswd);
                Toast.makeText(Login.this,"登录成功!",Toast.LENGTH_SHORT).show();
                Intent intent = new Intent(Login.this,TiWenzhuce.class);
    startActivity(intent);
}
        });
                mBtnzhuce1.setOnClickListener(new View.OnClickListener()
                {
@Override
public void onClick(View v){
        Intent intent =new Intent(Login.this,zhuceActivity.class);
        startActivity(intent);
        }
        });

        mEtUserName = findViewById(R.id.et_1);//监听事件
        mEtUserName.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {

        }

@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
        Log.d("edittext",s.toString());
        }

@Override
public void afterTextChanged(Editable s) {

        }
        });
        }
@Override
protected void onStart() {
        super.onStart();
        Map<String,String> data = sh.read();
        et_1.setText(data.get("username"));
        et_2.setText(data.get("passwd"));
        }
        }

activity_login

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="15dp">
    <EditText
        android:id="@+id/et_1"
        android:layout_width="match_parent"
        android:textSize="16sp"
        android:hint="用户名："
        android:drawableLeft="@drawable/yonghum"
        android:background="@drawable/bg_username"
        android:paddingLeft="10dp"
        android:maxLines="1"
        android:drawablePadding="7dp"
        android:layout_marginTop="25dp"
        android:layout_height="50dp"/>
    <EditText
        android:id="@+id/et_2"
        android:layout_width="match_parent"
        android:textSize="16sp"
        android:hint="密码："
        android:inputType="textPassword"
        android:layout_below="@id/et_1"
        android:layout_height="50dp"
        android:drawableLeft="@drawable/mimasuo"
        android:maxLines="1"
        android:layout_marginTop="25dp"
        android:drawablePadding="7dp"
        android:background="@drawable/bg_username"
        android:paddingLeft="10dp"/>
    <Button
        android:id="@+id/btn_login"
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:layout_below="@id/et_2"
        android:layout_marginTop="25dp"
        android:text="登录"
        android:textSize="25sp"
        android:textColor="#fff"
        android:background="@drawable/bg_btn4"/>

    <Button
        android:id="@+id/btn_zh_1"
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:layout_below="@id/btn_login"
        android:layout_marginTop="25dp"
        android:text="注册"
        android:textSize="25sp"
        android:textColor="#fff"
        android:background="@drawable/bg_btn4"/>
</RelativeLayout>