第八次作业

package com.example.myapplicationa;

import androidx.appcompat.app.AppCompatActivity ;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import java.io.FileInputStream;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    private EditText et_account;
    private EditText et_password;
    private Button btn;
    private SharedPreferences sp;
    private FileInputStream fi;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        et_account=(EditText) findViewById(R.id.et_account);
        et_password=(EditText) findViewById(R.id.et_password);
        btn=(Button) findViewById(R.id.btn);
        btn.setOnClickListener(this);

    }
    @Override
    public void onClick(View v) {
        String s1=et_account.getText().toString();
        String s2=et_password.getText().toString();
        if (TextUtils.isEmpty(s2+s1)) {
            Toast.makeText(this, "请输入QQ帐号", Toast.LENGTH_SHORT).show();
        }else {
            sp=getSharedPreferences("data.txt", MODE_PRIVATE);
            SharedPreferences.Editor editor=sp.edit();
            editor.putString("s1", null);
            editor.putString(s2, null);
            editor.commit();
            Toast.makeText(this, "登入成功", Toast.LENGTH_SHORT).show();

            String s3=sp.getString("s1", "");
            String s4=sp.getString("s2", "");
            Toast.makeText(this, "保存成功", Toast.LENGTH_SHORT).show();

        }

    }


}

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:background="#999999"
              android:orientation="vertical">
    <ImageView
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:layout_centerHorizontal="true"
            android:layout_gravity="center_horizontal"
            android:layout_marginTop="40dp"
            android:src="@drawable/qq" />
    <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="15dp"
            android:background="@android:color/white"
            android:orientation="horizontal">
        <TextView
                android:id="@+id/tv_account"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:padding="10dp"
                android:text="账号:"
                android:textColor="#000"
                android:textSize="30sp" />
        <EditText
                android:id="@+id/et_account"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginLeft="5dp"
                android:padding="10dp" />
    </LinearLayout>
    <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:background="@android:color/white"
            android:orientation="horizontal">
        <TextView
                android:id="@+id/tv_password"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:padding="10dp"
                android:text="密码:"
                android:textColor="#000"
                android:textSize="30sp" />
        <EditText
                android:id="@+id/et_password"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginLeft="5dp"
                android:inputType="textPassword"
                android:padding="10dp" />
    </LinearLayout>
    <Button
            android:id="@+id/btn"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="25dp"
            android:background="#3C5678"
            android:text="登录"
            android:textColor="@android:color/white"
            android:textSize="30sp" />
</LinearLayout>