第十一、十二周作业
图片一 用内部存储实现文件写入和读取功能
<?xml version="1.0" encoding="utf-8"?> <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"> <EditText android:id="@+id/et1" android:layout_width="match_parent" android:layout_height="wrap_content" android:hint="输入你想输入的内容"/> <Button android:id="@+id/bt1" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="写入" android:textColor="#FFFFFF" android:background="#000" android:onClick="click1"/> <EditText android:id="@+id/et2" android:layout_width="match_parent" android:layout_height="wrap_content" android:hint="显示读取的内容"/> <Button android:id="@+id/bt2" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="读取" android:textColor="#FFFFFF" android:background="#000" android:onClick="click2"/> </LinearLayout>
package com.example.dell.myapplication1; import android.os.Bundle; import android.support.v7.app.ActionBarActivity; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.EditText; import android.widget.Toast; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; public class MainActivity1 extends ActionBarActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main1); findViewById(R.id.bt1); findViewById(R.id.bt2); EditText editText1 = (EditText) findViewById(R.id.et1); EditText editText2 = (EditText) findViewById(R.id.et2); } public void click1(View view) { EditText editText1 = (EditText) findViewById(R.id.et1); EditText editText2 = (EditText) findViewById(R.id.et2); String fileName = "data.txt"; String context = editText1.getText().toString(); FileOutputStream fos = null; try { fos = openFileOutput(fileName, MODE_PRIVATE); fos.write(context.getBytes()); } catch (Exception e) { e.printStackTrace(); } finally { if (fos != null) { try { fos.close(); } catch (IOException e) { e.printStackTrace(); } } } Toast.makeText(this, "保存成功", Toast.LENGTH_SHORT).show(); } public void click2(View view) { EditText editText2 = (EditText) findViewById(R.id.et2); String context = ""; FileInputStream fis = null; try { fis = openFileInput("data.txt"); byte[] buffer = new byte[fis.available()]; fis.read(buffer); context = new String(buffer); } catch (Exception e) { e.printStackTrace(); } finally { if (fis != null) { try { fis.close(); } catch (IOException e) { e.printStackTrace(); } } } editText2.setText(context); } }
图片二 使用sharedpreference实现记住密码功能
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout 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: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.dell.text12_2.text12"> <TextView android:id="@+id/tv_1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="账号" android:textColor="#000000" android:textSize="20sp" android:layout_marginTop="30dp" android:layout_marginLeft="20dp" android:padding="10dp"/> <EditText android:id="@+id/et_1" android:layout_width="match_parent" android:layout_height="wrap_content" android:hint="请输入用户名" android:layout_toRightOf="@id/tv_1" android:layout_marginTop="30dp" android:padding="10dp" android:textSize="20sp"/> <TextView android:id="@+id/tv_2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="密码" android:textColor="#000000" android:textSize="20sp" android:layout_marginTop="30dp" android:layout_marginLeft="20dp" android:layout_below="@id/tv_1" android:padding="10dp"/> <EditText android:id="@+id/et_2" android:layout_width="match_parent" android:layout_height="wrap_content" android:hint="请输入密码" android:layout_toRightOf="@id/tv_2" android:layout_below="@id/et_1" android:layout_marginTop="30dp" android:padding="10dp" android:textSize="20sp"/> <EditText android:id="@+id/text1" android:layout_width="match_parent" android:layout_height="400dp" /> <CheckBox android:id="@+id/cb_1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="记住密码" android:textColor="#000000" android:textSize="18sp" android:layout_below="@id/tv_2" android:padding="5dp" android:layout_marginTop="30dp" android:layout_marginLeft="20dp" /> <CheckBox android:id="@+id/cb_2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="自动登录" android:textColor="#000000" android:textSize="18sp" android:layout_below="@id/tv_2" android:layout_toRightOf="@id/cb_1" android:padding="5dp" android:layout_marginTop="30dp" android:layout_marginLeft="20dp" /> <Button android:id="@+id/btn_1" android:layout_width="500dp" android:layout_height="wrap_content" android:text="登录" android:textColor="#000000" android:textSize="18sp" android:layout_below="@id/text1" android:padding="5dp" android:layout_marginTop="25dp" android:layout_marginLeft="20dp" android:layout_toRightOf="@id/cb_2" /> </RelativeLayout>
package com.example.dell.text12_2; import android.os.Bundle; import android.support.v7.app.ActionBarActivity; import android.text.TextUtils; import android.view.View; import android.widget.Button; import android.widget.CheckBox; import android.widget.CompoundButton; import android.widget.EditText; import android.widget.Toast; import java.util.Map; public class text12 extends ActionBarActivity implements android.view.View.OnClickListener, CompoundButton.OnCheckedChangeListener { private EditText et_account; private EditText et_password; private Button btn_login; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_text12); initView(); Map<String,String> userInfo=saveQQ.getUserInfo(this); if(userInfo!=null){ et_account.setText(userInfo.get("account")); et_password.setText(userInfo.get("password")); } } private void initView() { et_account= (EditText) findViewById(R.id.et_1); et_password= (EditText) findViewById(R.id.et_2); btn_login= (Button) findViewById(R.id.btn_1); btn_login.setOnClickListener(this); CheckBox cb1= (CheckBox) findViewById(R.id.cb_1); cb1.setOnCheckedChangeListener(this); CheckBox cb2= (CheckBox) findViewById(R.id.cb_2); cb2.setOnCheckedChangeListener(this); } @Override public void onClick(View view) { switch (view.getId()){ case R.id.btn_1: String account=et_account.getText().toString().trim(); String password=et_password.getText().toString(); if(TextUtils.isEmpty(account)){ Toast.makeText(this, "请输入账号", Toast.LENGTH_LONG).show(); return; } if(TextUtils.isEmpty(password)){ Toast.makeText(this,"请输入密码",Toast.LENGTH_LONG).show(); return; } Toast.makeText(this,"登录成功",Toast.LENGTH_LONG).show(); } } @Override public void onCheckedChanged(CompoundButton compoundButton, boolean b) { switch (compoundButton.getId()){ case R.id.cb_1: String account=et_account.getText().toString().trim(); String password=et_password.getText().toString(); boolean isSaveSuccess=saveQQ.saveUserInfo(this,account,password); if(isSaveSuccess&&b){ Toast.makeText(this,"保存成功",Toast.LENGTH_LONG).show(); }else { Toast.makeText(this,"保存失败",Toast.LENGTH_LONG).show(); et_account.setText(null); et_password.setText(null); } break; case R.id.cb_2: account=et_account.getText().toString().trim(); password=et_password.getText().toString(); if(TextUtils.isEmpty(account)){ Toast.makeText(this,"请输入账号",Toast.LENGTH_LONG).show(); return; } if(TextUtils.isEmpty(password)){ Toast.makeText(this,"请输入密码",Toast.LENGTH_LONG).show(); return; } if(b) Toast.makeText(this,"登录成功",Toast.LENGTH_LONG).show(); else { Toast.makeText(this,"请登录",Toast.LENGTH_LONG).show(); } } } }
package com.example.dell.text12_2; import java.util.HashMap; import java.util.Map; import android.content.Context; import android.content.SharedPreferences; /** * Created by dell on 2021/10/31. */ public class saveQQ { public static boolean saveUserInfo(Context context,String account,String password ){ SharedPreferences sp=context.getSharedPreferences("data", context.MODE_PRIVATE); SharedPreferences.Editor editor=sp.edit(); editor.putString("Username", account); editor.putString("pwd", password); editor.commit(); return true; } public static Map<String, String> getUserInfo(Context context){ SharedPreferences sp=context.getSharedPreferences("data", context.MODE_PRIVATE); String account=sp.getString("Username", null); String password=sp.getString("pwd", null); Map<String, String> userMap=new HashMap<String,String>(); userMap.put("account", account); userMap.put("password", password); return userMap; } }