第一周第二周知识点整理归纳

一、安装 配置开发环境

• 安装模拟器
• 创建第一个项目

二、构建基本页面

• 基本控件的使用

1.TextView
2.Button
3.EditText
4.ImageView
...

• 页面间的跳转

点击注册按钮跳转到注册页面

Button tvRegister = findViewById(R.id.register_login);
        tvRegister.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent =new Intent(LoginActivity.this,RegisterActivity.class);
                startActivity(intent);
            }
        });

• Toolbar顶部导航栏的设置

activity_login.xml

<include layout="@layout/tool_bar" />

LoginActivity.java

private void initToolbar(){
        toolbar = findViewById(R.id.title_toolbar);
        toolbar.setTitle("登录");
        setSupportActionBar(toolbar);

        ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);//设置返回键
//            actionBar.setHomeButtonEnabled(true);//设置是否是首页
        }
        toolbar.setNavigationOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                LoginActivity.this.finish();
            }
        });
    }

三、登录、注册功能的实现

验证用户名、密码正确后登录成功并跳转到我的页面

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);
        initToolbar();
        initView();
        initData();
        btnLogin.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v){
                String username=etUsername.getText().toString();
                String password=etPassword.getText().toString();
                SharedPreferences pref = getSharedPreferences("data", MODE_PRIVATE);
                String name = pref.getString("username", "");
                String pwd = pref.getString("password", "");
                if (TextUtils.isEmpty(username)) {
                    Toast.makeText(LoginActivity.this, "用户名不能为空", Toast.LENGTH_SHORT).show();
                } else if (TextUtils.isEmpty(password)) {
                    Toast.makeText(LoginActivity.this, "密码不能为空", Toast.LENGTH_SHORT).show();
//                } else if (!username.equals(name)) {
//                    Toast.makeText(LoginActivity.this, "用户名错误"+username+","+name , Toast.LENGTH_SHORT).show();
                } else if (!MD5Utils.md5(password).equals(pwd)) {
                    Toast.makeText(LoginActivity.this, "密码错误", Toast.LENGTH_SHORT).show();
                } else {
                    Toast.makeText(LoginActivity.this, "登录成功", Toast.LENGTH_SHORT).show();
                    saveLoginStatus(username,true);

                    //返回我的界面
                    Intent intent = new Intent();
                    intent.putExtra("isLogin" , true);
                    intent.putExtra("longinUser",username);
                    setResult(RESULT_OK,intent);
                    LoginActivity.this.finish();
                }
            }
        });
    }

四、底部菜单栏

将导航栏固定在页面的底部

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:id="@+id/main_body"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@android:color/white"
        android:orientation="vertical">

    </LinearLayout>

    <RadioGroup
        android:id="@+id/btn_group"
        android:layout_width="match_parent"
        android:layout_height="56dp"
        android:layout_alignParentBottom="true"
        android:background="#F2F2F2"
        android:orientation="horizontal">

        <RadioButton
            android:id="@+id/btn_course"
            style="@style/TabMenuItem"
            android:drawableTop="@drawable/selector_nav_course"
            android:text="课程" />

        <RadioButton
            android:id="@+id/btn_execise"
            style="@style/TabMenuItem"
            android:drawableTop="@drawable/selector_nav_execise"
            android:text="习题" />

        <RadioButton
            android:id="@+id/btn_message"
            style="@style/TabMenuItem"
            android:drawableTop="@drawable/selector_nav_message"
            android:text="资讯" />

        <RadioButton
            android:id="@+id/btn_my"
            style="@style/TabMenuItem"
            android:drawableTop="@drawable/selector_nav_my"
            android:checked="true"
            android:text="我" />
    </RadioGroup>

</RelativeLayout>

六、退出登录功能的实现

退出登录后，清空保存的用户信息

 // 退出登录
       exitLayout.setOnClickListener(new View.OnClickListener() {
           @Override
           public void onClick(View v) {
               Toast.makeText(SettingActivity.this, "退出登录", Toast.LENGTH_SHORT).show();

               new AlertDialog.Builder(SettingActivity.this)
                       .setTitle("退出")
                       .setMessage("确认退出登录？")
                       .setPositiveButton("确认", new DialogInterface.OnClickListener() {
                           @Override
                           public void onClick(DialogInterface dialog, int which) {
                               SharedUtils.clearLoginInfo(SettingActivity.this);

                               // 返回我的界面
                               Intent intent = new Intent();
                               intent.putExtra("isLogin", false);
                               setResult(RESULT_OK, intent);
                               SettingActivity.this.finish();
                           }
                       })
                       .setNegativeButton("取消", new DialogInterface.OnClickListener() {
                           @Override
                           public void onClick(DialogInterface dialog, int which) {
                               dialog.dismiss();
                           }
                       })
                       .show();

           }
       });