使用Favor库简化首选项

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Android

Favor是一个第三方库, 可以简化SharedPreferences, 使用依赖注入的方式声明. 我们根据常见的输入框, 把账户信息存在Favor的类中, 来看看这个库怎么用.

1. 准备

配置build.gradle

    compile 'com.cocosw:favor:0.2.0'
    compile 'com.jakewharton:butterknife:7.0.1'

布局, 输入账户和密码, 下面两行小字显示保存在SharedPreferences中的数据.

<LinearLayout
    ....>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/user_name_wrapper"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp">

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Username"
            android:inputType="textEmailAddress"/>
    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/password_wrapper"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp">

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Password"
            android:inputType="textPassword"/>
    </android.support.design.widget.TextInputLayout>

    <Button
        android:id="@+id/commit_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="8dp"
        android:background="@color/colorAccent"
        android:text="登录"
        android:textColor="@android:color/white"/>

    <TextView
        android:id="@+id/user_name_show"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:text="username"/>

    <TextView
        android:id="@+id/password_show"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="password"/>

</LinearLayout>

使用TextInputLayout来绘制输入框.

页面逻辑, 验证邮箱和密码, 当输入正确时, 保存在SharedPreference里面, 并显示, 使用Favor库进行保存.

public class MainActivity extends AppCompatActivity {

    private static final String EMAIL_PATTERN = "^[a-zA-Z0-9#_~!$&'()*+,;=:.\"(),:;<>@\\[\\]\\\\]+@[a-zA-Z0-9-]+(\\.[a-zA-Z0-9-]+)*$";

    @Bind(R.id.user_name_wrapper) TextInputLayout mUserNameWrapper;
    @Bind(R.id.password_wrapper) TextInputLayout mPasswordWrapper;
    @Bind(R.id.user_name_show) TextView mUserNameShow;
    @Bind(R.id.password_show) TextView mPasswordShow;

    private Account mAccount; // 账户类

    @OnClick(R.id.commit_button) void commitAccount(View view) {
        hideKeyboard();

        String username = mUserNameWrapper.getEditText().getText().toString();
        String password = mPasswordWrapper.getEditText().getText().toString();

        if (!validateEmail(username)) {
            mUserNameWrapper.setError("邮箱地址错误");
        } else if (!validatePassword(password)) {
            mUserNameWrapper.setErrorEnabled(false);
            mPasswordWrapper.setError("密码错误");
            mPasswordWrapper.getEditText().setText("");
        } else {
            mUserNameWrapper.setErrorEnabled(false);
            mPasswordWrapper.setErrorEnabled(false);

            doLogin(username, password);
            mUserNameShow.setText(mAccount.getUserName());
            mPasswordShow.setText(mAccount.getPassword());
        }

    }

    private void doLogin(String username, String password) {
        mAccount.setUserName(username);
        mAccount.setPassword(password);
    }


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

        mAccount = new FavorAdapter.Builder(this).build().create(Account.class);

        mUserNameShow.setText(mAccount.getUserName());
        mPasswordShow.setText(mAccount.getPassword());
    }

    // 隐藏键盘
    private void hideKeyboard() {
        View view = getCurrentFocus();
        if (view != null) {
            ((InputMethodManager) getSystemService(INPUT_METHOD_SERVICE))
                    .hideSoftInputFromWindow(view.getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
        }
    }

    // 验证邮箱
    private boolean validateEmail(String email) {
        Pattern pattern = Pattern.compile(EMAIL_PATTERN);
        Matcher matcher = pattern.matcher(email);
        return matcher.matches();
    }

    // 验证密码
    private boolean validatePassword(String password) {
        return password.length() > 7;
    }

    ...
}

2. Favor

初始化Favor类, 传入Context和Favor类型的类.

mAccount = new FavorAdapter.Builder(this).build().create(Account.class);

Account类, 必须要设定set和get方法, 名称相同, 可以提供默认值.

@AllFavor
public interface Account {
    void setUserName(String userName);

    @Default("No Name") String getUserName();

    void setPassword(String password);

    @Default("000000") String getPassword();
}

设置Favor类

    private void doLogin(String username, String password) {
        mAccount.setUserName(username);
        mAccount.setPassword(password);
    }

使用Favor类

        mUserNameShow.setText(mAccount.getUserName());
        mPasswordShow.setText(mAccount.getPassword());

Github下载地址

声明Favor的Interface, 就可以方便地使用SharedPreferences了.
Enjoy it!