java - 如何在我的示例中正确应用 MVP 模式

Question

我决定学习 MVP 模式，在阅读了一些文章后，我想在我当前的项目中尝试一下。

我选择了一项 Activity ，并开始思考如何根据 MVP 规则将其解耦。最终我不知道该怎么做。这似乎是一个并不复杂的 Activity ，但我不知道

有人可以给我一些建议吗？

哪些方法必须位于演示者中，哪些方法必须留在当前 Activity 中，哪些方法必须位于界面中？

刚刚告诉我应该从谁开始。

这是我的课

public final class ActivityUserDataScreen extends AppCompatActivity implements InterfaceActivityUserDataScreen{

private static String gender;
private static int inputHeight;
private static int inputWeight;
private TextInputLayout tilUserName;
private int backPressedQ = 0;
private String avatarName;

private static final String MEN = "men";
private static final String WOMEN = "men";

private Context context;
private PresenterActivityUserDataScreen presenter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Fabric.with(this, new Crashlytics());
    setContentView(R.layout.activity_user_data_screen);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
    setSupportActionBar((Toolbar) findViewById(R.id.tool_bar));

    context = getApplicationContext();
    initNumberPicker();
    initVar();
    presenter = new PresenterActivityUserDataScreen(this);
}

private void initNumberPicker() {
    NumberPicker pickerHeight = (NumberPicker) findViewById(R.id.pickerHeight);
    UtilClass.setDividerColor(pickerHeight, UtilClass.getMyColor(context, R.color.ntz_color_yellow));
    pickerHeight.setOnValueChangedListener(changeListener);
    pickerHeight.setMaxValue(220);
    pickerHeight.setMinValue(130);
    pickerHeight.setValue(States.HEIGHT_DEFAULT);

    NumberPicker pickerWeight = (NumberPicker) findViewById(R.id.pickerWeight);
    UtilClass.setDividerColor(pickerWeight, UtilClass.getMyColor(context, R.color.ntz_color_yellow));
    pickerWeight.setOnValueChangedListener(changeListener);
    pickerWeight.setMaxValue(120);
    pickerWeight.setMinValue(35);
    pickerWeight.setValue(States.WEIGHT_DEFAULT);
}

private void initVar() {
    tilUserName = (TextInputLayout) findViewById(R.id.tilUserName);

    SwitchButton switchButton = (SwitchButton) findViewById(R.id.sb_custom);
    switchButton.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            if (isChecked){
                gender = WOMEN;
            }else {
                gender = MEN;
            }
        }
    });

    EditText etAvatarName = (EditText) findViewById(R.id.etAvatarName);
    etAvatarName.setText(getResources().getString(R.string.avatar));
}

private NumberPicker.OnValueChangeListener changeListener = new NumberPicker.OnValueChangeListener() {
    @Override
    public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
        switch (picker.getId()) {
            case R.id.pickerHeight:
                inputHeight = newVal;
                break;
            case R.id.pickerWeight:
                inputWeight = newVal;
                break;
        }
    }
};

@Override
public final void onBackPressed() {
    UtilClass.processClick(context);

    if (backPressedQ == 1) {
        backPressedQ = 0;
        super.onBackPressed();
        overridePendingTransition(R.anim.open_main, R.anim.close_next);

    } else {
        backPressedQ++;
        Toast.makeText(this, "Press again to exit", Toast.LENGTH_SHORT).show();
    }

    //Обнуление счётчика через 5 секунд
    final Handler handler = new Handler();
    handler.postDelayed(new Runnable() {
        @Override
        public void run() {
            backPressedQ = 0;
        }
    }, 5000);
}

public final void goNext(View view) {
    UtilClass.processClick(context);
    EditText editText = tilUserName.getEditText();
    Editable editable = null;
    if (editText != null) {
        editable = editText.getText();
    }
    if (editable != null) {
        avatarName = editable.toString();
    }
    if (!isValidAvatarName()) return;

    saveUserData();
    MetadataSaver saver = new MetadataSaver(context);
    saver.saveFirstUserInfo();
    saver.saveDeviceInfo();
    PreferencesHelper.savePref(context, States.STILL_NOT_FINISH, true);
    UtilClass.goToNextActivity(ActivityUserDataScreen.this, ActivityVideo.class);
}

private void saveUserData(){
    saveAvatarGender();
    saveAvatarHeight();
    saveAvatarWeight();
    saveAvatarName();
}

private void saveAvatarGender(){
    if (gender == null){
        gender = MEN;
    }
    PreferencesHelper.savePref(context, States.AVATAR_GENDER, gender);
}

private boolean isValidAvatarName() {
    if (UtilClass.isTextEmpty(avatarName)) {
        tilUserName.setErrorEnabled(true);
        tilUserName.setError(getResources().getString(R.string.fill_your_avatar_name));
        return false;
    }

    if (avatarName.contains(" ")) {
        avatarName = avatarName.replace(" ", "");
    }

    if (!UtilClass.isLatinAlphabet(avatarName)) {
        tilUserName.setErrorEnabled(true);
        tilUserName.setError(getResources().getString(R.string.avatar_name_in_english));
        return false;
    }

    if (!UtilClass.isNameFree(context, avatarName)) {
        tilUserName.setErrorEnabled(true);
        tilUserName.setError(getResources().getString(R.string.avatar_name_already_in_use));
        return false;
    }

    return true;
}

private void saveAvatarHeight() {
    int result;
    if (inputHeight == 0) {
        result = States.HEIGHT_DEFAULT;
    } else {
        result = inputHeight;
    }

    PreferencesHelper.savePref(context, States.AVATAR_HEIGHT, result);
}

private void saveAvatarWeight() {
    int result;
    if (inputWeight == 0) {
        result = States.WEIGHT_DEFAULT;
    } else {
        result = inputWeight;
    }
    PreferencesHelper.savePref(context, States.AVATAR_WEIGHT, result);
}

private void saveAvatarName() {
    PreferencesHelper.savePref(context, States.AVATAR_NAME, avatarName);
}

public final void switchManWoman(View view) {
    UtilClass.processClick(context);
}
}

提前致谢!

Answer 1

需要考虑的事项是:

• View 需要尽可能简单。将其视为演示者给出的命令的执行者，并向演示者报告 UI 上发生的所有事情。界面应提供“显示此文本”等方法，和/或调用“单击按钮”等演示者的方法。

• 演示者是指挥者。它驱动您的 View 行为并对来自 View 本身的输入使用react。理想情况下，它应该从 Android 相关的任何内容中抽象出来，这样您就可以测试普通测试中的行为。