之前在做項(xiàng)目時(shí)用到了mvp模式腕够，由于時(shí)間緊，沒(méi)來(lái)得急進(jìn)行抽基礎(chǔ)類舌劳，趁現(xiàn)在有時(shí)間進(jìn)行整理一下帚湘，并對(duì)應(yīng)做下筆記，供以后方便使用甚淡。先扯一下M大诸、V、P作用吧：

• m (Model ) : Model 層包含著具體的數(shù)據(jù)請(qǐng)求贯卦，數(shù)據(jù)源资柔。
• V (View ) : Activity 和Fragment 視為View層，負(fù)責(zé)處理 UI撵割。
• P (Presenter ) : Presenter 為業(yè)務(wù)處理層贿堰，既能調(diào)用UI邏輯，又能請(qǐng)求數(shù)據(jù)啡彬，該層為純Java類羹与，不涉及任何Android API。

M層是處理數(shù)據(jù)請(qǐng)求的外遇，放到后期再說(shuō)注簿，今天先整理一下V契吉、P兩層跳仿。
如下圖：

整理mvp基類目錄

根據(jù)UI層常用的方法抽出對(duì)應(yīng)的接口，封裝成BaseView捐晶，代碼如下：

/**
 * 類描述：給頁(yè)面基類提供的共用接口
 */
public interface BaseView {
    /**
     * 獲取上下文
     *
     * @return 上下文
     */
    Context getContext();

    /**
     * Show loading
     */
    void showLoading();

    /**
     * hide loading
     */
    void hideLoading();

    /**
     * 顯示提示
     *
     * @param msg
     */
    void showToast(String msg);

    /**
     * 輸出打印
     *
     * @param msg 打印內(nèi)容
     */
    void log(String msg);

}

Presenter業(yè)務(wù)層要與view層進(jìn)行交互菲语，所以需要持有view層的對(duì)象，持有view對(duì)象就有可能出現(xiàn)內(nèi)存泄漏或者空指針問(wèn)題惑灵，所以在抽BasePresenter時(shí)山上，進(jìn)行對(duì)view對(duì)象做對(duì)應(yīng)的處理，因?yàn)関iew層可能是activity英支，也可能是fragment佩憾，所以此處用到了類的泛型，代碼如下：

public class BasePresenter<T extends BaseView> {
    /**
     * 綁定的view
     */
    protected T mView;

    /**
     * 綁定view，一般在初始化中調(diào)用該方法
     */
    public void attachView(T view) {
        this.mView = view;
    }

    /**
     * 斷開view妄帘，一般在onDestroy中調(diào)用
     */
    public void detachView() {
        mView = null;
    }

    /**
     * 獲取連接的view
     */
    public T getView() {
        return mView;
    }

    /**
     * 是否與View建立連接
     * 每次調(diào)用業(yè)務(wù)請(qǐng)求的時(shí)候都要出先調(diào)用方法檢查是否與View建立連接
     */
    public boolean isViewAttached() {
        return mView != null;
    }

}

到這就已經(jīng)抽好了view和Presenter層的基類了楞黄，為了方便管理業(yè)務(wù)層與UI的交互，咱們得能使其相互通信抡驼，否則業(yè)務(wù)層怎么知道UI層的需求和狀態(tài)呢鬼廓，此時(shí)就用一個(gè)契約類來(lái)進(jìn)行管理，此契約類中是抽出的Presenter與view交互的接口(使用時(shí)致盟，可以根據(jù)自己的UI需求碎税，進(jìn)行相應(yīng)的添加接口)，即發(fā)出指令和指令回應(yīng)馏锡，代碼如下：

/**
 * 類描述：管理Presenter與Activity交互的view的接口
 * Presenter 與 View 的契約（交互）
 * 注明：可以添加各個(gè)業(yè)務(wù)對(duì)應(yīng)view與Presenter交互接口
 */
public interface PresenterViewContract {
    //通過(guò)以下接口把與UI層相關(guān)的數(shù)據(jù)通知給UI層
    interface View extends BaseView {
        //接口成功
        void onResultSucceed(String msg);

        //接口失斃柞濉（此處包括接口異常）
        void onResultFail(int retCode, Exception exception);
    
    }

    interface Presenter {
        //接到UI的指令，進(jìn)行處理數(shù)據(jù)
        void getData_1(String keyword);
    }
}

下面咱們就進(jìn)行對(duì)業(yè)務(wù)(Presenter)層實(shí)現(xiàn)杯道，直接上代碼啦

/**
 * 類描述：MVP模式的P模式萎河，用于V和M的數(shù)據(jù)交互使用
 * 修改備注：
 */
public class DataPresenter extends BasePresenter<PresenterViewContract.View> implements PresenterViewContract.Presenter {

    /**
     * 關(guān)閉數(shù)據(jù)加載進(jìn)度提示
     */
    private void cancelDialog() {
        if (isViewAttached()) {
            getView().hideLoading();
        }
    }

    /**
     * 展示數(shù)據(jù)加載進(jìn)度
     */
    private void showDialog() {
        if (isViewAttached()) {
            getView().showLoading();
        }
    }


    /**
     * 接到UI層的指令，發(fā)起數(shù)據(jù)請(qǐng)求
     * @param msg 假數(shù)據(jù)蕉饼，msg為空代表返回失敗結(jié)果虐杯；msg不為空返回成功結(jié)果
     */
    @Override
    public void getData_1(String msg) {
        // TODO: 2020/9/15  此處接口調(diào)用屬于Model層，因?yàn)楣疽延凶约旱囊惶讛?shù)據(jù)包處理昧港，所以此處就用假數(shù)據(jù)代替了
        if (isViewAttached()) {//判斷是否關(guān)聯(lián)View
            if (TextUtils.isEmpty(msg)) {
                cancelDialog();
                //通知view層數(shù)據(jù)請(qǐng)求失敗
                getView().onResultFail(-2, null);
            } else {
                showDialog();
                //通知View層數(shù)據(jù)請(qǐng)求成功
                getView().onResultSucceed(msg);
            }

        }
    }
}

到這view和Presenter的契約就簽好了擎椰，那咱們就開始對(duì)activity和fragment的基礎(chǔ)類進(jìn)攻，它們需要去實(shí)現(xiàn)抽好的BaseView基類的接口（不一定都實(shí)現(xiàn)创肥，用到那個(gè)就實(shí)現(xiàn)那個(gè)）达舒，代碼如下：

/**
 * 類描述：Activity的基類
 * 修改備注：
 */
public class BaseActivity extends AppCompatActivity implements BaseView {
    private String TAG = "";
    private Toast toast;
    private BaseFragment currentFragment = null;//（全局）
    //Loading框的對(duì)象
    private ProgressWaitDialog skyProgressWaitDialog;
    //mvp模式的p對(duì)象
    private DataPresenter dataPresenter = null;

    public DataPresenter getDataPresenter() {
        if (dataPresenter == null) {//初始化P，用于綁定view
            dataPresenter = new DataPresenter();
        }
        return dataPresenter;
    }


    @Override
    public void showLoading() {//展示全局的接口加載進(jìn)度提示
        if (skyProgressWaitDialog == null) {
            skyProgressWaitDialog = new ProgressWaitDialog(this);
        }
        skyProgressWaitDialog.show();
    }

    @Override
    public void hideLoading() {//關(guān)閉提示
        if (skyProgressWaitDialog != null) {
            skyProgressWaitDialog.cancel();
        }
    }


    @Override
    public void showToast(String msg) {
        if (toast == null) {
            // 創(chuàng)建土司
            toast = new Toast(this);
            // 設(shè)置土司顯示的時(shí)間長(zhǎng)短
            toast.setDuration(Toast.LENGTH_LONG);
            // 創(chuàng)建ImageView
            ImageView img = new ImageView(this);
            // 設(shè)置圖片的資源路徑
            img.setImageResource(R.mipmap.ic_launcher);
            // 設(shè)置土司的視圖圖片
            toast.setView(img);
//            toast.setGravity(Gravity.FILL_HORIZONTAL | Gravity.TOP, 0, 0);
            toast.setGravity(Gravity.CENTER, 0, 0);
        }
        // 顯示土司
        toast.show();


        /********************/
//        // 自定義土司顯示位置
//        // 創(chuàng)建土司
//        Toast toast = new Toast(this);
//        // 找到toast布局的位置
//        View layout = View.inflate(this, R.layout.toast, null);
//        // 設(shè)置toast文本叹侄，把設(shè)置好的布局傳進(jìn)來(lái)
//        toast.setView(layout);
//        // 設(shè)置土司顯示在屏幕的位置
//        toast.setGravity(Gravity.FILL_HORIZONTAL | Gravity.TOP, 0, 70);
//        // 顯示土司
//        toast.show();

    }

    public void setTag(String tag) {
        this.TAG = tag;
    }

    @Override
    public void log(String msg) {
        Log.i(TAG, " \n----------------------- \n " + msg + "\n----------------------- \n");
    }

    @Override
    public Context getContext() {
        return this;
    }
    
    //處理Fragment相互切換的方法
    public FragmentTransaction switchFragment(int layoutId, BaseFragment targetFragment) {
        FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
        if (!targetFragment.isAdded()) {
            //第一次使用switchFragment()時(shí)currentFragment為null巩搏，所以要判斷一下
            if (currentFragment != null) {
                transaction.hide(currentFragment);
            }
            transaction.add(layoutId, targetFragment, targetFragment.getClass().getName());
        } else {
            transaction.hide(currentFragment).show(targetFragment);
        }
        currentFragment = targetFragment;
        return transaction;
    }

}

BaseFragment實(shí)現(xiàn)BaseView接口如下：

public class BaseFragment extends Fragment implements BaseView {
    //mvp模式的p對(duì)象
    private DataPresenter dataPresenter = null;

    public DataPresenter getDataPresenter() {
        if (dataPresenter == null) {
            dataPresenter = new DataPresenter();
        }
        return dataPresenter;
    }

    @Override
    public void showLoading() {
    }

    @Override
    public void hideLoading() {

    }

    @Override
    public void showToast(String msg) {
        Toast.makeText(getActivity(),msg,Toast.LENGTH_LONG).show();
    }

    @Override
    public void log(String msg) {
        Log.i("TGH-MainActivity", " \n----------------------- \n " + msg + "\n----------------------- \n");
    }
}

到這里，兩個(gè)View的基礎(chǔ)類實(shí)現(xiàn)完畢了趾代。接下來(lái)咱么寫個(gè)幾個(gè)按鈕進(jìn)行測(cè)試一下以上的封裝是否好用贯底，代碼如下：
MainActivity代碼

public class MainActivity extends BaseActivity implements PresenterViewContract.View {
    private int addFragment = 0;
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout_main_activity);
        setTag("TGH-MainActivity");
        getDataPresenter().attachView(this);
        initView();
        switchFragment(getLayoutId(), Fragment1.getInstance("name", "小小話")).commit();
    }

    private void initView() {
        findViewById(R.id.button_1).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                getDataPresenter().getData_1("測(cè)試接口調(diào)用");
            }
        });
        findViewById(R.id.button_2).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                getDataPresenter().getData_1("");
            }
        });
        findViewById(R.id.button_3).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                addFragment++;
                if (addFragment == 0) {
                    switchFragment(getLayoutId(), Fragment1.getInstance()).commit();
                } else if (addFragment == 1) {
                    switchFragment(getLayoutId(), Fragment2.getInstance()).commit();
                } else if (addFragment == 2) {
                    switchFragment(getLayoutId(), Fragment3.getInstance()).commit();
                    addFragment = -1;
                }
            }
        });
    }

    @Override
    public void onResultSucceed(String msg) {
        showToast("");
        log(msg);
    }

    @Override
    public void onResultFail(int retCode, Exception exception) {
        showToast("onResultFail :" + retCode);
        log("onResultFail :" + retCode);
    }


    /**
     * fragment的容器
     */
    private int getLayoutId() {
        return R.id.fragment_layout;
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        log("main Activity onDestroy");
        getDataPresenter().detachView();
    }
}

MainActivity對(duì)應(yīng)的xml如下：

<?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:orientation="vertical">

    <Button
        android:id="@+id/button_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="成功" />

    <Button
        android:id="@+id/button_2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:text="失敗" />

    <Button
        android:id="@+id/button_3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:text="切換" />

    <RelativeLayout
        android:id="@+id/fragment_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@color/colorAccent" />


</LinearLayout>

Fragment1代碼如下:

public class Fragment1 extends BaseFragment implements PresenterViewContract.View {

    private static Fragment1 fragment1 = null;
    private static String mKey = "";

    public static BaseFragment getInstance(String key, String msg) {
        Log.i("TGH-MainActivity", "Fragment1 進(jìn)行接參數(shù)處理      " + key + "     " + msg);
        getInstance();
        mKey = key;
        Bundle bundle = new Bundle();
        bundle.putString(key, msg);
        getInstance().setArguments(bundle);
        return getInstance();
    }

    public static BaseFragment getInstance() {
        if (fragment1 == null) {
            fragment1 = new Fragment1();
        }
        return fragment1;
    }

    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.layout_fragment, container, false);
        TextView viewById = view.findViewById(R.id.text_view);
        viewById.setText("Fragment1");
        viewById.setTextColor(Color.WHITE);
        log("Fragment1 初始化    " + arguments(mKey));
        getDataPresenter().attachView(this);
        getDataPresenter().getData_1("頁(yè)面卡片 1");
        return view;
    }

    private String arguments(String mKey) {
        Bundle arguments = getArguments();
        if (arguments != null) {
            return arguments.getString(mKey);
        }
        return null;
    }

    @Override
    public void onHiddenChanged(boolean hidden) {
        super.onHiddenChanged(hidden);
        if (hidden) {//隱藏時(shí)，可以清空數(shù)據(jù)
            showToast("Fragment1 隱藏");
        } else {
            log("Fragment1 展示    " + arguments(mKey));
            showToast("Fragment1 展示");
            getDataPresenter().getData_1("");
        }
    }

    @Override
    public void onResultSucceed(String msg) {
        log("卡片 1 中 數(shù)據(jù)成功");
    }

    @Override
    public void onResultFail(int retCode, Exception exception) {
        log("卡片 1 中 數(shù)據(jù)失敗");
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        log("onDestroy");
        getDataPresenter().detachView();
    }
}

Fragment1使用的xml如下撒强，F(xiàn)ragment2和Fragment3同樣使用此xml

<?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:gravity="center"
    android:orientation="vertical">

    <TextView
        android:id="@+id/text_view"
        android:layout_width="match_parent"
        android:gravity="center"
        android:layout_height="wrap_content" />

</LinearLayout>

Fragment2代碼如下：

public class Fragment2 extends BaseFragment implements PresenterViewContract.View {
    private static Fragment2 fragment2 = null;

    public static BaseFragment getInstance() {
        if (fragment2 == null) {
            fragment2 = new Fragment2();
        }
        return fragment2;
    }

    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.layout_fragment, container, false);
        TextView viewById = view.findViewById(R.id.text_view);
        viewById.setText("Fragment2");
        viewById.setTextColor(Color.RED);
        log("Fragment2 初始化");
        getDataPresenter().attachView(this);
        getDataPresenter().getData_1("頁(yè)面卡 2");
        return view;
    }

    @Override
    public void onHiddenChanged(boolean hidden) {
        super.onHiddenChanged(hidden);
        if (hidden) {
            showToast("Fragment2 隱藏");
        } else {
            showToast("Fragment2 展示");
            log("Fragment2 展示");
        }
    }

    @Override
    public void onResultSucceed(String msg) {
        log("頁(yè)面卡 2 成功");
    }

    @Override
    public void onResultFail(int retCode, Exception exception) {
        log("頁(yè)面卡 2 失敗");
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        getDataPresenter().detachView();
    }
}

Fragment3代碼如下：

public class Fragment3 extends BaseFragment {

    private static Fragment3 fragment3 = null;

    public static BaseFragment getInstance() {
        if (fragment3 == null) {
            fragment3 = new Fragment3();
        }
        return fragment3;
    }

    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.layout_fragment, container,false);
        TextView viewById = view.findViewById(R.id.text_view);
        viewById.setText("Fragment3");
        viewById.setTextColor(Color.YELLOW);
        log("Fragment3 初始化");
        return view;
    }


    @Override
    public void onHiddenChanged(boolean hidden) {
        super.onHiddenChanged(hidden);
        if (hidden) {
            showToast("Fragment3 隱藏");
        } else {//用于刷新數(shù)據(jù)
            showToast("Fragment3 展示");
            log("Fragment3 展示");
        }
    }
}

全局提示框代碼也很簡(jiǎn)單禽捆，ProgressWaitDialog代碼如下：

/**
 * 類描述：Loading的工具類
 * 修改備注：
 */

public class ProgressWaitDialog extends ProgressDialog {
    private Context mContext;

    public ProgressWaitDialog(Context context) {
        super(context, R.style.dialog_fullscreen);
        mContext = context.getApplicationContext();
        setCancelable(false);
    }

    @Override
    public void show() {
        if (mContext instanceof Activity && ((Activity) mContext).isFinishing()) {
            return;
        }
        super.show();
        setContentView(R.layout.progress_wait_dialog);
        ImageView img = findViewById(R.id.progress_wait_dialog_image);
        img.setAnimation(AnimationUtils.loadAnimation(mContext, R.anim.loading_animation));
        setCancelable(true);
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        cancel();
        return super.onKeyDown(keyCode, event);
    }

    @Override
    public void cancel() {
        super.cancel();
        dismiss();
    }

    @Override
    public void hide() {
        super.hide();
        dismiss();
    }
}

style中dialog_fullscreen的配置為:

    <style name="dialog_fullscreen" parent="Theme.AppCompat.Dialog">
        <item name="android:windowNoTitle">true</item>
        <item name="android:windowBackground">@android:color/transparent</item>
        <item name="android:windowFrame">@null</item>
        <item name="android:backgroundDimEnabled">true</item>
        <item name="android:windowIsFloating">true</item>
        <item name="android:windowContentOverlay">@null</item>
        <item name="android:windowAnimationStyle">@android:style/Animation.Dialog</item>
        <item name="android:windowSoftInputMode">stateUnspecified|adjustPan</item>
    </style>

以下是R.layout.progress_wait_dialog文件

<?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:id="@+id/dialog_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:minWidth="180dp"
    android:minHeight="60dp"
    android:orientation="vertical"
    android:padding="10dp">

    <ImageView
        android:id="@+id/progress_wait_dialog_image"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@mipmap/progress_wait_icon" />

    <TextView
        android:id="@+id/progress_wait_dialog_txt"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/please_wait"
        android:textColor="@android:color/white"
        tools:text="請(qǐng)稍候..." />
</LinearLayout>  

R.anim.loading_animation文件放在res下的anim下，如下

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:shareInterpolator="false">
    <rotate
        android:duration="1000"
        android:fromDegrees="0"
        android:interpolator="@android:anim/linear_interpolator"
        android:pivotX="50%"
        android:pivotY="50%"
        android:repeatCount="-1"
        android:repeatMode="restart"
        android:startOffset="-1"
        android:toDegrees="+360" />
</set>

好飘哨，今天就到這了