簡述

這篇文章是基於OSCHINA Android客戶端4.1.7版本的分析，之前很多人都分析過原始碼，但是都是幾年前的程式碼分析，隨著時間的推移，開源中國的原始碼也在變化，接下來的一段時間我將分享我通過學習開源中國的程式碼所獲得東西。

啟動頁面

研究一個APP或者一個網站的原始碼，最開始的時候一定會從APP或者網站的入口學習。OSCHINA的入口從下的配置檔案可以找到AndroidManifest.xml

<application
        android:name=".OSCApplication"
        android:allowBackup="false"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/App.Theme.Light"
        tools:replace="android:allowBackup">
        <meta-data
            android:name="android.max_aspect"
            android:value="2.1" />

        <activity
            android:name=".improve.main.splash.SplashActivity"
            android:label="@string/app_name"
            android:screenOrientation="portrait"
            android:theme="@style/App.Theme.Launch">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        ......
        ......
</application>
 

通過可以判斷開源中國的入口檔案就是SplashActivity

類的繼承關係

SplashActivity原始碼

package net.oschina.app.improve.main.splash;

import android.content.Context;
import android.content.Intent;
import android.text.TextUtils;
import android.view.View;
import android.widget.FrameLayout;

import com.baidu.mobstat.SendStrategyEnum;
import com.baidu.mobstat.StatService;

import net.oschina.app.OSCApplication;
import net.oschina.app.R;
import net.oschina.app.Setting;
import net.oschina.app.improve.account.AccountHelper;
import net.oschina.app.improve.app.AppOperator;
import net.oschina.app.improve.base.activities.BaseActivity;
import net.oschina.app.improve.bean.Launcher;
import net.oschina.app.improve.bean.User;
import net.oschina.app.improve.main.MainActivity;
import net.oschina.app.improve.main.introduce.IntroduceActivity;
import net.oschina.app.improve.main.tabs.DynamicTabFragment;
import net.oschina.app.improve.main.update.OSCSharedPreference;
import net.oschina.app.improve.utils.CacheManager;

import java.io.File;

import butterknife.Bind;

/**
 * 啟動頁設計
 * Created by huanghaibin on 2017/11/25.
 */

public class SplashActivity extends BaseActivity {


    @Bind(R.id.frameSplash)
    FrameLayout mFlameSplash;

    @Bind(R.id.fl_content)
    FrameLayout mFlameContent;

    private boolean isShowAd;

    public static void show(Context context) {
        System.out.println("SplashActivity:"+"show()方法");
        context.startActivity(new Intent(context, SplashActivity.class));
    }

    @Override
    protected int getContentView() {
        System.out.println("SplashActivity:"+"getContentView()方法");
        return R.layout.activity_splash;
    }

    @Override
    protected void initWidget() {
        super.initWidget();
    }


    @Override
    protected void initData() {
        super.initData();
        System.out.println("SplashActivity:"+"initData()方法");
        StatService.setSendLogStrategy(this, SendStrategyEnum.APP_START, 1, false);
        StatService.start(this);
        Launcher launcher = CacheManager.readJson(OSCApplication.getInstance(), "Launcher", Launcher.class);
        String savePath = OSCApplication.getInstance().getCacheDir() + "/launcher";
        System.out.println("SplashActivity:"+"launcher方法");
        File file = new File(savePath);
        if (launcher != null && !launcher.isExpired() && file.exists()) {
            System.out.println("SplashActivity:"+"initData()方法");
            isShowAd = true;
            mFlameSplash.setVisibility(View.GONE);
            mFlameContent.setVisibility(View.VISIBLE);
            addFragment(R.id.fl_content, AdFragment.newInstance(launcher));
        }
        AppOperator.runOnThread(new Runnable() {
            @Override
            public void run() {
                doMerge();
            }
        });
    }

    private void doMerge() {
        // 判斷是否是新版本

        if (Setting.checkIsNewVersion(this)) {
            // Cookie遷移
            System.out.println("SplashActivity:"+"doMerge()方法");
            String cookie = OSCApplication.getInstance().getProperty("cookie");
            if (!TextUtils.isEmpty(cookie)) {
                OSCApplication.getInstance().removeProperty("cookie");
                User user = AccountHelper.getUser();
                user.setCookie(cookie);
                AccountHelper.updateUserCache(user);
                OSCApplication.reInit();
            }
        }

        // 欄目相關資料合併操作
        DynamicTabFragment.initTabPickerManager();

        if (isShowAd)
            return;
        // Delay...
        try {
            Thread.sleep(800);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        // 完成後進行跳轉操作
        redirectTo();
    }

    private void redirectTo() {
        System.out.println("SplashActivity:"+"redirectTo() 方法");
        if (OSCSharedPreference.getInstance().isFirstInstall()) {
            IntroduceActivity.show(this);
        } else {
            MainActivity.show(this);
        }
        finish();
    }

    @Override
    public void onBackPressed() {
        //super.onBackPressed();
    }
}

 

一個activity啟動最開始應該是onCreate()方法，這個類中沒有onCreate方法。是因為onCreate方法在抽象類BaseActivity中，基類中寫了onCreate方法，以後的無論什麼類繼承基類就都可以，免去了重複程式碼。