在上篇文章Android性能優化第(八)篇—App啓動速度優化之耗時檢測處理說了應用啓動的攔路虎在哪裏,最後給出了優化思路,如果經過第一輪的優化之後,還是不滿意的話,一般我們是做個啓動頁,因爲啓動頁一般View的數量比較少,業務邏輯比較簡單,啓動就不太費勁。
一、設計思路
- 常規啓動頁設計思路
通常點擊桌面就會執行,Application中的邏輯,這部分的邏輯優化技巧在上篇介紹過,然後會跳入啓動頁SplashActivity,通常展示一個圖片和logo,然後2或3秒後,並且SplashActivity裏面可以去做一些MainActivity的數據的預加載,然後需要通過意圖傳到MainActivity。
優點:啓動速度有所加快
缺點:最終還是要進入首頁,在進入首頁的時候,首頁複雜的View渲染以及必須在UI線程執行的業務邏輯,仍然拖慢了啓動速度。啓動頁簡單執行快,首頁複雜執行慢,前輕後重。
期待:能否在啓動頁的展示的同時,首頁的View就能夠被加載,首頁的業務邏輯就能夠被執行?
- 優化的啓動頁的設計思路
爲了在展示啓動頁的同時,也能渲染首頁,把SplashActivity改成SplashFragment,應用程序的入口仍然是MainActivity,在MainActivity中先展示SplashFragment,當SplashFragment顯示完畢後再將它remove,同時在SplashFragment的2S的友好時間內進行網絡數據緩存,在窗口加載完畢後,我們加載activity_main的佈局,考慮到這個佈局有可能比較複雜,耽誤View的解析時間,採用ViewStub的形式進行懶加載。這樣一開始只要加載SplashFragment所展示的佈局就Ok了。
二、實現
MainActivity .java
public class MainActivity extends FragmentActivity {
private MyHandler mHandler=new MyHandler(this);
public static final String TAG="MainActivity";
private ProgressBar mNetLoadingBar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.d(TAG,"onCreate");
setContentView(R.layout.activity_main);
final SplashFragment splashFragment = new SplashFragment();
final ViewStub mainLayout = (ViewStub) findViewById(R.id.content_viewstub);
//1、一上來首先顯示啓動頁面
FragmentManager supportFragmentManager = getSupportFragmentManager();
if (supportFragmentManager != null) {
FragmentTransaction fragmentTransaction = supportFragmentManager.beginTransaction();
if (fragmentTransaction != null) {
fragmentTransaction.replace(R.id.container, splashFragment);
fragmentTransaction.commit();
}
}
//2、如果主頁有網絡等耗時操作,可以現在就開始
new Thread(new Runnable() {
@Override
public void run() {
//耗時3500
SystemClock.sleep(3000);
mHandler.sendEmptyMessage(0);
}
}).start();
//3、渲染完畢後,立刻加載主頁佈局
getWindow().getDecorView().post(new Runnable() {
@Override
public void run() {
Log.d(TAG," getWindow().getDecorView().post");
View mainView = mainLayout.inflate();
initView(mainView);
}
});
//4、 啓動頁有動畫,延遲一下,播放完動畫,執行remove
getWindow().getDecorView().post(new Runnable() {
@Override
public void run() {
mHandler.postDelayed(new DelayRunnableImpl(MainActivity.this, splashFragment), 2000);
}
});
}
@Override
protected void onResume() {
super.onResume();
Log.d(TAG,"onResume");
}
/**
* 初始化主頁View
*/
private void initView(View pMainView) {
if (pMainView != null) {
mNetLoadingBar = (ProgressBar) pMainView.findViewById(R.id.progressbar);
mNetLoadingBar.setVisibility(View.VISIBLE);
}
}
private static class MyHandler extends Handler {
private WeakReference<MainActivity> wRef;
private MyHandler(MainActivity pActivity) {
this.wRef = new WeakReference<MainActivity>(pActivity);
}
@Override
public void handleMessage(Message msg) {
MainActivity mainActivity = wRef.get();
if (mainActivity != null) {
mainActivity.mNetLoadingBar.setVisibility(View.GONE);
}
}
}
private class DelayRunnableImpl implements Runnable {
WeakReference<Context> contextWref;
WeakReference<Fragment> fragmentWref;
private DelayRunnableImpl(Context pContext, Fragment pFragment) {
this.contextWref = new WeakReference<>(pContext);
this.fragmentWref = new WeakReference<>(pFragment);
}
@Override
public void run() {
FragmentActivity context = (FragmentActivity) contextWref.get();
if (context != null) {
FragmentManager supportFragmentManager = context.getSupportFragmentManager();
if (supportFragmentManager != null) {
FragmentTransaction fragmentTransaction = supportFragmentManager.beginTransaction();
SplashFragment fragment = (SplashFragment) fragmentWref.get();
if (fragment != null) {
fragmentTransaction.remove(fragment);
fragmentTransaction.commit();
}
}
}
}
}
@Override
protected void onDestroy() {
super.onDestroy();
if (mHandler != null) {
mHandler.removeCallbacksAndMessages(null);
}
}
}
SplashFragment .java
public class SplashFragment extends Fragment {
public SplashFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View ret = inflater.inflate(R.layout.fragment_splash, container, false);
initView(ret);
return ret;
}
private void initView(View ret) {
if (ret != null) {
ImageView imageView = (ImageView) ret.findViewById(R.id.laucher_logo);
playAnimator(imageView);
}
}
private void playAnimator(ImageView pView) {
if (pView != null) {
PropertyValuesHolder pvhA = PropertyValuesHolder.ofFloat("alpha", 1f, 0.7f, 0.1f);
// PropertyValuesHolder pvhR= PropertyValuesHolder.ofFloat("rotationX", 0.0F, 360.0F);
ObjectAnimator.ofPropertyValuesHolder(pView, pvhA).setDuration(2000).start();
}
}
}
activity_mian.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="zhangwan.wj.com.myshare.activity.MainActivity">
<ViewStub
android:id="@+id/content_viewstub"
android:layout="@layout/main_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<FrameLayout
android:id="@+id/container"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RelativeLayout>
fragment.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="zhangwan.wj.com.myshare.fragment.SplashFragment">
<ImageView
android:id="@+id/laucher_logo"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/launch" />
</FrameLayout>
main_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/migu_home"
android:contentDescription="@string/app_name" />
<ProgressBar
android:id="@+id/progressbar"
android:indeterminateDrawable="@drawable/progress_bar"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="center" />
</FrameLayout>
效果怎麼樣呢?
看一下啓動時間
C:\Users\wangjing>adb shell am start -W zhangwan.wj.com.myshare/zhangwan.wj.com.myshare.activity.MainActivity
Starting: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] cmp=zhangwan.wj.com.myshare/.activity.MainActivity }
Status: ok
Activity: zhangwan.wj.com.myshare/.activity.MainActivity
ThisTime: 683
TotalTime: 683
Complete
還是挺不錯的吧。
Please accept mybest wishes for your happiness and success !