final void attach(Context context, ActivityThread aThread,
		Instrumentation instr, IBinder token, int ident,
		Application application, Intent intent, ActivityInfo info,
		CharSequence title, Activity parent, String id,
		NonConfigurationInstances lastNonConfigurationInstances,
		Configuration config, String referrer, IVoiceInteractor voiceInteractor,
		Window window, ActivityConfigCallback activityConfigCallback) {
	attachBaseContext(context);
	...
	mWindow = new PhoneWindow(this, window, activityConfigCallback);//1
	...
	mWindow.setWindowManager(
			(WindowManager)context.getSystemService(Context.WINDOW_SERVICE),
			mToken, mComponent.flattenToString(),
			(info.flags & ActivityInfo.FLAG_HARDWARE_ACCELERATED) != 0);//2
}

public class PhoneWindow extends Window {
	public PhoneWindow(Context context, Window preservedWindow,
            ActivityConfigCallback activityConfigCallback) {
		//這里最終會(huì)調(diào)父類Window的構(gòu)造方法，并傳入Activity的實(shí)例context。
        this(context);
        //只有Activity的Window才會(huì)使用Decor context,其他依賴使用的Context
        mUseDecorContext = true;
        ...
   }
}

public Window(Context context) {
	mContext = context;
	mFeatures = mLocalFeatures = getDefaultFeatures(context);
}

public void setWindowManager(WindowManager wm, IBinder appToken, String appName,
		boolean hardwareAccelerated) {
	//如果wm是空，則創(chuàng)建一個(gè)WindowManager服務(wù)：注釋1
	if (wm == null) {
		wm = (WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE);
	}
	//注釋2
	mWindowManager = ((WindowManagerImpl)wm).createLocalWindowManager(this);
}

@Override
public Object getSystemService(String name) {
	return SystemServiceRegistry.getSystemService(this, name);
}
進(jìn)入SystemServiceRegistry的getSystemService方法，name = Context.WINDOW_SERVICE
public static Object getSystemService(ContextImpl ctx, String name) {
	ServiceFetcher<?> fetcher = SYSTEM_SERVICE_FETCHERS.get(name);//1
	return fetcher != null ? fetcher.getService(ctx) : null;//2
}

static {
	...
	registerService(Context.WINDOW_SERVICE, WindowManager.class,
		new CachedServiceFetcher<WindowManager>() {
	@Override
	public WindowManager createService(ContextImpl ctx) {
		return new WindowManagerImpl(ctx);
	}});
}

private static <T> void registerService(String serviceName, Class<T> serviceClass,
            ServiceFetcher<T> serviceFetcher) 

public WindowManagerImpl createLocalWindowManager(Window parentWindow) {
	return new WindowManagerImpl(mContext, parentWindow);
}

public void setContentView(@LayoutRes int layoutResID) {
	getWindow().setContentView(layoutResID);//1
	initWindowDecorActionBar();//2
}

public void setContentView(int layoutResID) {
	...
	if (mContentParent == null) {
		installDecor();//注釋1
	} 
	mLayoutInflater.inflate(layoutResID, mContentParent);//注釋2
	...
}
private void installDecor() {
	...
	if (mDecor == null) {
		mDecor = generateDecor(-1);
	} else {
		mDecor.setWindow(this);
	}
}
protected DecorView generateDecor(int featureId) {
	...
	return new DecorView(context, featureId, this, getAttributes());
}

private void initWindowDecorActionBar() {
	Window window = getWindow();
	// Initializing the window decor can change window feature flags.
	// Make sure that we have the correct set before performing the test below.
	window.getDecorView();
	if (isChild() || !window.hasFeature(Window.FEATURE_ACTION_BAR) || mActionBar != null) {
		return;
	}
	mActionBar = new WindowDecorActionBar(this);
	mActionBar.setDefaultDisplayHomeAsUpEnabled(mEnableDefaultActionBarUp);
	...
}

//1.設(shè)置主題
public void setTheme(int resid) {
    super.setTheme(resid);
    mWindow.setTheme(resid);
}
//2.設(shè)置Window屬性等
public final boolean requestWindowFeature(int featureId) {
    return getWindow().requestFeature(featureId);
}
//3.獲取Layout解析器
public LayoutInflater getLayoutInflater() {
    return getWindow().getLayoutInflater();
}

public static class LayoutParams extends ViewGroup.LayoutParams implements Parcelable {
	//應(yīng)用程序窗口的起始值
	public static final int FIRST_APPLICATION_WINDOW = 1;
	//應(yīng)用程序窗口的基準(zhǔn)值
    public static final int TYPE_BASE_APPLICATION   = 1;
	//標(biāo)準(zhǔn)的應(yīng)用程序窗口：依附于Activity存在
	public static final int TYPE_APPLICATION        = 2;
	public static final int TYPE_APPLICATION_STARTING = 3;
	public static final int TYPE_DRAWN_APPLICATION = 4;
	//應(yīng)用程序窗口結(jié)束值
	public static final int LAST_APPLICATION_WINDOW = 99;
	...
}

public static class LayoutParams extends ViewGroup.LayoutParams implements Parcelable {
	public static final int FIRST_SUB_WINDOW = 1000;//子窗口類型初始值
	public static final int TYPE_APPLICATION_PANEL = FIRST_SUB_WINDOW;
	public static final int TYPE_APPLICATION_MEDIA = FIRST_SUB_WINDOW + 1;
	public static final int TYPE_APPLICATION_SUB_PANEL = FIRST_SUB_WINDOW + 2;
	public static final int TYPE_APPLICATION_ATTACHED_DIALOG = FIRST_SUB_WINDOW + 3;
	public static final int TYPE_APPLICATION_MEDIA_OVERLAY  = FIRST_SUB_WINDOW + 4; 
	public static final int TYPE_APPLICATION_ABOVE_SUB_PANEL = FIRST_SUB_WINDOW + 5;
	public static final int LAST_SUB_WINDOW = 1999;//子窗口類型結(jié)束值
	...
}

public static class LayoutParams extends ViewGroup.LayoutParams implements Parcelable {
	public static final int FIRST_SYSTEM_WINDOW     = 2000;//系統(tǒng)窗口類型初始值
	public static final int TYPE_STATUS_BAR         = FIRST_SYSTEM_WINDOW;//系統(tǒng)狀態(tài)欄窗口
	public static final int TYPE_SEARCH_BAR         = FIRST_SYSTEM_WINDOW+1;//搜索條窗口
	public static final int TYPE_PHONE              = FIRST_SYSTEM_WINDOW+2;//通話窗口
	public static final int TYPE_SYSTEM_ALERT       = FIRST_SYSTEM_WINDOW+3;//系統(tǒng)ALERT窗口
	public static final int TYPE_KEYGUARD           = FIRST_SYSTEM_WINDOW+4;//鎖屏窗口
	public static final int TYPE_TOAST              = FIRST_SYSTEM_WINDOW+5;//TOAST窗口
	...
	public static final int LAST_SYSTEM_WINDOW      = 2999;//系統(tǒng)窗口類型結(jié)束值
}

Window mWindow =getWindow(); 
mWindow.addFlags(LayoutParams.FLAG_KEEP_SCREEN_ON);

mWindow.setFlags(LayoutParams.FLAG_KEEP_SCREEN_ON,LayoutParams.FLAG_KEEP_SCREEN_ON);

WindowManager.LayoutParams wl = new WindowManager.LayoutParams();
wl.flags = LayoutParams.FLAG_KEEP_SCREEN_ON;
Log.d("TAG","window:"+window.getWindowManager());
WindowManager mWindowManager = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
TextView mTextView=new TextView(this);
mTextView.setText("ttttttttdddddd");
Log.d("TAG","mWindow:"+mWindowManager);
mWindowManager.addView(mTextView,wl);

public interface ViewManager{
	public void addView(View view, ViewGroup.LayoutParams params);
    public void updateViewLayout(View view, ViewGroup.LayoutParams params);
    public void removeView(View view);
}

public final class WindowManagerImpl implements WindowManager{
	private final WindowManagerGlobal mGlobal = WindowManagerGlobal.getInstance();
    @Override
    public void addView(@NonNull View view, @NonNull ViewGroup.LayoutParams params) {
        applyDefaultToken(params);
        mGlobal.addView(view, params, mContext.getDisplay(), mParentWindow);
    }
    @Override
    public void updateViewLayout(@NonNull View view, @NonNull ViewGroup.LayoutParams params) {
        applyDefaultToken(params);
        mGlobal.updateViewLayout(view, params);
    }	
    @Override
    public void removeView(View view) {
        mGlobal.removeView(view, false);
    }
	...
}

public void addView(View view, ViewGroup.LayoutParams params,
		Display display, Window parentWindow) {
	...
	ViewRootImpl root;
	//將params強(qiáng)轉(zhuǎn)為WindowManager.LayoutParams類型
	final WindowManager.LayoutParams wparams = (WindowManager.LayoutParams) params;
	synchronized (mLock) {
		//創(chuàng)建一個(gè)ViewRootImpl對(duì)象
		root = new ViewRootImpl(view.getContext(), display);
		//給View設(shè)置LayoutParams參數(shù)
		view.setLayoutParams(wparams);
		//存儲(chǔ)view到mViews列表
		mViews.add(view);
		//存儲(chǔ)root到mRoots列表
		mRoots.add(root);
		//存儲(chǔ)wparams到mParams列表
		mParams.add(wparams);
		// do this last because it fires off messages to start doing things
		try {
			root.setView(view, wparams, panelParentView);
		} catch (RuntimeException e) {
			// BadTokenException or InvalidDisplayException, clean up.
			if (index >= 0) {
				removeViewLocked(index, true);
			}
			throw e;
		}
	}
}

public void setView(View view, WindowManager.LayoutParams attrs, View panelParentView) {
	...
	requestLayout();//注釋1
	...
	res = mWindowSession.addToDisplay(mWindow, mSeq, mWindowAttributes,
                            getHostVisibility(), mDisplay.getDisplayId(),
                            mAttachInfo.mContentInsets, mAttachInfo.mStableInsets,
                            mAttachInfo.mOutsets, mInputChannel);//注釋2
	...
}

mWindowSession = WindowManagerGlobal.getWindowSession();
public static IWindowSession getWindowSession() {
    synchronized (WindowManagerGlobal.class) {
        if (sWindowSession == null) {
            try {
                InputMethodManager imm = InputMethodManager.getInstance();
                IWindowManager windowManager = getWindowManagerService();//1
                sWindowSession = windowManager.openSession(//2
                        new IWindowSessionCallback.Stub() {
                                @Override
                                public void onAnimatorScaleChanged(float scale) {
                                        ValueAnimator.setDurationScale(scale);
                                }
                        },
                        imm.getClient(), imm.getInputContext());
            } catch (RemoteException e) {
                throw e.rethrowFromSystemServer();
            }
        }
        return sWindowSession;
    }
}

@Override
public IWindowSession openSession(IWindowSessionCallback callback, IInputMethodClient client,
		IInputContext inputContext) {
	if (client == null) throw new IllegalArgumentException("null client");
	if (inputContext == null) throw new IllegalArgumentException("null inputContext");
	Session session = new Session(this, callback, client, inputContext);
	return session;
}

public int addToDisplay(IWindow window, int seq, WindowManager.LayoutParams attrs,
		int viewVisibility, int displayId, Rect outContentInsets, Rect outStableInsets,
		Rect outOutsets, InputChannel outInputChannel) {
	return mService.addWindow(this, window, seq, attrs, viewVisibility, displayId,
			outContentInsets, outStableInsets, outOutsets, outInputChannel);
}

public void removeView(View view, boolean immediate) {
    ...
    synchronized (mLock) {
        int index = findViewLocked(view, true);//1
        View curView = mRoots.get(index).getView();//2
        removeViewLocked(index, immediate);//3
        if (curView == view) {
                return;
        }
        throw new IllegalStateException("Calling with view " + view
                        + " but the ViewAncestor is attached to " + curView);
    }
}
private int findViewLocked(View view, boolean required) {
    final int index = mViews.indexOf(view);
    if (required && index < 0) {
        throw new IllegalArgumentException("View=" + view + " not attached to window manager");
    }
    return index;
}

private void removeViewLocked(int index, boolean immediate) {
    ...
    boolean deferred = root.die(immediate);
    if (view != null) {
        view.assignParent(null);
        if (deferred) {
                mDyingViews.add(view);
        }
    }
}

boolean die(boolean immediate) {
    ...
    //如果是同步移除，則立即調(diào)用doDie方法
    if (immediate && !mIsInTraversal) {
        doDie();
        return false;
    }
    ...
    //異步移除，發(fā)出一個(gè)msg進(jìn)行移除
    mHandler.sendEmptyMessage(MSG_DIE);
    return true;
}

void doDie() {
    ...
    synchronized (this) {
        if (mAdded) {
                dispatchDetachedFromWindow();//1
        }
        ..
    }
    WindowManagerGlobal.getInstance().doRemoveView(this);//4
}

void dispatchDetachedFromWindow() {
    if (mView != null && mView.mAttachInfo != null) {
        //這里可以看出我們可以在View銷毀前，在View的dispatchDetachedFromWindow做一些資源釋放操作
        mView.dispatchDetachedFromWindow();
    }
    //銷毀硬件渲染線程
    destroyHardwareRenderer();
    //將mView的root置為mull
    mView.assignParent(null);
    mView = null;
    mAttachInfo.mRootView = null;
    //釋放當(dāng)前Surface
    mSurface.release();
    //核心移除View的方法。
    try {
            mWindowSession.remove(mWindow);
    } catch (RemoteException e) {
    }
    //移除同步屏障以及View的繪制task
    unscheduleTraversals();
}

public void remove(IWindow window) {
    mService.removeWindow(this, window);
}

public void removeWindow(Session session, IWindow client) {
    synchronized(mWindowMap) {
        // 得到 windowstate 對(duì)象
        WindowState win = windowForClientLocked(session, client, false);
        if (win == null) {
            return;
        }
        // 進(jìn)行移除 window 操作
        removeWindowLocked(win);
    }
}