Android Window、PhoneWindow、Activity学习心得第二弹 Window 分析
这里先给出部分源码
目录（Android 4.4/frameworks/base/core/java/android/view/Window.java）
public abstract class Window {public static final int FEATURE_OPTIONS_PANEL = 0;public static final int FEATURE_NO_TITLE = 1;…….public static final int FEATURE_CONTEXT_MENU = 6;public static final int FEATURE_CUSTOM_TITLE = 7;public static final int FEATURE_ACTION_BAR = 8;public static final int FEATURE_ACTION_BAR_OVERLAY = 9;…….public interface Callback {…..public boolean dispatchKeyEvent(KeyEvent event);……public boolean dispatchTouchEvent(MotionEvent event);…..public boolean dispatchGenericMotionEvent(MotionEvent event);….public View onCreatePanelView(int featureId);….public boolean onMenuItemSelected(int featureId, MenuItem item);…..public void onWindowAttributesChanged(WindowManager.LayoutParams attrs);public void onContentChanged();public void onWindowFocusChanged(boolean hasFocus);public void onAttachedToWindow();public void onDetachedFromWindow();public void onPanelClosed(int featureId, Menu menu);public boolean onSearchRequested();public ActionMode onWindowStartingActionMode(ActionMode.Callback callback);public void onActionModeStarted(ActionMode mode);public void onActionModeFinished(ActionMode mode);}public void setCallback(Callback callback) {mCallback = callback;}public void setFlags(int flags, int mask) {final WindowManager.LayoutParams attrs = getAttributes();attrs.flags = (attrs.flags&~mask) | (flags&mask);if ((mask&WindowManager.LayoutParams.FLAG_NEEDS_MENU_KEY) != 0) {attrs.privateFlags |= WindowManager.LayoutParams.PRIVATE_FLAG_SET_NEEDS_MENU_KEY;}mForcedWindowFlags |= mask;if (mCallback != null) {mCallback.onWindowAttributesChanged(attrs);}}public boolean requestFeature(int featureId) {final int flag = 1<<featureId;mFeatures |= flag;mLocalFeatures |= mContainer != null ? (flag&~mContainer.mFeatures) : flag;return (mFeatures&flag) != 0;}public View findViewById(int id) {return getDecorView().findViewById(id);}public abstract void setContentView(int layoutResID);public abstract void setTitle(CharSequence title);public abstract LayoutInflater getLayoutInflater();}首先，正如我们所知道的通过回调的方式Activity implements Window.Callback
而Callback主要用来处理
按键事件（dispatchKeyEvent）
触摸事件 （dispatchTouchEvent） 滑动事件（dispatchTrackballEvent）等等一系列事件
设置菜单、ActionMOde、监控内容等一系列动作
正是因为
mWindow = PolicyManager.makeNewWindow(this);mWindow.setCallback(this);监听回调，所以一系列最终的处理交给了Activity
当然，这里对于处理不做具体分析
接下来，我们看看
Window属性 FEATURE_OPTIONS_PANEL = 0; 功能不明，参见后面的说明(默认使能) FEATURE_NO_TITLE = 1; 无标题栏 FEATURE_PROGRESS = 2; 在标题栏上显示加载进度，例如webview加载网页时(条状进度条) FEATURE_LEFT_ICON = 3; 在标题栏左侧显示一个图标 FEATURE_RIGHT_ICON = 4; 在标题栏右侧显示一个图标 FEATURE_INDETERMINATE_PROGRESS = 5; 不确定的进度(圆圈状等待图标) FEATURE_CONTEXT_MENU = 6; 上下文菜单，相当于PC上的右键菜单(默认使能) FEATURE_CUSTOM_TITLE = 7; 自定义标题栏，该属性不能与其他标题栏属性合用 FEATURE_OPENGL = 8; 如果开启OpenGL，那么2D将由OpenGL处理(OpenGL中2D是3D的子集) PROGRESS_VISIBILITY_ON = -1; 进度条可见 PROGRESS_VISIBILITY_OFF = -2; 进度条不可见 PROGRESS_INDETERMINATE_ON = -3; 开启不确定模式 PROGRESS_INDETERMINATE_OFF = -4; 关闭不确定模式 PROGRESS_START = 0; 第一进度条的最小值 PROGRESS_END = 10000; 第一进度条的最大值 PROGRESS_SECONDARY_START = 20000; 第二进度条的最小值 PROGRESS_SECONDARY_END = 30000; 第二进度条的最大值
这些 Feature 和 Flag 有什么用呢,其实很明显他们决定了我们Activity外貌（风格和样式）
那么，接下来我们就来看看Window的具体实现类PhoneWindow
目录（Android 4.4/frameworks/base/policy/src/com/android/internal/policy/impl/PhoneWindow.java）
成功是奋斗的结果，而奋斗是成功的必经之路。
