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我未曾珍惜的,我不在拥有

二:binder驱动情景分析—数据结构

2024-09-08

android

binder

server端在binder中提供的服务会以一个binder_node的结构存储在binder驱动中。

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四:APP与surfaceflinger服务连接过程

2024-08-15

android

显示

viewrootimpl内部会创建一个空的surface，还未被赋值

public final Surface mSurface = new Surface();

程序执行完requestlayout之后最终会调用到session.addTodisplay,最终执行到wms@addWindow

public int addWindow(Session session, IWindow client, int seq,
            WindowManager.LayoutParams attrs, int viewVisibility, int displayId,
            Rect outContentInsets, InputChannel outInputChannel) {
            win = new WindowState(this, session, client, token,
                    attachedWindow, appOp[0], seq, attrs, viewVisibility, displayContent);
            win.attach();
        return res;
    }

   WindowState@attach 
   void attach() {
        if (WindowManagerService.localLOGV) Slog.v(
            WindowManagerService.TAG, "Attaching " + this + " token=" + mToken
            + ", list=" + mToken.windows);
        mSession.windowAddedLocked();
    } 
    
    Session@windowAddedLocked
    void windowAddedLocked() {
        if (mSurfaceSession == null) {
            mSurfaceSession = new SurfaceSession();
            mService.mSessions.add(this);
        }
        mNumWindow++;

windowAddedLocked中创建了SurfaceSession对象。surfacesession的创建会调用nativeCreate进行jni调用

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三:view绘制

2024-08-09

android

显示

viewrootimpl@performTraversals

当decorview创建完成后，解析xml布局。最终就到了requestlayout开始计算布局的宽高位置以及绘制。

viewrootimpl@performTraversals

   private void performTraversals() {
		   //获取decorview的宽高规格
        WindowManager.LayoutParams lp = mWindowAttributes;
        //顶层视图decorview所需要的宽高
        int desiredWindowWidth;
        int desiredWindowHeight;
        //此时mFirst = true
        if (mFirst) {
            mFullRedrawNeeded = true;
            mLayoutRequested = true;
            //如果窗口类型是有状态栏的,则顶层视图的窗口宽度和高度就是除了状态栏
            if (shouldUseDisplaySize(lp)) {
                Point size = new Point();
                mDisplay.getRealSize(size);
                desiredWindowWidth = size.x;
                desiredWindowHeight = size.y;
            } } else {
		            //如果没有则decorview的宽高就是整个屏幕的宽高
                desiredWindowWidth = mWinFrame.width();
                desiredWindowHeight = mWinFrame.height();
            }
              int childWidthMeasureSpec = getRootMeasureSpec(mWidth, lp.width);
              int childHeightMeasureSpec = getRootMeasureSpec(mHeight, lp.height);
              ...
               // Ask host how big it wants to be
               //执行测量操作
              performMeasure(childWidthMeasureSpec, childHeightMeasureSpec);
              ...
              //执行设置位置操作
              performLayout(lp, mWidth, mHeight);
              ...
              //绘制操作
              performDraw();
    }

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xml自定义布局加载

2024-08-08

android

显示
- Activity@setContentView:
Activity@setContentView:

这个getWindow就是phonewindow，它是在activity的attach方法中被初始化的。

最终调用phonewindow中的setcontentView方法。 mLayoutInflater.inflate(layoutResID,mContentParent)对布局资源进行加载
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二:decorview加载

2024-08-06

android

显示

当系统调用启动一个activity是就会通过反射启动,然后调用handlelauncheractivity。在handlelauncheracitiviy中执行mInstrumentation.callActivityOnCreate调用activity的oncrreate，并且调用activity.attach函数创建窗口视图phonewindow。

 private Activity performLaunchActivity(ActivityClientRecord r, Intent customIntent) {
        ActivityInfo aInfo = r.activityInfo;
                activity.attach(activityBaseContext, this, getInstrumentation(), r.token,
                        r.ident, app, r.intent, r.activityInfo, title, r.parent,
                        r.embeddedID, r.lastNonConfigurationInstances, config,
                        r.referrer, r.voiceInteractor, window, r.activityConfigCallback,
                        r.assistToken, r.shareableActivityToken, r.initialCallerInfoAccessToken);
                r.activity = activity;
                if (r.isPersistable()) {
                    mInstrumentation.callActivityOnCreate(activity, r.state, r.persistentState);
                } else {
                    mInstrumentation.callActivityOnCreate(activity, r.state);
                }
            }
            r.setState(ON_CREATE);
       
        return activity;
    }

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七:binder的C++实现注册服务

2024-08-06

android

binder

int main(int argc __unused, char** argv)
{
    ...
    InitializeIcuOrDie();
    //获得ProcessState实例对象【见小节2.1】
    sp<ProcessState> proc(ProcessState::self());
    //获取BpServiceManager对象
    sp<IServiceManager> sm = defaultServiceManager();
    AudioFlinger::instantiate();
    //注册多媒体服务  【见小节3.1】
    MediaPlayerService::instantiate();
    ResourceManagerService::instantiate();
    CameraService::instantiate();
    AudioPolicyService::instantiate();
    SoundTriggerHwService::instantiate();
    RadioService::instantiate();
    registerExtensions();
    //启动Binder线程池
    ProcessState::self()->startThreadPool();
    //当前线程加入到线程池
    IPCThreadState::self()->joinThreadPool();
 }

1.打开驱动ProcessState::self()

2.通过defaultServiceManager获取sm对象。

3.开启线程池不断获取客户端发送的数据

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一:图形window加载视图

2024-08-01

android

显示

window的初始化

window的初始化

activity加载视图,就相当于是一个容器一样。activitythread中启动activity时调用attach

 private Activity performLaunchActivity(ActivityClientRecord r, Intent customIntent) {
	 activity.attach(appContext, this, getInstrumentation(), r.token,
                          r.ident, app, r.intent, r.activityInfo, title, r.parent,
                         r.embeddedID, r.lastNonConfigurationInstances, config,
                          r.referrer, r.voiceInteractor, window, r.configCallback,                          r.assistToken);
 }
 
 final void attach(Context context, ActivityThread aThread,...) {
		  mWindow = new PhoneWindow(this, window, activityConfigCallback);
		  mWindow.setCallback(this);
		  mWindow.setWindowManager(
                (WindowManager)context.getSystemService(Context.WINDOW_SERVICE),
                mToken, mComponent.flattenToString(),
                (info.flags & ActivityInfo.FLAG_HARDWARE_ACCELERATED) != 0);
      mWindowManager = mWindow.getWindowManager();
 }

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九:binder框架framework分析

2024-07-23

android

binder

注册服务过程

framework binder就是将bpbinder转换为binderproxy使用。

注册服务过程

servicemanager.java

public static void addService(String name, IBinder service, boolean allowIsolated) {
    try {
        //先获取SMP对象，则执行注册服务操作【见小节3.2/3.4】
        getIServiceManager().addService(name, service, allowIsolated);
    } catch (RemoteException e) {
        Log.e(TAG, "error in addService", e);
    }
}

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十:匿名binder

2024-07-08

android

binder

匿名binder是要依托于实名binder而存在的。当服务端通过实名binder向客户端传输一个匿名binder，客户端端会接收到一个匿名binder的引用然后可以向位于匿名binder进程发送数据。在内核层匿名binder通过实名binder发送给驱动后，驱动会检查当前的flat_binder_obj是否在当前进程有binder_node。

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一:图形硬件(Gralloc,Hardware Composer)

2024-07-02

android

显示
- gralloc
硬件抽象层统一了硬件调用的接口。

gralloc

图形缓冲，用于保存图形的一段内存。图形缓冲运行在一个独立的进程.由它负责分配图形缓冲。是一个独立的进程。gralloc对应的接口类
```
interface IAllocator {
	allocate(BufferDescriptor descriptor, uint32_t count)
    generates (Error error,
               uint32_t stride,
               vec<handle> buffers);
};
```
其中BufferDescriptor描述了申请的buffer的宽高格式等信息。count表示申请的缓冲区的个数。 IAllocator 的具体实现在pasthrough.cpp
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Welcome to joshuayingwhat's Blog!

viewrootimpl@performTraversals

Activity@setContentView:

window的初始化

注册服务过程

gralloc