void display() const override { std::cout << "ConcreteDerived display" << std::endl; } }; int main() { AbstractBase* b = new ConcreteDerived(); b->display(); // 输出 "ConcreteDerived display" delete b; return 0; } ``` 在这个例子中,`AbstractBase`是一个抽象类,因为它包含一个纯...
* frameworks/base/media/jni/android_media_ImageReader.cpp static const JNINativeMethod gImageReaderMethods[] = { {"nativeClassInit", "()V", (void*)ImageReader_classInit }, {"nativeInit", "(Ljava/lang/Object;IIIIJ)V", (void*)ImageReader_init }, {"nativeClose", "()V", (void*)ImageRe...
根据前面的分析,在创建VirtualDisplay时,会执行到handleDisplayDeviceAddedLocked(),一起看一下该方法:1.handleDisplayDeviceAddedLocked()private void handleDisplayDeviceAddedLocked(DisplayDevice device) { DisplayDeviceInfo info = device.getDisplayDeviceInfoLocked(); ... mDisplayDevices.add(device); LogicalDisp...
#include<iostream>#include<stdlib.h>usingnamespacestd;constdoublepi=3.1415926;classCircle{public:Cir...
(const sp<IBinder>& token,uint32_t layerStack) { Composer::getInstance().setDisplayLayerStack(token, layerStack);}void Composer::setDisplayLayerStack(const sp<IBinder>& token,uint32_t layerStack) { Mutex::Autolock _l(mLock); DisplayState& s(getDisplayStateLocked(token)); s.layerStack = ...
mNeedsDisplayListSync置为true,表示需要向RenderThread同步DisplayList的信息。 具体的DisplayList信息则保存在mStagingDisplayList中。 再回到DrawFrameTask类的成员函数run中,它的执行逻辑如下所示: 1)、创建一个TreeInfo对象,模式为MODE_FULL,暂且记下。 2)、调用成员函数syncFrameState将应用程序窗口的Display List、Re...
垃圾回收具体都是通过调用函数void dvmCollectGarbageInternal(const GcSpec* spec) 来执行垃圾回收,该函数的参数GcSpec结构体定义见本文的附录。对于函数dvmCollectGarbageInternal的内部逻辑,即垃圾回收流程,根据垃圾回收线程和工作线程的关系分为并行GC和非并行GC。前者在回收阶段有选择性的停止当前工作线程,后者在垃圾...
publicconstdoublePI=Math.PI; 8 protecteddoublex, y; 9 publicDimensions() 10 { 11 } 12 publicDimensions(doublex,doubley) 13 { 14 this.x=x; 15 this.y=y; 16 } 17 18 publicvirtualdoubleArea() 19 { 20 returnx*y; 21 } 22
class TestClass { public class Shape { public const double PI = Math.PI; protected double _x, _y; public Shape() { } public Shape(double x, double y) { _x = x; _y = y; } public virtual double Area() { return _x * _y; } } public class Circle : Shape { public Circle(...
classTestClass{publicclassShape{publicconstdoublePI = Math.PI;protecteddouble_x, _y;publicShape(){ }publicShape(doublex,doubley){ _x = x; _y = y; }publicvirtualdoubleArea(){return_x * _y; } }publicclassCircle:Shape{publicCircle(doubler) :base(r,0){ }publicoverridedoubleArea(){return...