小编Geo*_*Shg的帖子

我需要能够复制Qwidget,因此我可以复制一个窗口,因为它会在运行时更改.这可能吗？

void Duplicate(QWidget * Show)
{
 //I tried...
 Qwidget Shw = *Show; //but operator= is private
 //and the copy constructor (I think), which is also private
 Qwidget Shw(*Show);
 //

 Shw.Show();
}

我将android SDK解压缩到一个名为"/ usr/android/android-sdk-linux"的文件夹中.我进入"工具/"并双击可执行文件"android",单击"在终端中运行"但没有任何反应.我也点击"运行",但没有任何反应.我在终端(./android命令)中运行它,我得到:

./android: 1: ./android: java: not found
./android: 1: ./android: java: not found
./android: 110: exec: java: not found

那为什么会这样呢？

编辑:以下是结果~$ java

* default-jre
* gcj-4.6-jre-headless
* openjdk-6-jre-headless
* gcj-4.5-jre-headless
* openjdk-7-jre-headless

我试过这个:

int editlength;
int buttonid = 3324; // id to button, the numbers dont mean anything
int editid = 5652; // id to edit

LPTSTR  edittxt;

HWND button; // created in wWinmain as a button
HWND edit; // created in wWinMain as an edit control

// LRESULT CALLBACK WindowProc

switch(uMsg)
{
    case WM_COMMAND:
        if(wParam == buttonid)
        {
            filedit = GetDlgItem(hwnd, editid); // I tried with and without this
            editlength = GetWindowTextLength(filedit);
            GetWindowText(filedit, edittxt, editlength);

            MessageBox(hwnd, edittxt, L"edit text", 0);
        } …

如何在单击按钮时在运行时调整全局hwnd变量的大小？

或者只是在运行时调整窗口大小的任何方法.即

HWND hwnd; //global
int buttonid = 250; // an id for a button
//also global


int WINAPI wWinMain(/*blah blah blah */) {


//blah blah blah

hwnd = CreateWindowEx(
    0,
    L"WindowClass",
    L"Window",
    WS_OVERLAPPEDWINDOW,
    CW_USEDEFAULT, CW_USEDEFAULT,
    300, 275,
    NULL,
    NULL,
    hInstance,
    NULL
    );

    HWND mybutton = CreateWindow(
    L"BUTTON",
    L"Button",
    WS_VISIBLE | WS_CHILD | WS_TABSTOP,
    14, 13,
    250, 200,
    hwnd,
    (HMENU)buttonid,
    hInstance,
    NULL
    );

//blah blah blah

}


LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lparam) {

switch(uMsg) { …

我想画一个滑块的背景.我尝试了这个,但颜色覆盖了整个滑块.这是一个继承的QSlider类

void paintEvent(QPaintEvent *e) {
  QPainter painter(this);
  painter.begin(this);
  painter.setBrush(/*not important*/);

  // This covers up the control. How do I make it so the color is in
  // the background and the control is still visible?
  painter.drawRect(rect()); 

  painter.end();
}

在大多数编码程序中,您可以右键单击该项目并单击"在资源管理器中显示",它会在资源管理器中显示所选项目的文件.你会怎么用QDesktopServices在Qt中做到这一点？(或在QT中的任何方式)

你如何用GDI绘制透明椭圆？我试过SetBkMode()但我仍然得到一个白色的椭圆形bk.

case WM_PAINT:
{
    hdc = BeginPaint(hwnd, &ps);
    SetBkMode(hdc, TRANSPARENT); // doesnt work
    Ellipse(hdc, 0,0,500,500);
    EndPaint(hwnd, &ps);
    break;
}

为什么插槽Reset()不起作用？我希望按钮"reset"将sider的值重置为零.

class MySlider : public QSlider
{
   public:
    MySlider(Qt::Orientation orientation, QWidget *parent = 0) : QSlider(orientation parent){}

   public slots:
   void Reset()
   {
   this->setValue(0);
   }
};

//it doesnt work when i try this

MySlider * Slider = new MySlider(Qt::Horizontal, this);

QPushButton *Reset = new QPushButton(tr("Reset"), this);

connect(Reset, SIGNAL(clicked()), Slider, SLOT(Reset()) );

QtreeWidget顶部有一个1.我如何解决它？

这有效......

QToolButton * toolbutton = new QToolButton(this);

//hide before addWidget
toolbutton->hide();

addWidget(toolbutton);

但事实并非如此

QToolButton * toolbutton = new QToolButton(this)

addWidget(toolbutton);

//hide after addWidget
toolbutton->hide();

有没有替代方案,所以我可以在QToolButton添加到QToolBar后实际隐藏？我需要在运行时.

这是一个非常基本的运算符过载问题.说我有这样的课......

class xy
{
    public:
    double x, y;
    XY(double X, double Y) { x = X; y = Y;}
    XY operator+(const XY & add) const {
        return XY(this->x + add.x, this->y + add.y);
    }
    XY & operator+=(const XY & add) const {?}
    }
}

我希望operator + = do做它应该做的事情(你知道,添加到x和y的当前值).运算符+和运算符+ =的代码不一样吗？

我在这个程序中使用BitBlt时遇到了麻烦.您调整窗口大小,椭圆随之调整大小.当然,使用普通的hdc方法,它是波涛汹涌的.我尝试了BitBlt方法,但这也不起作用(可能是因为我做错了).有人可以解决我的错误吗？感谢名单

    bool sizing; //global   
case WM_PAINT:
    {
        RECT rect;
        GetClientRect(hwnd, &rect);
        hdc = BeginPaint(hwnd, &ps);
        mem = CreateCompatibleDC(hdc);
        SelectObject(mem, GetStockObject(HOLLOW_BRUSH));
        if(sizing)
        {
        Ellipse(mem,rect.left, rect.top, rect.right, rect.bottom);
        }
    BitBlt(hdc, rect.left, rect.top, rect.left - rect.right, rect.top -rect.bottom , mem, rect.left, rect.top, SRCCOPY);
        DeleteDC(mem);
        EndPaint(hwnd, &ps);
        break;
    }
    case WM_SIZE:
        sizing = true;
        break;

我在xna游戏的update()部分有这个:

            while (TouchPanel.IsGestureAvailable)
        {
            GestureSample gs = TouchPanel.ReadGesture();

            switch (gs.GestureType)
            {
                case GestureType.Flick:
                    _GameMap.GameCamera.Translate(new Vector2(-gs.Delta.X/2, 0));
                    //moves the camera by this amount 
                    break;
            }
        }

但不出所料,当我轻弹没有滚动(如谷歌地球或愤怒的小鸟),它只是一个开始和结束.如何在轻弹中实现滚动？