使用 firefox 插件将 firefox window 置于最前面

Question

我想在我的 firefox addon 上使用特定功能 运行 时关注 firefox。我创建了一个 .vbs 文件，它可以关注 firefox[置于顶部] 然后我使用 nsIProcess.like this

执行该 exe

file.initWithPath("C:\Users\madhawax\Documents\focusFirefox.vbs");
var process = Cc["@mozilla.org/process/util;1"].createInstance(Ci.nsIProcess);
process.init(file);
process.run(false, args, args.length);

它可以工作 fine.but 现在出于某种原因，我想直接从插件代码中聚焦 Firefox，而不需要另一个应用程序的帮助。我读过 firefox windows api 但我还是找不到焦点 window.what 我想问的是如何从插件代码中焦点浏览器。

编辑..

这是我用来关注 firefox 的代码。

focusFirefox.vbs

Set wshShell = CreateObject("WScript.Shell")
wshShell.AppActivate("Firefox")

Answer 1

这些解决方案使用 js-ctypes winapi。这是一个 Windows 解决方案。 OSX 和 Linux 没有这个问题，那里很容易窃取焦点。

如果我们只做SetForegroundWindowwinapi方法就容易了，但是调用这个方法的进程必须有用户焦点。如果没有，那么它什么都不做，所以这里是强制它的方法：

附加到线程方法（推荐方法）

此方法执行以下操作：

1. 获取当前在前台的window
2. 如果 none 找到，常规 SetForegroundWindow 将起作用，所以它会这样做并退出
3. 如果window在前台找到它然后获取其线程的ID
4. 然后将其与当前 firefox 的线程 ID（目标 windows 线程）进行比较
5. 如果相同则使用常规 SetForegroundWindow 并退出
6. 如果不相同，则使用 AttachThreadInput 将 firefox 的线程附加到当前前台的线程 window
7. 如果第 6 步调用失败，则放弃并退出该函数，并抛出错误
8. 如果第 6 步中的调用没有失败，那么它将调用 SetForegroundWindow，因为它现在可以工作了
9. 然后它会撤消在第 6 步中完成的附件，因此如果您现在进行 SetForegroundWindow 调用，它将像往常一样失败

我想不出 AttachThreadInput 会失败的原因，但如果失败了，那是此方法唯一不万无一失的部分。如果有人知道为什么会失败，请针对该失败原因分享解决方案。但是，我将下面的 SetCursorPos 方法留作紧急备用。

Cu.import('resource://gre/modules/Services.jsm');
Cu.import('resource://gre/modules/ctypes.jsm');

if (ctypes.voidptr_t.size == 4 /* 32-bit */ ) {
    var is64bit = false;
} else if (ctypes.voidptr_t.size == 8 /* 64-bit */ ) {
    var is64bit = true;
} else {
    throw new Error('huh??? not 32 or 64 bit?!?!');
}

var user32 = ctypes.open('user32.dll');

var GetForegroundWindow = user32.declare('GetForegroundWindow', ctypes.winapi_abi,
    ctypes.voidptr_t // return
);

var DWORD = ctypes.uint32_t;
var LPDWORD = DWORD.ptr;

var GetWindowThreadProcessId = user32.declare('GetWindowThreadProcessId', ctypes.winapi_abi,
    DWORD, // return
    ctypes.voidptr_t, // hWnd
    LPDWORD // lpdwProcessId
);

var AttachThreadInput = user32.declare('AttachThreadInput', ctypes.winapi_abi,
    ctypes.bool, // return
    DWORD, // idAttach
    DWORD, // idAttachTo
    ctypes.bool // fAttach
);

var SetForegroundWindow = user32.declare('SetForegroundWindow', ctypes.winapi_abi,
    ctypes.bool, // return BOOL
    ctypes.voidptr_t // HWND
);

function forceFocus() {

    var hToDOMWindow = Services.wm.getMostRecentWindow('navigator:browser');
    if (!hToDOMWindow) {
        throw new Error('No browser window found');
    }

    var hToBaseWindow = hToDOMWindow.QueryInterface(Ci.nsIInterfaceRequestor)
        .getInterface(Ci.nsIWebNavigation)
        .QueryInterface(Ci.nsIDocShellTreeItem)
        .treeOwner
        .QueryInterface(Ci.nsIInterfaceRequestor)
        .getInterface(Ci.nsIBaseWindow);

    var hToString = hToBaseWindow.nativeHandle;
    var hTo = ctypes.voidptr_t(ctypes.UInt64(hToString));


    var hFrom = GetForegroundWindow();
    if (hFrom.isNull()) {
        var rez_SetSetForegroundWindow = SetForegroundWindow(hTo);
        console.log('rez_SetSetForegroundWindow:', rez_SetSetForegroundWindow);
        return true;
    }

    if (hTo.toString() == hFrom.toString()) {
        console.log('window is already focused');
        return true;
    }

    var pid = GetWindowThreadProcessId(hFrom, null);
    console.info('pid:', pid);

    var _threadid = GetWindowThreadProcessId(hTo, null); // _threadid is thread of my firefox id, and hTo is that of my firefox id so this is possible to do
    console.info('_threadid:', _threadid);

    if (pid == _threadid) {
        var rez_SetSetForegroundWindow = SetForegroundWindow(hTo);
        console.log('rez_SetSetForegroundWindow:', rez_SetSetForegroundWindow);
        return true;
    }

    var rez_AttachThreadInput = AttachThreadInput(_threadid, pid, true)
    console.info('rez_AttachThreadInput:', rez_AttachThreadInput);
    if (!rez_AttachThreadInput) {
        throw new Error('failed to attach thread input');
    }
    var rez_SetSetForegroundWindow = SetForegroundWindow(hTo);
    console.log('rez_SetSetForegroundWindow:', rez_SetSetForegroundWindow);

    var rez_AttachThreadInput = AttachThreadInput(_threadid, pid, false)
    console.info('rez_AttachThreadInput:', rez_AttachThreadInput);
}

setTimeout(function() {
    forceFocus();
    user32.close();
}, 5000);

窃取然后恢复光标位置的方法（不推荐的方法 - 不是万无一失的，因为它模拟点击 - 如果用户在全屏模式下 window，它可能会点击类似 link 的东西，并且link 位于 window)

的位置 0,0

这是一个使用 js-ctypes 且仅适用于 Windows 操作系统的解决方案，它执行以下操作：

1. 将目标 window 设置为 "always on top"（但焦点尚未在 window 中）
2. 获取当前光标位置
3. 将光标位置设置到 window
的左上角
4. 点击以聚焦
5. 将光标位置恢复到原来的位置
6. 将 window 设置回正常（不是 "always on top"）

它有一个问题，即 SendInput 中合成鼠标点击的 x 和 y 坐标没有得到尊重，这就是为什么我不得不使用 SetCursorPos，在未来的修订中我想解决这个问题，这样它就不会使用 SetCursorPos，因为移动用户的鼠标对用户来说很烦人，但好处远远超过轻微的烦恼，因为给予 window 焦点非常重要，我是暂时接受这个SetCursorPos方法，因为我做了一个"restore cursor position to before stealing"，所以这里是：

Cu.import('resource://gre/modules/Services.jsm');
Cu.import('resource://gre/modules/ctypes.jsm');

function myFocus() {

    //////// START Ctypes DECLARES

    if (ctypes.voidptr_t.size == 4 /* 32-bit */ ) {
        var is64bit = false;
    } else if (ctypes.voidptr_t.size == 8 /* 64-bit */ ) {
        var is64bit = true;
    } else {
        throw new Error('huh??? not 32 or 64 bit?!?!');
    }

    var user32 = ctypes.open('user32.dll');

    var SetWindowPos = user32.declare('SetWindowPos', ctypes.winapi_abi,
        ctypes.bool, //return
        ctypes.voidptr_t, //hwnd
        ctypes.voidptr_t, //hWndInsertAfter
        ctypes.int, //X
        ctypes.int, //Y
        ctypes.int, //cx
        ctypes.int, //cy
        ctypes.unsigned_int //uFlags
    );

    var RECT = ctypes.StructType('_RECT', [
        {left: ctypes.long},
        {top: ctypes.long},
        {right: ctypes.long},
        {bottom: ctypes.long}
    ]);
    var LPRECT = RECT.ptr;
    var GetWindowRect = user32.declare('GetWindowRect', ctypes.winapi_abi,
        ctypes.bool, // return
        ctypes.voidptr_t, // hwnd
        LPRECT // lpRect
    );

    var SetCursorPos = user32.declare('SetCursorPos', ctypes.winapi_abi,
        ctypes.bool, // return
        ctypes.int, // x
        ctypes.int // y
    );

    var POINT = ctypes.StructType('_tagPoint', [
        {x: ctypes.long},
        {y: ctypes.long}
    ]);
    var LPPOINT = POINT.ptr;

    var GetCursorPos = user32.declare('GetCursorPos', ctypes.winapi_abi,
        ctypes.bool, // return
        LPPOINT // lpPoint
    );

    // send mouse stuff
    var ULONG_PTR = is64bit ? ctypes.uint64_t : ctypes.unsigned_long;
    var DWORD = ctypes.uint32_t;
    var MOUSEINPUT = ctypes.StructType('tagMOUSEINPUT', [
        {'dx': ctypes.long},
        {'dy': ctypes.long},
        {'mouseData': DWORD},
        {'dwFlags': DWORD},
        {'time': ULONG_PTR},
        {'dwExtraInfo': DWORD}
    ]);

    var INPUT = ctypes.StructType('tagINPUT', [
        {'type': DWORD},
        {'mi': MOUSEINPUT} // union, pick which one you want, we want keyboard input
    ]);
    var LPINPUT = INPUT.ptr;

    var SendInput = user32.declare('SendInput', ctypes.winapi_abi, ctypes.unsigned_int, ctypes.unsigned_int, LPINPUT, ctypes.int);

    var INPUT_MOUSE = 0;
    var MOUSEEVENTF_LEFTDOWN = 2;
    var MOUSEEVENTF_LEFTUP = 4;
    var MOUSEEVENTF_ABSOLUTE = 0x8000;
    // end send mouse stuff

    var HWND_TOP = ctypes.voidptr_t(-1); //ctypes.cast(ctypes.int(-1), ctypes.voidptr_t);
    var HWND_NOTOPMOST = ctypes.voidptr_t(-2);
    var SWP_NOMOVE = 2;
    var SWP_NOSIZE = 1;

    //////// END Ctypes DECLARES


    // pick a one of our navigator:browser firefox windows to focus
    var browserWindow = Services.wm.getMostRecentWindow('navigator:browser');
    if (!browserWindow) {
        throw new Error('No browser window found');
    }

    // convert our DOMWindow to a HWND
    var baseWindow = browserWindow.QueryInterface(Ci.nsIInterfaceRequestor)
        .getInterface(Ci.nsIWebNavigation)
        .QueryInterface(Ci.nsIDocShellTreeItem)
        .treeOwner
        .QueryInterface(Ci.nsIInterfaceRequestor)
        .getInterface(Ci.nsIBaseWindow);
    var hwndString = baseWindow.nativeHandle;
    var hwnd = ctypes.voidptr_t(ctypes.UInt64(hwndString));


    browserWindow.focus(); // this is important, withou this, i dont know why, but the window will not become "always on top" from the SetWindowPos code on the next line
    var rez_SetWindowPos = SetWindowPos(hwnd, HWND_TOP, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE);
    console.log('rez_SetWindowPos:', rez_SetWindowPos);

    var myRect = RECT();
    var rez_GetWindowRect = GetWindowRect(hwnd, myRect.address());
    console.log('rez_SetWindowPos:', rez_SetWindowPos);

    var myRectLeft = parseInt(myRect.left.toString());
    var myRectTop = parseInt(myRect.top.toString());
    console.log('myRect.left', myRectLeft);
    console.log('myRect.top', myRectTop);

    var myPoint = POINT();
    var rez_GetCursorPos = GetCursorPos(myPoint.address());
    console.log('rez_GetCursorPos:', rez_GetCursorPos);
    var myPointX = parseInt(myPoint.x.toString());
    var myPointY = parseInt(myPoint.y.toString());
    console.log('myPoint.x', myPointX);
    console.log('myPoint.y', myPointY);

    var rez_SetCursorPos = SetCursorPos(myRect.left, myRect.top);
    console.log('rez_SetWindowPos:', rez_SetWindowPos);

    // may need to wait for the window to come to top
    // send click - i dont know why but the x and y coords of these send clicks is not being respected, it is just clicking where the mouse is, so im having to use SetCursorPos as temp hack
    var js_pInputs = [
        INPUT(INPUT_MOUSE, MOUSEINPUT(myRectLeft, myRectTop, 0, MOUSEEVENTF_LEFTDOWN | MOUSEEVENTF_ABSOLUTE, 0, 0)),
        INPUT(INPUT_MOUSE, MOUSEINPUT(myRectLeft, myRectTop, 0, MOUSEEVENTF_LEFTUP | MOUSEEVENTF_ABSOLUTE, 0, 0))
    ];

    var pInputs = INPUT.array()(js_pInputs);

    var rez_SI = SendInput(pInputs.length, pInputs, INPUT.size);
    console.log('rez_SI:', rez_SI.toString());
    // end send click

    var rez_SetCursorPos = SetCursorPos(myPoint.x, myPoint.y);
    console.log('rez_SetWindowPos:', rez_SetWindowPos);

    var rez_SetWindowPos = SetWindowPos(hwnd, HWND_NOTOPMOST, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE);
    console.log('rez_SetWindowPos:', rez_SetWindowPos);

    user32.close();

}
setTimeout(function() {
    myFocus();
}, 5000);

这是需要的方法，因为如果调用它的进程不是当前聚焦的进程，SetForegroundWindow什么都不做。

经过测试，即使将另一个 window 设置为 "always on top" 也能正常工作，但因为另一个 window 始终位于顶部，所以在聚焦此 window.