如何在IOS 5及以上版本中找到最前端应用的紫色端口？

Question

I am trying to write an app that runs in the background and injects touches to the springboard or other apps. I understand that I will be using private APIs and structures. The app is an enterprise app and does not need to be approved for the AppStore.

I am using the GSEvent structure as suggested by KennyTM with some minor modifications for IOS 5/6. I am able to send touch events and other events to the Springboard by sending GSSystemEvents.

I need to be able to send similar events to other applications as well, but I am not able to find the port for the front most application.

Is there a way to get the port for the application that is upfront and running so that I can send my GSEvents to the app?

It would be nice if someone can point me to examples or show me how I can get the purple port of the front most app.

Thanks!

Answer 1

UPDATE: I haven't tested this on ios7.

I happen to work on the exact same requirement before.

To get the purple port, you can use GSCopyPurpleNamedPort() with the bundle Id as an argument.

If you need to simulate touch on SpringBoard, use GSGetPurpleSystemEventPort.

With this below code, you should be able to get the port and use it to inject touch system wide.

#import <dlfcn.h>
// Framework Paths
#define SBSERVPATH  "/System/Library/PrivateFrameworks/SpringBoardServices.framework/SpringBoardServices"
-(mach_port_t)getFrontMostAppPort
{
    bool locked;
    bool passcode;
    mach_port_t *port;
    void *lib = dlopen(SBSERVPATH, RTLD_LAZY);
    int (*SBSSpringBoardServerPort)() = dlsym(lib, "SBSSpringBoardServerPort");
    void* (*SBGetScreenLockStatus)(mach_port_t* port, bool *lockStatus, bool *passcodeEnabled) = dlsym(lib, "SBGetScreenLockStatus");
    port = (mach_port_t *)SBSSpringBoardServerPort();
    dlclose(lib);
    SBGetScreenLockStatus(port, &locked, &passcode);
    void *(*SBFrontmostApplicationDisplayIdentifier)(mach_port_t *port, char *result) = dlsym(lib, "SBFrontmostApplicationDisplayIdentifier");
    char appId[256];
    memset(appId, 0, sizeof(appId));
    SBFrontmostApplicationDisplayIdentifier(port, appId);
    NSString * frontmostApp=[NSString stringWithFormat:@"%s",appId];
    if([frontmostApp length] == 0 || locked)
        return GSGetPurpleSystemEventPort();
    else
        return GSCopyPurpleNamedPort(appId);
}

I've tested...this works fine on iOS 5 and 6. You might not need the lock part if you don't inject when the lock screen shows up. Hope this helps.