#iOS  #Javascript  #Objective C  #Titanium Mobile

Creating [object] in a different context than the calling function.

On 19 August 2016 in Tech

Creating [object] in a different context than the calling function.

This warning occured when a JS callback function is passed to Objective-C as KrollCallback and then executed on non-JS thread.

KrollCallback *callback = [args [email protected]"callback"];

[OneSignal initWithLaunchOptions:[TiApp app].launchOptions appId:appId handleNotificationAction:^(OSNotificationResult *result) {
    [callback call:@[] thisObject:nil];
}];

Problem with this warning is, if the JS callback create Ti.Network.HTTPClient instance, then that instance is null.

function callback() {
    var http = Ti.Network.createHTTPClient();
    http.open('GET', getUrl()); // JS error! http is null
    http.send();
}

To fix, get krollContext instance of current module/proxy and execute callback inside invokeBlockOnThread

// For TiModule / TiProxy descendants
KrollContext *context = [self.executionContext krollContext];

// For TiUIView descendants
KrollContext *context = [self.proxy.executionContext krollContext];

// invoke
[context invokeBlockOnThread:^{
    [callback call:@[] thisObject:nil];
}];

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