tiled crash when trying to select an object in warn/error callback from issues view #4189

Hmm, this isn't crashing Tiled on my system (Linux) either on latest master or using the 1.11.2 release. Rather it's doing exactly what it's supposed to do (though I hadn't really expect push to work).

It seems rather unlikely that this issue would depend on the operating system. Maybe it depends on the Qt version? Are you using the 32-bit of 64-bit version of Tiled?

Could you try whether it also crashes when you just do this instead:

obj.map.selectedObjects = [obj];

The installer I used was called Tiled-1.11.2_Windows-10+_x86_64.msi

The code I provided I think is doing the same, e.g. making a new array and then pushing to it, I've tried a few variants. The centerOn method works great and it moves to the position.

Is there perhaps something wrong with the object i'm putting into the list? Is it because I need to select the layer first via code? the obj in question should be a MapObject (Polygon or Rectangle), and the toolbar for selecting an object requires me to be on the object layer first.

I'll see if I can make a smaller reproduce in another test project

I've created a reproduce repository here https://drive.google.com/drive/folders/14GUFRjK77p1ep700L9dVvCyCOVgDETly?usp=sharing since I can not attach it as a 7zip file.

• enable project extension when it asks
• press ctrl + e to export the map with the Map Exporter
• press ok to the alert
• tiled now crashes

The following code snippet is the extension in the extensions folder next to the project in case I remove the drive link at some point

function createErrorCallback(obj = undefined) {
    return () => {
        tiled.alert("tiled is crashing now");
        if (obj) {
            // First select the object
            // TODO: Figure out how to do this, my attempts  to do this crashes tiled
            obj.map.selectedObjects = [];
            obj.map.selectedObjects.push(obj);
            // obj.layer.selected = true;
            // obj.selected = true;

            // Then center the view on it
            tiled.mapEditor.currentMapView.centerOn(obj.x + obj.width / 2, obj.y + obj.height / 2);
        }
    };
}

// Register the format
const mapDataFormat = {
    name: "Map Exporter",
    extension: "json",
    write: function (map, fileName) {
        tiled.log("Processing " + map.layerCount + " layers...");
        for (let i = 0; i < map.layerCount; ++i) {
            const layer = map.layerAt(i);
            for (let i = 0; i < layer.objectCount; ++i) {
                const obj = layer.objectAt(i);

                tiled.error(`Object ${obj.name} error, double click to select`, createErrorCallback(obj));
            }
        }

        return ""; // When a non-empty string is returned, it is shown as error message.
    },
};

tiled.registerMapFormat("mapData", mapDataFormat);
tiled.log("MapData format registered successfully!");

I have just used obj.map.selectedObjects = [obj] in an ordinary tiled extension, and it works here on the callback. I think perhaps the crash is related to the fact that the error callback comes from a registerMapFormat method?