WEBVTT 00:07.090 --> 00:08.080 Welcome back. 00:08.080 --> 00:17.560 Now if we load up our menu here, as you can see I have three slots saved just from playing around entering 00:17.560 --> 00:21.100 in a name no name and saving. 00:21.100 --> 00:28.090 We have these slots saved and as we've seen we can go in and delete any of these from our save games. 00:28.090 --> 00:33.940 I can delete the third one there and it won't show up anymore because it no longer exists. 00:34.300 --> 00:40.510 But as soon as we do enter something in here, now we have a select slot button. 00:40.510 --> 00:41.620 This one's up a little bit. 00:41.620 --> 00:47.620 It's raised because with no text there, well it sort of collapses that text box there. 00:47.620 --> 00:52.390 But either way we have a select slot button which is not implemented. 00:52.390 --> 00:54.940 And we want to be able to select a slot. 00:55.660 --> 01:02.560 Now, what that means is as soon as we have a slot selected, we should remember that somehow, somewhere. 01:02.560 --> 01:07.660 And that should affect what happens if we press our play or delete buttons. 01:07.660 --> 01:11.590 So we need a way to know which slot is selected. 01:11.590 --> 01:18.520 First of all, and as soon as we do select a slot, if any of the other two are selected, we need to 01:18.520 --> 01:19.780 update those as well. 01:19.780 --> 01:22.540 If we select a slot, how are we going to know it's selected? 01:23.020 --> 01:26.500 Well, a good way is to disable the button, right? 01:26.500 --> 01:33.880 So we need a way to first of all disable the button and then respond to knowing which slot is selected. 01:34.210 --> 01:36.460 Now if we go into our widgets. 01:37.630 --> 01:43.750 And UI load menu and take a look at the take in widget. 01:44.710 --> 01:47.920 Our select slot button if we go to the graph. 01:48.460 --> 01:55.750 Has its onClick event and it's calling select slot button pressed, letting the mVVM load screen view 01:55.750 --> 01:58.780 model know which button has been pressed. 01:58.810 --> 02:02.470 Another thing we can do is we can disable the button itself. 02:02.620 --> 02:06.250 We can take our select slot button. 02:07.120 --> 02:11.080 And with its button we can call set is enabled. 02:15.320 --> 02:19.370 And we can set it to not enabled, we can disable the button. 02:19.370 --> 02:23.330 Now all that's going to do is if we click on it, it'll be disabled. 02:23.330 --> 02:25.820 If we click on any of them, they'll all be disabled. 02:25.820 --> 02:33.290 And when that happens, we should probably go and enable all the other buttons if they are disabled 02:33.290 --> 02:33.920 already. 02:33.920 --> 02:37.130 So that very basic task we can handle. 02:37.130 --> 02:44.180 We know that our load screen view model is going to know which button was just selected, and it can 02:44.180 --> 02:47.570 set the others to be enabled. 02:47.960 --> 02:54.170 So how is it going to do that if it doesn't know anything about the actual widget blueprints themselves? 02:54.170 --> 02:58.970 Well, it has a reference to the other view models, the load screen view models. 02:58.970 --> 03:06.170 Those load screen view models are capable of broadcasting data, and we can easily broadcast data up 03:06.170 --> 03:07.520 to their widgets. 03:07.760 --> 03:13.340 For example, if we go to our load slot view model, we've already made a delegate to broadcast the 03:13.340 --> 03:14.870 widget switcher index. 03:14.870 --> 03:21.620 We can make another one to broadcast whether or not to enable the select slot button, right. 03:21.620 --> 03:28.370 So we can make a new delegate called F enable select slot button. 03:29.090 --> 03:34.550 And this can broadcast a boolean and it can be called be enable. 03:34.550 --> 03:38.210 So we can have a blueprint assignable delegate here. 03:39.650 --> 03:43.700 And we can call it enable select slot button. 03:43.910 --> 03:46.190 And it can be of course blueprint assignable. 03:46.190 --> 03:46.580 Right. 03:46.580 --> 03:49.550 And we can broadcast a value for this. 03:49.940 --> 03:54.680 So we need to bind to this in our load slot taken. 03:54.680 --> 03:56.720 And we're going to have to compile to do that. 03:56.720 --> 04:03.080 But before we go about doing that we can also realize that as soon as select slot button pressed is 04:03.080 --> 04:07.430 called, we can then tell those slots to broadcast that delegate. 04:07.910 --> 04:14.480 So here in our load screen ViewModel and select slot button pressed, the first thing we can do is we 04:14.480 --> 04:22.820 can access our load slots, and we can broadcast that delegate with a boolean based on which slot there 04:22.820 --> 04:23.570 is. 04:23.570 --> 04:25.430 So we can loop through those slots. 04:25.430 --> 04:28.850 Here's a loop in load data where we're doing just that. 04:28.850 --> 04:30.380 We can copy that. 04:30.970 --> 04:37.780 And we can have a for loop here where we're looping over each of our load slots, and we can even tell 04:37.810 --> 04:40.540 each of the load slots to broadcast that delegate. 04:40.540 --> 04:44.560 We can take that load slot and we have to get value from it. 04:44.560 --> 04:46.600 That gives us the load slot. 04:47.050 --> 04:54.250 We can access that enable select slot button delegate and we can broadcast. 04:55.030 --> 05:03.340 Now as long as they bind some event to this delegate in those widgets, then they can respond by enabling 05:03.340 --> 05:04.630 or disabling the button. 05:04.630 --> 05:10.120 But if we just selected a button with this slot, the slot that's passed in, we only want to disable 05:10.120 --> 05:11.950 that one and enable the others. 05:11.950 --> 05:17.950 So what we can do is we can check the key here and see if it's equal to that slot. 05:17.950 --> 05:31.420 So we can say if load slot dot key is equal to slot in that case then this is the button that we should 05:31.420 --> 05:32.170 disable. 05:32.170 --> 05:37.300 So really if we go back into blueprint we don't really even have to disable anything here as long as 05:37.300 --> 05:38.530 we bind to a delegate. 05:38.530 --> 05:44.350 Because that delegate can be broadcast and we can respond to it and disable the button there, we can 05:44.350 --> 05:47.200 simply get our load slot dot value. 05:48.620 --> 05:53.420 And broadcast, and we want to disable the button so we can pass false in here. 05:54.090 --> 05:56.040 Now for all the others. 05:56.040 --> 06:00.930 In other words, there's an else case here we can broadcast true to enable those buttons. 06:00.930 --> 06:05.460 So what we'll do is paste this line and change this from false to true. 06:05.460 --> 06:11.370 And now all we need to do is make sure that those widgets bind to enable select slot button. 06:12.650 --> 06:16.280 So we can save all here and close the editor. 06:17.100 --> 06:22.200 And we can compile and relaunch and bind to enable select slot button. 06:22.200 --> 06:23.280 Let's try that. 06:24.830 --> 06:28.850 So back here in the editor, here's our load slot taken. 06:29.270 --> 06:36.770 We can have this widget bind a callback as soon as we know that it has a valid load slot view model. 06:36.800 --> 06:41.780 Now in event blueprint initialize widget we know that it does. 06:42.200 --> 06:49.010 Because if we remind ourselves by going back to our widget switcher and our widget switcher and initialize 06:49.010 --> 06:49.820 slot. 06:50.180 --> 06:53.540 Here's where it's finding the load screen view model. 06:53.540 --> 06:59.300 It's finding the specific load slot view model based on the slot index. 06:59.300 --> 07:05.450 It's setting its own member variable, and then it's going through each of its three children and setting 07:05.450 --> 07:12.260 each of their BP load slot view models to the load slot view model here, because those view models 07:12.260 --> 07:19.010 are set to be assigned manually, and only after assigning that view model does it call blueprint initialize 07:19.010 --> 07:19.430 widget. 07:19.430 --> 07:23.360 So we know that in blueprint initialize widget those view models are set. 07:23.360 --> 07:28.790 It's a lot like widget controller is set in the system we created using MVC. 07:28.970 --> 07:35.690 So because of that, we know that it's safe to bind to our load slot view model. 07:35.690 --> 07:45.050 If we search for BP load slot view model we can get that get BP load slot view model and we can drag 07:45.050 --> 07:49.250 off of it and assign enable select slot button. 07:49.250 --> 07:53.330 Now we're going to hook this up straight from the other bind. 07:53.330 --> 07:55.970 Not the event but the bind. 07:56.570 --> 07:59.420 As this is only fired off when clicking the button. 07:59.420 --> 08:03.590 This is as soon as that ViewModel is valid. 08:04.760 --> 08:12.440 And as soon as we get the broadcast here, we can take our button, the select slot button. 08:13.580 --> 08:20.870 Grab that, get the button from it and call set is enabled. 08:22.670 --> 08:25.910 And we'll pass in the boolean enable. 08:27.570 --> 08:28.980 Now let's test this out. 08:28.980 --> 08:30.930 We'll go back to our maps. 08:30.960 --> 08:32.340 Go to load menu. 08:32.370 --> 08:34.560 We'll save all press play. 08:34.560 --> 08:38.400 And if we select a slot it becomes disabled. 08:38.400 --> 08:40.860 Now because of that delegate broadcast. 08:40.860 --> 08:44.580 And if we select another slot, all the others become enabled. 08:45.700 --> 08:49.270 Now it's clear which one is selected, at least visually. 08:49.270 --> 08:53.530 But we also need to know which one is selected in code. 08:53.950 --> 08:59.770 We should have some load slot designated as the selected slot, and we're going to handle that next. 08:59.770 --> 09:01.000 We'll do that in the next video. 09:01.000 --> 09:06.310 For now we know that we can affect the other widgets whenever we select one of them. 09:06.610 --> 09:07.480 Pretty cool. 09:07.960 --> 09:08.590 Great job. 09:08.590 --> 09:11.080 We'll continue with this in the next video. 09:11.110 --> 09:12.190 I'll see you soon.