WEBVTT

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Welcome back.

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We finished the Object Detector helper class and now we need to create the camera screen.

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So inside the screens create a new Kotlin file.

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Name it as camera screen.

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Start with a new composable function.

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Name it as camera screen val context equals to local context dot current val life cycle owner equals

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to lack local lifecycle owner dot current.

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Here it's very simple.

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We are accessing the Android context in compose function.

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So we need for accessing resources, starting activities, access system services, showing toasts and

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so on.

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Here getting the current lifecycle owner for lifecycle aware operations like observing live data, lifecycle

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aware coroutines, register lifecycle observers, and so on.

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We talked a lot in the previous sections about those two concepts.

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Now val camera controller equals to remember life cycle camera controller passing the context dot apply

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set enabled use cases and set the camera controller image analysis.

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Let me explain.

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Remember creates a long lived object that survives the composition.

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Camera controller is expensive to create and should persist across UI updates.

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So let me write those notes down here and I want from you to write them, because they are very important

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and helps you to memorize everything without using.

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Remember with recreate the controller on every composition, causing camera flickering and reinitialization.

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So we use the remember, because camera controller is expensive to create and should persist across

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UI updates and recompositions, the lifecycle camera controller Manages the camera lifecycle.

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Automatically handles camera lifecycle.

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Open and close on start or stop.

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Manages camera permissions and handles configuration changes like rotation.

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Apply configure the control immediately after creation and alternative to creating a variable and calling

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methods separately.

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Set enabled use cases that set enabled use cases.

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The camera controller, dot preview use case or image capture.

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The preview use case here for camera preview and the camera controller.

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Dot image capture for taking photos.

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So here we need to take photos.

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Taking photos can combine multiple image analysis or image capture.

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So for example here we have image analysis, image capture, video capture and others.

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But for now we need that image capture.

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This is for camera control.