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class OwnFragment : Fragment() {
    val errorMessage by string(R.string.error_message)
}

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fun View.string(@StringRes id: Int): ReadOnlyProperty<View, String>
    = StringDelegate(contextProvider, id)

fun Activity.string(@StringRes id: Int): ReadOnlyProperty<Activity, String>
    = StringDelegate(contextProvider, id)

fun Fragment.string(@StringRes id: Int): ReadOnlyProperty<Fragment, String>
    = StringDelegate(contextProvider, id)

private class StringDelegate : ReadOnlyProperty<Any, Stirng>

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class StringDelegate : ReadOnlyPropery<Any, String> {
 
    private val stringRes: Int
    private val contextProvider: () -> Context
    private var string: String? = null
  
    constructor(contextProvider: () -> Context, @StringRes stringRes: Int) {
        this.contextProvider = contextProvider
        this.stringRes = stringRes
    }

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val View.contextProvider: () -> Context
    get() = this::getContext
    
val Activity.contextProvider: () -> Context
    get() = { this }
    
val Fragment.contextProvider: () -> Context
    get() = this::getContext
    

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class OwnFragment : Fragment(), ContextProvider {

    val errorMessage by string(R.string.error_message)

    overrider fun provideContext() = context
}

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fun ContextProvider.string(@StringRes stringRes: Int): ReadOnlyProperty<ContextProvider, Stirng>
    = StringDelegate(stringRes)

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class StringDelegate : ReadOnlyPropery<ContextProvider, String> {
 
    private val stringRes: Int
    private var string: String? = null
  
    constructor(@StringRes stringRes: Int) {
        this.stringRes = stringRes
    }
  
    override fun getValue(ref: ContextProvider, property: KProperty<*>): String {

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interface ContextProvdier {
    fun provideContext(): Context
}

class OwnActivity : AppCompatActivity(), ContextProvider {
    fun provideContext() = this
}

class OwnFragment : Fragment(), ContextProvider {
    fun provideContext() = context

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private val errorMessage: TextView by view(R.id.errorMessage)

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fun <T : View> Activity.view(IdRes id: Int): ReadOnlyProperty<Activity, T> 
    = ViewFinderDelegate(id)