活动 inheritance

Question

我有个问题。 我在每个活动中都有 2 个活动，我初始化广播接收器以获取 Internet 连接更改。 收到更改后，我通过在屏幕上显示一些文本来通知用户。

为了不多次写代码，我创建了继承自AppCompatActivity的BroadcastActivity。

现在我将带有 super() 的视图传递给 BroadcastActivity 并使用视图进行操作（更改文本、可见性等）。

问题是：这样做是最佳做法还是有更优雅的解决方案？ 如果它会导致 memory 泄漏？

谢谢您的帮助！

广播活动示例

open class BroadcastActivity : AppCompatActivity(), OnConnectionChangeListener {
    //some code
}

以及活动示例（二级活动结构类似这样）

public class MainActivity extends BroadcastActivity{
    //some code
}

PS BroadcastActivity 写在 Kotlin 和 MainActivity 上 Java。

PS 2 目前我无法切换到单一活动并寻找临时解决方案。

Answer 1

为了进一步详细说明我的评论，这里有一些“更好”的东西（再次，在我个人看来）......

ActivityKtx.kt：

fun Activity.applyBroadcastReceiver(broadcastReceiver: BroadcastReceiver) {
    lifecycle.addObserver(
        BroadcastReceiverObserver(
            BroadcastReceiverConfiguration(broadcastReceiver, this)
        )
    )
}

BroadcastReceiverObserver.kt：

/**
 * Class implementing [DefaultLifecycleObserver] which is in charge of delegating setting the
 * [BroadcastReceiver]'s registration status.
 * Registers in [Activity.onResume] and unregisters in [Activity.onPause]
 */
class BroadcastReceiverObserver(
    val broadcastReceiverConfig: BroadcastReceiverConfiguration
) : DefaultLifecycleObserver {
    var isBroadcastReceiverRegistered = false

    override fun onResume(owner: LifecycleOwner) {
        super.onResume(owner)
        if (isBroadcastReceiverRegistered.not()) {
            broadcastReceiverConfig.registerBroadcastReceiver()
            isBroadcastReceiverRegistered = true
        }

    }

    override fun onStop(owner: LifecycleOwner) {
        if (broadcastReceiverRegistered) {
            isBroadcastReceiverRegistered = false
            broadcastReceiverConfig.unregisterBroadcastReceiver()
        }
        super.onStop(owner)
    }

    // add same things for onStart() and onPause()
}

/**
 * Base class for handling a [BroadcastReceiver] registration status
 */
abstract class BroadcastReceiverConfiguration {
    abstract fun registerBroadcastReceiver()
    abstract fun unregisterBroadcastReceiver()
}

/**
 * Base class for handling the broadcast receiver
 *
 * @see [BroadcastReceiverObserver]
 */
class BroadcastReceiverConfigurationImpl constructor(
    private val broadcastReceiver: BroadcastReceiver,
    private val hostActivity: Activity
) : BroadcastReceiverConfiguration() {
    
    override fun registerBroadcastReceiver() {
        hostActivity.registerReceiver(broadcastReceiver)
    }

    override fun unregisterBroadcastReceiver() {
        hostActivity.unregisterReceiver(broadcastReceiver)
    }
}

然后像这样使用它：

SomeActivity.kt：

class SomeActivity extends AppCompatActivity {
    
    override fun onCreate() {
        super.onCreate()
        applyBroadcastReceiver(myBroadcastReceiver)
    }

瞧。 零需要子类化 Activity / AppCompatActivity / MyBaseActivity 或其他。