美文网首页
Kotlin-对Intent携参取值的扩展-(借鉴)

Kotlin-对Intent携参取值的扩展-(借鉴)

作者: Cosecant | 来源:发表于2020-08-01 20:58 被阅读0次

目的: 主要是使用Kotlin扩展属性处理Intent中数据的取值

Kotlin的Property的读写扩展,下面简单举个栗子,下面案例中是为了获取Kotlin中的某个Boolean值,值可能存在于Intent中,也可能是Intent中的bundle中,具体类写法如下:

class IntentExtraBoolean(
    private val key: String? = null,
    private val defaultValue: Boolean,
    private val isAssignIntoExtras: Boolean = true
) {

    private val KProperty<*>.extraName: String
        get() = this@IntentExtraBoolean.key ?: name

    operator fun getValue(intent: Intent, property: KProperty<*>): Boolean =
        intent.extras?.getBoolean(property.extraName, defaultValue)
            ?: intent.getBooleanExtra(property.extraName, defaultValue)

    operator fun setValue(intent: Intent, property: KProperty<*>, value: Boolean?) {
        when (isAssignIntoExtras) {
            true -> when (intent.extras) {
                null -> intent.putExtras(bundleOf(property.extraName to (value ?: defaultValue)))
                else -> intent.extras?.putBoolean(property.extraName, value ?: defaultValue)
            }
            else -> intent.putExtra(property.extraName, value ?: defaultValue)
        }
    }

}

调用方式:

// 跳转地址页面中的传值
fun Activity.startMyAddressListActivity(isNeedAddress: Boolean = true) =
        forward(MyAddressListActivity::class.java,
                data = bundleOf("isNeedAddress" to isNeedAddress),
                requestCode = if (isNeedAddress) ReqCodeConstants.ChooseAddr else 0)

// 地址列表页面中的取值
class MyAddressListActivity : BasicActivity<ActivityMyAddressListBinding>(), View.OnClickListener, OnRefreshListener {

    companion object {
        private val Intent.isNeedAddress by IntentExtraBoolean(defaultValue = false)
    }

   override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        val isNeedAddress = intent.isNeedAddress; //取得传递的值
   }
    .... // 省略多行代码
}

其他的取值方式亦如,可以照样画葫芦

class IntentExtraBooleanArray(
    private val key: String? = null,
    private val isAssignIntoExtras: Boolean = true
) {

    private val KProperty<*>.extraName: String
        get() = this@IntentExtraBooleanArray.key ?: name

    operator fun getValue(intent: Intent, property: KProperty<*>): BooleanArray? =
        intent.extras?.getBooleanArray(property.extraName)
            ?: intent.getBooleanArrayExtra(property.extraName)

    operator fun setValue(intent: Intent, property: KProperty<*>, value: BooleanArray?) {
        when (isAssignIntoExtras) {
            true -> when (intent.extras) {
                null -> intent.putExtras(bundleOf(property.extraName to value))
                else -> intent.extras?.putBooleanArray(property.extraName, value)
            }
            else -> intent.putExtra(property.extraName, value)
        }
    }
}

这里做个记录,方便以后查阅!!!

相关文章

网友评论

      本文标题:Kotlin-对Intent携参取值的扩展-(借鉴)

      本文链接:https://www.haomeiwen.com/subject/krzlrktx.html