Remove useless class parameter. modify parseParams's return type to lazy

README.md

@@ -10,25 +10,26 @@
 
 ```kotlin
 class ReceiverActivity : AppCompatActivity() {
-    // 定义参数类型
+
+    // 定义一个 data bean
     data class Params(
             val name: String,
             val phone: String,
             val emails: ArrayList<String>?,
             val parcelableBean: ParcelableBean,
             val nestedBean: Father,
             val age: Int
-    ) : SafetyActivityParams(ReceiverActivity::class.java)
+    ) : ActivityParams<ReceiverActivity>() // 通过泛型和 host 类绑定
 
-    // 解析
-    private val args by lazy { parseParams<Params>() }
+    // 解析接收到的类型
+    private val args by parseParams<Params>()
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        setContentView(R.layout.activity_receiver)
+        val binding = ActivityReceiverBinding.inflate(layoutInflater)
+        setContentView(binding.root)
 
-        // 直接取值
-        tv_content.text = args.toJsonTree()
+        binding.tvContent.text = args.toJsonTree() // 直接取值进行使用
     }
 }
 ```
@@ -85,6 +86,6 @@ dependencies {
 -keep public class kotlin.reflect.jvm.internal.impl.builtins.* { public *; }
 ```
 
-## TODO
+## Java 兼容性
 
-Java 下反射会丢失构造器参数的名称，暂时没有找到好的方案来在 Java 下使用这个工具。
+Java 下反射会丢失构造器参数的名称，暂无兼容 Java 计划。

library/src/main/java/com/twiceyuan/safetyparams/library/SafetyParams.kt

@@ -15,36 +15,47 @@ import kotlin.reflect.jvm.javaType
 /**
  * Created by twiceYuan on 2018/3/26.
  *
- * Pass the args from intent
+ * 在 Activity、Fragment 之间类型安全地传递参数
  */
 
 sealed class SafetyParams
 
+private fun <TargetClass : Class<*>> SafetyParams.genericTypeParam(): TargetClass {
+    @Suppress("UNCHECKED_CAST")
+    return (this::class.java.genericSuperclass as ParameterizedType)
+            .actualTypeArguments[0]
+            as TargetClass
+}
+
 /**
  * 定义传递参数数据 Model 所要继承的类。例如：
  * ```
  * data class Starter(val name: String) : SafetyParams(SomeActivity::class.java)
  * ```
  */
-abstract class SafetyActivityParams(
-        @Transient private val targetClass: Class<out Activity>
-) : SafetyParams() {
+abstract class ActivityParams<ActivityType : Activity> : SafetyParams() {
+
+    private val targetClass: Class<ActivityType> by lazy { genericTypeParam() }
 
     fun launch(context: Context) {
         context.startActivityWithArgs(targetClass, this)
     }
 
     @Suppress("unused")
     fun intent(context: Context) = Intent(context, targetClass).apply {
-        putExtras(this@SafetyActivityParams.toBundle())
+        putExtras(this@ActivityParams.toBundle())
     }
 }
 
-abstract class SafetyFragmentParams<fragment : Fragment>(
-        @Transient private val targetClass: Class<fragment>
-) : SafetyParams() {
-    fun newInstance(): fragment = targetClass.newInstance().apply {
-        arguments = this@SafetyFragmentParams.toBundle()
+abstract class FragmentParams<FragmentType : Fragment> : SafetyParams() {
+
+    private val targetClass: Class<FragmentType> by lazy { genericTypeParam() }
+
+    @Suppress("UNCHECKED_CAST")
+    fun newInstance(): FragmentType {
+        return targetClass.newInstance().apply {
+            arguments = this@FragmentParams.toBundle()
+        }
     }
 }
 
@@ -68,6 +79,7 @@ private fun Context.startActivityWithArgs(targetClass: Class<out Activity>, args
 private fun SafetyParams.toBundle(): Bundle {
 
     val bundle = Bundle()
+
     // 临时读取一个 field
     @Suppress("UNCHECKED_CAST")
     fun <T> Field.read(obj: Any): T? {
@@ -193,12 +205,16 @@ private fun SafetyParams.toBundle(): Bundle {
 
 class DataBeanNotLegalException(msg: String) : RuntimeException(msg)
 
-inline fun <reified Data : SafetyParams> Activity.parseParams(): Data {
-    return intent?.extras?.toArgs() ?: throw java.lang.RuntimeException("No arguments passed.")
+inline fun <reified Data : SafetyParams> Activity.parseParams(): Lazy<Data> {
+    return lazy {
+        intent?.extras?.toArgs() ?: throw java.lang.RuntimeException("No arguments passed.")
+    }
 }
 
-inline fun <reified Data : SafetyParams> Fragment.parseParams(): Data {
-    return arguments?.toArgs() ?: throw java.lang.RuntimeException("No arguments passed.")
+inline fun <reified Data : SafetyParams> Fragment.parseParams(): Lazy<Data> {
+    return lazy {
+        arguments?.toArgs() ?: throw java.lang.RuntimeException("No arguments passed.")
+    }
 }
 
 inline fun <reified Data : SafetyParams> Bundle.toArgs(): Data {

sample/src/main/java/com/twiceyuan/safetyparams/sample/ReceiverActivity.kt

@@ -2,9 +2,8 @@ package com.twiceyuan.safetyparams.sample
 
 import android.os.Bundle
 import androidx.appcompat.app.AppCompatActivity
-import com.twiceyuan.safetyparams.R
 import com.twiceyuan.safetyparams.databinding.ActivityReceiverBinding
-import com.twiceyuan.safetyparams.library.SafetyActivityParams
+import com.twiceyuan.safetyparams.library.ActivityParams
 import com.twiceyuan.safetyparams.library.parseParams
 import com.twiceyuan.safetyparams.sample.bean.Father
 import com.twiceyuan.safetyparams.sample.bean.ParcelableBean
@@ -23,9 +22,9 @@ class ReceiverActivity : AppCompatActivity() {
             val parcelableBean: ParcelableBean,
             val nestedBean: Father,
             val age: Int
-    ) : SafetyActivityParams(ReceiverActivity::class.java)
+    ) : ActivityParams<ReceiverActivity>()
 
-    private val args by lazy { parseParams<Params>() }
+    private val args by parseParams<Params>()
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)

sample/src/main/java/com/twiceyuan/safetyparams/sample/ReceiverFragment.kt

@@ -7,7 +7,7 @@ import android.view.ViewGroup
 import androidx.fragment.app.DialogFragment
 import com.twiceyuan.safetyparams.R
 import com.twiceyuan.safetyparams.databinding.ActivityReceiverBinding
-import com.twiceyuan.safetyparams.library.SafetyFragmentParams
+import com.twiceyuan.safetyparams.library.FragmentParams
 import com.twiceyuan.safetyparams.library.parseParams
 import com.twiceyuan.safetyparams.sample.bean.Father
 import com.twiceyuan.safetyparams.sample.bean.ParcelableBean
@@ -21,9 +21,9 @@ class ReceiverFragment : DialogFragment() {
             val nestedBean: Father,
             val emails: ArrayList<String>?,
             val parcelableBean: ParcelableBean
-    ) : SafetyFragmentParams<ReceiverFragment>(ReceiverFragment::class.java)
+    ) : FragmentParams<ReceiverFragment>()
 
-    private val params by lazy { parseParams<Params>() }
+    private val params by parseParams<Params>()
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
         return inflater.inflate(R.layout.activity_receiver, container, false)