面向AOP，代替Intent、简化传值方案

痛点

• 定义key,想名字是个麻烦事儿!
• 目标activity需要取值、赋值俩个操作!
• 需要返回结果时需重写onActivityResult方法!
• 定义requestCode,定义resultCode,"去"和"回"代码分隔两处,逻辑不连贯!
• 自定义Bean传值需要序列化!

思路

• APT根据注解生成参数容器Bean、Builder模式链式set方法赋值
• Bean中对EventBus广播、订阅
• Javassist注入,订阅时参数被同步到目标activity
• Callback同理

简单、优雅

Step 1. 给目标Activity需要传递的属性加注解 @EventParam

class TargetActivity extends AppCompatActivity {
    @EventParam
    public  Data data;

Step 2. Build Project 生成 $$EventBean

APT generated $$EventBean.java

Step 3. 跳转传值代码

TargetActivity$$EventBean
                .builder()
                .setData(new Data("sss"))//根据所加注解自动生成对应属性的set方法
                .create()
                .post(this);

others

• postBack 代替 setResult

TargetActivity$$EventBean.postBack( new Data("data") );

• postForResult 代替 startActivityForResult

TargetActivity$$EventBean
                .builder()
                .setData(new Data("sss"))//根据所加注解自动生成对应属性的set方法
                .create()
                .postForResult(this, new TargetActivity$$EventBean.Callback<Data>() {//泛型<Data>为$$EventBean.postBack所传类型
                    @Override
                    public void onResult() {
                        //it即是传回的结果,泛型<Data>
                        Log.e(" onResult= ", it.getString1());
                    }
                });

• 返回可变参数

 TargetActivity$$EventBean.postBack("data1","data2",33,true ,new Data("cData"));

 TargetActivity$$EventBean
                .builder()
                .setName( "sss" )
                .create()
                .postForResult(this, new TargetActivity$$EventBean.Callback2(){//注意:这里换成Callback2来接收可变参数数组
                    @Override
                    public void onResult() {
                        //打印出返回的数组
                        Log.e("gaom onResult= ", Arrays.toString(params));
                    }
                });

添加依赖：

项目-build.gradle

buildscript {
    repositories {
       ...
        maven { url 'https://jitpack.io' }
    }
    dependencies {
        ...
        classpath 'com.github.gm365066360.StartActivityAndEventbus:plugin:1.5'
        classpath "io.realm:realm-gradle-plugin:3.4.0"
    }
}
allprojects {
    repositories {
        maven { url 'https://jitpack.io' }
       ...
    }
}

app-build.gradle

import com.app.plugin.JavassistPlugin

apply plugin: 'com.android.application'
apply plugin: 'realm-android'
apply plugin: JavassistPlugin

...

dependencies {
    ...
    implementation 'org.greenrobot:eventbus:3.1.1'
    implementation 'com.github.gm365066360.StartActivityAndEventbus:api:1.5'
    annotationProcessor 'com.github.gm365066360.StartActivityAndEventbus:compiler:1.5'
}

对照

$$EventBean	Activity
post(this)	startActivity(intent)
postForResult(this,callback)	startActivityForResult(intent,requestCode)
.builder().setParam()	intent.putExtra(key,value)
@EventParam	getIntent().getStringExtra(key)
TargetActivity$$EventBean.postBack(object)	setResult(100,intent)