一、activity間互傳：Intent+Bundle

1、不需要回傳：

第一個activity中：

        Intent intent = new Intent(MainActivity.this, MainActivityI.class);
        Bundle bundle = new Bundle();
        bundle.putSerializable("homeMessageModel", homeMessageModel);
        ...
        intent.putExtras(bundle);
        startActivity(intent);
 

第二個activity中：

        Intent intent = this.getIntent();
        Bundle bundle = intent.getExtras();
        HomeMessageModel homeMessageModel = (HomeMessageModel) bundle.getSerializable("homeMessageModel");
        ...

2、需要回傳值：

第一個activity中：

                //傳送給第二個activity資料
                Intent intent = new
 
 Intent();
                intent.setClass(getActivity(), MessageActivity.class);
                Bundle bundle = new Bundle();
                bundle.putSerializable("homeMessageModel", homeMessageModel);
                intent.putExtras(bundle);
                startActivityForResult(intent, 100);


//接受第二個activity資料
 

  @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == 100 && resultCode == 200) {
            Bundle bundle = data.getExtras();
            boolean hasPersonalMsg = bundle.getBoolean("hasPersonalMsg");
            Log.e("FeaturedFragment","hasPersonalMsg==="+hasPersonalMsg);
            if (!hasPersonalMsg) {
                mMsgDot.setVisibility(View.GONE);
            } else {
                mMsgDot.setVisibility(View.VISIBLE);
            }
        }

    }

第二個activity中：

 //接收第一個activity的資料
        intent = this.getIntent();
        if (intent != null) {
            bundle = intent.getExtras();
            if (bundle != null) {
                homeMessageModel = (HomeMessageModel) bundle.getSerializable("homeMessageModel");
            }
        }


 //返回給第一個activity的資料，
                bundle.putBoolean("hasPersonalMsg", true);
                intent.putExtras(bundle);
                this.setResult(200, intent);

二、fragment間互傳

三、activity傳值給fragment：Bundle

activity中：

                OfficeFragment mFragOffice=new OfficeFragment();
                Bundle bundleOffice = new Bundle();
                bundleOffice.putSerializable("officeMsg", officeMsg);
                mFragOffice.setArguments(bundleOffice);

fragment中

Bundle bundle = getArguments();
if (bundle != null) {
    ArrayList<HomeMsgOfficeModel> officeMsg = (ArrayList<HomeMsgOfficeModel>) bundle.getSerializable("officeMsg");
}

如果在onresume中用這種方法會報錯：

    java.lang.IllegalStateException: Fragment already active

解決辦法：

在activity中

    private ArrayList<HomeMsgOfficeModel> officeMsg = new ArrayList<>();
    private ArrayList<HomeMsgPersonalModel> personalMsg = new ArrayList<>();

    public ArrayList<HomeMsgOfficeModel> getOfficeMsg() {
        return officeMsg;
    }

    public void setOfficeMsg(ArrayList<HomeMsgOfficeModel> officeMsg) {
        this.officeMsg = officeMsg;
    }

    public ArrayList<HomeMsgPersonalModel> getPersonalMsg() {
        return personalMsg;
    }

    public void setPersonalMsg(ArrayList<HomeMsgPersonalModel> personalMsg) {
        this.personalMsg = personalMsg;
    }

    //網路獲取資料後
    personalMsg.addAll(message);
    officeMsg.addAll(gonggao);

然後在fragment中

 personalMsg=((MessageActivity)getActivity()).getPersonalMsg();//獲取activity的值
 officeMsg=((MessageActivity)getActivity()).getOfficeMsg();//獲取activity的值

四、fragment傳值給activity