1通过Bundle（Activity向Fragment传递数据）
activity中

				Bundle bundle = new Bundle();
                bundle.putString("message", " 我喜欢享学课堂");
                BlankFragment1 bf = new BlankFragment1();
                bf.setArguments(bundle);

BlankFragment1中拿到activity中的值

 @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Bundle bundle = this.getArguments();
        String string = bundle.getString("message");
        Log.d(TAG, "onCreate: " + string);

    }

2通过接口回调机制（Fragment向Activity传递数据）
先创建回调接口IFragmentCallback

public interface IFragmentCallback {
    void sendMsgToActivity(String msg);
    String getMsgFromActivity(String msg);
}

Fragment进行回调赋值

    private IFragmentCallback fragmentCallback;
    public void setFragmentCallback(IFragmentCallback callback){
        fragmentCallback = callback;
    }
//可在button中做触发事件
fragmentCallback.sendMsgToActivity("hello, I'm from Fragment");

Activity通过设置接口回调接收数据

BlankFragment1 bf = new BlankFragment1();
               
                bf.setFragmentCallback(new IFragmentCallback() {
                    @Override
                    public void sendMsgToActivity(String msg) {
                        Toast.makeText(MainActivity.this,msg, Toast.LENGTH_SHORT).show();
                    }

                    @Override
                    public String getMsgFromActivity(String msg) {
                        return "hello, I am from activity";
                    }
                });

2.1通过接口回调机制（Activity向Fragment传递数据）

先创建回调接口IFragmentCallback

public interface IFragmentCallback {
    void sendMsgToActivity(String msg);
    String getMsgFromActivity(String msg);
}

Fragment进行回调赋值

    private IFragmentCallback fragmentCallback;
    public void setFragmentCallback(IFragmentCallback callback){
        fragmentCallback = callback;
    }
//可在button中做触发事件
String msg = fragmentCallback.getMsgFromActivity("null");
Toast.makeText(BlankFragment1.this.getContext(), msg, Toast.LENGTH_SHORT).show();

Activity通过设置接口回调接收数据

BlankFragment1 bf = new BlankFragment1();
               
                bf.setFragmentCallback(new IFragmentCallback() {
                    @Override
                    public void sendMsgToActivity(String msg) {
                     
                    }

                    @Override
                    public String getMsgFromActivity(String msg) {
                        return "hello, I am from activity";
                    }
                });

3通过eventBus