Activity与Fragment通信

1、在fragment里设置一个方法

public class MyFragment extends Fragment {
    private String mText;

    public void setPosition(String text) {
        mText = text;
    }
}

2、activity调用fragment的方法

public class FragmentActivity extends AppCompatActivity {

    private MyFragment mFragment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fragment);
        mFragment = new MyFragment();
        getSupportFragmentManager()
                .beginTransaction()
                .replace(R.id.container, mFragment)
                .commit();
        mFragment.setPosition("lalala");
    }

}

这样就把activity里数据传到fragment