Android--Fragment与Activity通信

package com.example.testfragment;

import com.example.testfragment.MainFargment.BackString;

import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;


public class MainActivity extends Activity implements BackString{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //静态加载
        //Intent intent = new Intent(this,MainActivity2.class);
        //startActivity(intent);
        
        MainFargment fargment = new MainFargment();
        //对Fragment通信传参数
        Bundle bundle = new Bundle();
        bundle.putString("name", "Michale");
        fargment.setArguments(bundle);
        //动态加载 FragmentManager管理者
        FragmentManager manager = getFragmentManager();
        FragmentTransaction transaction = manager.beginTransaction();
        //第一个参数指定目标 动态目标容器
        transaction.add(R.id.linearLayout1, fargment, "fargment");
        transaction.addToBackStack(null);
        transaction.commit();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public Void WriteString(String code) {
        // TODO 自动生成的方法存根
        Toast.makeText(this, code, Toast.LENGTH_SHORT).show();
        return null;
    }
}
package com.example.testfragment;

import android.app.Activity;
import android.os.Bundle;

public class MainActivity2 extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO 自动生成的方法存根
        super.onCreate(savedInstanceState);
        setContentView(R.layout.fragment_main);
    }
}
package com.example.testfragment;

import android.app.Activity;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;

public class MainFargment extends Fragment {
    private String name = "hello michale";
    public    BackString backString;
    public interface BackString
    {
        public Void WriteString(String code);
    }
    
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        // TODO 自动生成的方法存根
        //return super.onCreateView(inflater, container, savedInstanceState);
        View view=inflater.inflate(R.layout.userfragment, container, false);
        String strName = getArguments().getString("name").toString();
        EditText text = (EditText) view.findViewById(R.id.editText1);
        text.setText(strName);
        backString.WriteString(name);
        return view;
    }
    
    @Override
    public void onAttach(Activity activity) {
        // TODO 自动生成的方法存根
        backString = (BackString) activity;
        super.onAttach(activity);
    }
}
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.testfragment.MainActivity" >

    <LinearLayout
        android:id="@+id/linearLayout1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical" >
    </LinearLayout>

</RelativeLayout>
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <fragment 
        android:id="@+id/fragment1"
        android:name="com.example.testfragment.MainFargment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        />

</LinearLayout>
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <EditText
        android:id="@+id/editText1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        />

</LinearLayout>
原文地址:https://www.cnblogs.com/zxcnn/p/5018941.html