2月14日学习内容

今天是将昨天所观看的视频进行代码的敲写，

数据在不同界面的传送，用Bundle方法； 

在onClick方法中写

 Intent intent=new Intent(AActivity.this,BActivity.class);
                Bundle bundle=new Bundle();
                bundle.putString("name","yyf");
                bundle.putInt("age", 20);
                intent.putExtras(bundle);
                startActivity(intent);

将值传到B界面，B界面的接收时候

 mtv1= (TextView) findViewById(R.id.tv_1);
        Bundle bundle=getIntent().getExtras();
        String name=bundle.getString("name");
        int age=bundle.getInt("age");
        mtv1.setText(name+","+age);

然后将B 的值再传到A中；

需要在B中写入代码

 mtv1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent=new Intent();
                Bundle bundle1=new Bundle();
                bundle1.putString("title","哈哈哈哈");
               intent.putExtras(bundle1);
               setResult(Activity.RESULT_OK,intent);
                finish();
            }
        });

然后将A中的startActivity(intent);修改为startActivityForResult(intent,0);

然后加上一个函数

 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        Toast.makeText(AActivity.this,data.getExtras().getString("title"),Toast.LENGTH_LONG).show();
    }

B中的title会传送到A中；

还学习了Fragment的第一节的用法；

创建了一个container的Activity，然后创建两个class继承Fragment；

package com.example.yangy.myapplication123.fragment;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

import com.example.yangy.myapplication123.R;

public class ContainerActivity extends ActionBarActivity {

    private Afragment afrgment;
    private Bfragment bfrgment;
    private Button mbutchange;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_container);

        mbutchange= (Button) findViewById(R.id.btn_change);
        mbutchange.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (bfrgment == null)
                {
                    bfrgment=new Bfragment();
                }
                getFragmentManager().beginTransaction().replace(R.id.fl_container, bfrgment).commitAllowingStateLoss();
            }
        });

        //实例化AFragment
        afrgment=new Afragment();
        //把AFragment添加到Activity中指定位置
        getFragmentManager().beginTransaction().add(R.id.fl_container,afrgment).commitAllowingStateLoss();

    }
}

package com.example.yangy.myapplication123.fragment;

import android.app.Fragment;
import android.support.annotation.Nullable;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.example.yangy.myapplication123.R;

public class Afragment extends Fragment {
    private TextView mtvtitle;
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View view=inflater.inflate(R.layout.activity_afragment,container,false);//给一个布局文件
        return view;
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {

        mtvtitle= (TextView) view.findViewById(R.id.tv_title);
        
    }
}

package com.example.yangy.myapplication123.fragment;

import android.app.Fragment;
import android.support.annotation.Nullable;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.example.yangy.myapplication123.R;

public class Bfragment extends Fragment{

    private TextView mtvtitle;
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View view=inflater.inflate(R.layout.activity_bfragment,container,false);//给一个布局文件
        return view;
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {

        mtvtitle= (TextView) view.findViewById(R.id.tv_title);

    }
}

用来更换fragment的界面；明天继续学习fragment的其他3个课程；