Android开发——动态功能（四）fragment详解（三）参数传递

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Fragment详解（三）

上一篇写到了点击替换fragment

这一篇写传递参数给fragment

示例代码

修改前面FragmentA的代码和ContainerActivity代码

FragmentA的java代码

package com.example.administrator.exercise.fragment;

import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.example.administrator.exercise.R;

import org.w3c.dom.Text;

public class FragmentA extends android.app.Fragment {

    private TextView tv;

	//创建一个传参的方法，把参数放入bundle中，再把bundle添加到fragment中
    public static FragmentA newInstance(String text){
        FragmentA fragmentA = new FragmentA();
        Bundle bundle = new Bundle();
        bundle.putString("text",text);
        fragmentA.setArguments(bundle);
        return fragmentA;
    }

    //返回一个视图文件，相当于setContextView一样
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_a,container,false);  //参数：fragment的布局文件，container，false
        return view;
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        tv = view.findViewById(R.id.fm_a_tv);	
        if (getArguments()!=null)	//获取传来的参数
            tv.setText(getArguments().getString("text"));
    }

}

ContainerActivity的java文件

package com.example.administrator.exercise.fragment;

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

        import com.example.administrator.exercise.R;

public class ContainerActivity extends AppCompatActivity {

    Button bt_jump;

    private FragmentA Afragment;
    private FragmentB Bfragment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_container);
        bt_jump = (Button) findViewById(R.id.container_bt);
        //给按钮设置监听
        bt_jump.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (Bfragment == null){
                    Bfragment = new FragmentB();
                }
                    getFragmentManager().beginTransaction().replace(R.id.container_fl,Bfragment).commitAllowingStateLoss(); //调用替换方法
            }
        });
        //实例化Afragment
        Afragment = FragmentA.newInstance("能传递参数了");
        //把Afragment添加到Activity中，记得调用commit
        getFragmentManager().beginTransaction().add(R.id.container_fl,Afragment).commitAllowingStateLoss();

    }
}

帮助理解图

运行结果图