Android Fragment在ViewPager中替换

大致效果如下

 ](http://upload-images.jianshu.io/upload_images/1168278-ee8e30f37fdcc193.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)

在viewPager中有5个fragment，在第二个fragment中有一个切换按钮，可以将自己切换为fragment6，之后点击fragment6中的按钮可以切换回来。。。。参考:

http://blog.csdn.net/z13759561330/article/details/40737381/

具体代码如下

FragmentActivity.class

 
 
package com.lsp.otherandroidtest.fragment_test;
 
 
import android.os.Bundle;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentManager;
 import android.support.v4.app.FragmentPagerAdapter;
 import android.support.v4.app.FragmentTransaction;
 import android.support.v4.view.ViewPager;
 import android.support.v7.app.AppCompatActivity;
 import android.view.ViewGroup;
 
 
import com.lsp.otherandroidtest.R;
 
 
import java.util.ArrayList;
 import java.util.List;
 
 
/**
 
 
 
  
 
Created by lsp on 2016/8/5.
 */
 public class FragmentViewPagerTest extends AppCompatActivity {
 private ViewPager viewPager;
 private FragmentPagerAdapter adapter;
 private List fragmentList;
 
private TestFragment testFragment1;
 private TestFragment testFragment2;
 private TestFragment testFragment3;
 private TestFragment testFragment4;
 private TestFragment testFragment5;
 
private TestFragment testFragment6;
 
private boolean fragmentsUpdateFlag[] = {false, false, false, false, false};
 
@Override
 public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_fragment_test);
 
 initViewPager();
 
}
 
private void initViewPager() {
 
 viewPager = (ViewPager) findViewById(R.id.id_vp);

 testFragment1 = TestFragment.getFragment("1");
 testFragment2 = TestFragment.getFragment("2");
 testFragment3 = TestFragment.getFragment("3");
 testFragment4 = TestFragment.getFragment("4");
 testFragment5 = TestFragment.getFragment("5");

 testFragment6 = TestFragment.getFragment("6");

 fragmentList = new ArrayList<>();
 fragmentList.add(testFragment1);
 fragmentList.add(testFragment2);
 fragmentList.add(testFragment3);
 fragmentList.add(testFragment4);
 fragmentList.add(testFragment5);

 adapter = new MyAdapter(getSupportFragmentManager());
 viewPager.setOffscreenPageLimit(5);
 viewPager.setAdapter(adapter);

 testFragment2.setTransListener(new TestFragment.onTranslateClick() {
     @Override
     public void onClick(String msg) {
         //点击切换按钮
         //设置fragment2的tag为true
         fragmentsUpdateFlag[1] = true;
         //替换fragment
         fragmentList.set(1, testFragment6);
         adapter.notifyDataSetChanged();
     }
 });
 testFragment6.setTransListener(new TestFragment.onTranslateClick() {
     @Override
     public void onClick(String msg) {
         //点击切换按钮
         //设置fragment2的tag为true
         fragmentsUpdateFlag[1] = true;
         //替换fragment
         fragmentList.set(1, testFragment6);
         //刷新
         adapter.notifyDataSetChanged();
     }
 });
 
}
 
 
 
 
 
public class MyAdapter extends FragmentPagerAdapter {

    private FragmentManager fm;

    public MyAdapter(FragmentManager fm) {
        super(fm);
        this.fm = fm;
    }


    @Override
    public Fragment getItem(int position) {
        return fragmentList.get(position % fragmentList.size());
    }

    @Override
    public int getCount() {
        return fragmentList.size();
    }

    @Override
    public int getItemPosition(Object object) {
        return POSITION_NONE;
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        //得到缓存的fragment

        Fragment fragment = (Fragment) super.instantiateItem(container, position);

        //得到tag


        String fragmentTag = fragment.getTag();

        if (fragmentsUpdateFlag[position % fragmentsUpdateFlag.length]) {

            //如果这个fragment需要更新

            FragmentTransaction ft = fm.beginTransaction();

            //移除旧的fragment

            ft.remove(fragment);

            //换成新的fragment

            fragment = fragmentList.get(position % fragmentList.size());

            //添加新fragment时必须用前面获得的tag ❶

            ft.add(container.getId(), fragment, fragmentTag);

            ft.attach(fragment);

            ft.commit();


            //复位更新标志

            fragmentsUpdateFlag[position % fragmentsUpdateFlag.length] = false;

        }


        return fragment;
    }


}
 
 
}
 
 

FragmentActivity.XML

 
  android:orientation="vertical" android:layout_width="match_parent"
 android:layout_height="match_parent">
  android:id="@+id/id_vp"
 android:layout_width="match_parent"
 android:layout_height="match_parent"/>
 
 
 

TestFragment.class

 package com.lsp.otherandroidtest.fragment_test;
 
 
import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.support.v4.app.Fragment;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.TextView;
 
 
import com.lsp.otherandroidtest.R;
 
 
/**
 
 
 
  
Created by lsp on 2016/8/5.
 */
 public class TestFragment extends Fragment {
 private View view;
 private String msg;
 private onTranslateClick transListener;
 
 
 
 
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    view = inflater.inflate(R.layout.fragment_test,null);
    msg = getArguments().getString("msg");
    ((TextView)view.findViewById(R.id.id_tv)).setText(msg);

    if("2".equals(msg)||"6".equals(msg))
    (view.findViewById(R.id.id_btn)).setVisibility(View.VISIBLE);


    (view.findViewById(R.id.id_btn)).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            transListener.onClick(msg);
        }
    });
    return view;

}

public void setTransListener(onTranslateClick listener){
    this.transListener = listener;
}

public interface onTranslateClick{
    void onClick(String msg);
}

public static TestFragment getFragment(String msg){
    TestFragment testFragment= new TestFragment();
    Bundle bundle = new Bundle();
    bundle.putString("msg",msg);
    testFragment.setArguments(bundle);

    return testFragment;

}
 
 
}
 
 

TestFragment.xml

 
  android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical">
 
 



 
 

 
 

这里用来表示要替换的Fragment

Paste_Image.png

在TestFragment中为按钮做了回调，当点击Fragment的按钮时，在FragmentActivity中处理，

Paste_Image.png

这里是点击fragment中的回调处理,

Paste_Image.png

最主要的处理部分在instantiateItem方法中..