show_hide

import android.support.annotation.IdRes;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.os.Bundle;
import android.widget.RadioGroup;

import com.bwlq.fragment.Frag1;
import com.bwlq.fragment.Frag2;
import com.bwlq.fragment.Frag3;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends FragmentActivity {
    private FragmentManager supportFragmentManager;
    private RadioGroup radioGroup;
    private Frag1 frag1;
    private Frag2 frag2;
    private Frag3 frag3;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        radioGroup = (RadioGroup) findViewById(R.id.rg);
        supportFragmentManager = getSupportFragmentManager();
        FragmentTransaction  fragmentTransaction = supportFragmentManager.beginTransaction();
        frag1 = new Frag1();
        fragmentTransaction.add(R.id.fl, frag1).commit();

        radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup radioGroup, @IdRes int i) {

                hideFragmentAll();
                FragmentTransaction fragmentTransaction = supportFragmentManager.beginTransaction();
                switch (i) {
                    case R.id.rb1:
                        fragmentTransaction.show(frag1).commit();
                        break;
                    case R.id.rb2:
                        if (frag2 == null) {
                            frag2 = new Frag2();
                            fragmentTransaction.add(R.id.fl, frag2).commit();
                        } else {
                            fragmentTransaction.show(frag2).commit();
                        }
                        break;
                    case R.id.rb3:
                        if (frag3 == null) {
                            frag3 = new Frag3();
                            fragmentTransaction.add(R.id.fl, frag3).commit();
                        } else {
                            fragmentTransaction.show(frag3).commit();
                        }
                        break;
                }
            }
        });
    }

    private void hideFragmentAll() {
        FragmentTransaction fragmentTransaction = supportFragmentManager.beginTransaction();
        if (frag1 != null && frag1.isAdded()) {
            fragmentTransaction.hide(frag1);
        }
        if (frag2 != null && frag2.isAdded()) {
            fragmentTransaction.hide(frag2);
        }
        if (frag3 != null && frag3.isAdded()) {
            fragmentTransaction.hide(frag3);
        }
        fragmentTransaction.commit();
    }


}