package com.example.fragmentdemo;

import android.app.Activity;

import android.app.FragmentManager;

import android.app.FragmentTransaction;

import android.content.Intent;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

public class MainActivity extends Activity {

    private FragmentManager mFragmentManager;

    private Fragment1 fragment1;

    private Fragment2 fragment2;

    private Button button1;

    private FragmentTransaction fragmentTransaction;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);

        //新建两个Fragment

        fragment1 = new Fragment1();

        fragment2 = new Fragment2();

        mFragmentManager = getFragmentManager();

        //Fragment事务

        fragmentTransaction = mFragmentManager.beginTransaction();

        //增加执行的动画效果 动画不能用我们的Tween动画，后面会有代码

        fragmentTransaction.setCustomAnimations(R.anim.animation_view, R.anim.animation_view_exit);

        //加入1个Fragment

        fragmentTransaction.add(R.id.myFrameLayout, fragment1);

        fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);

        fragmentTransaction.commit();

        button1 = (Button)findViewById(R.id.button1);

        button1.setOnClickListener(new OnClickListener() {

            @Override

            public void onClick(View v) {

                fragmentTransaction = mFragmentManager.beginTransaction();

                //执行动画，显示fragment2

                fragmentTransaction.setCustomAnimations(R.anim.animation_view, R.anim.animation_view_exit);

                if (fragment2.isAdded()) {

                    fragmentTransaction.commit();

                }else{

                    fragmentTransaction.add(R.id.myFrameLayout, fragment2);

                    fragmentTransaction.addToBackStack(null);

                    fragmentTransaction.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

    protected void onResume() {

        super.onResume();

    }

    @Override

    public void onBackPressed() {

        super.onBackPressed();

        mFragmentManager.popBackStack();

    }

}