使用fragment填写连续几个表格页面

常常有这样的需求，有几个连续的表格页面需要填写，而却在最后一个页面一次性提交。当然通过几个activity不断向下传值来实现，也可以只写一个页面通过布局的隐藏与显示来实现。

这里我使用了一个activity加载多个fragment的方法来实现。

先看效果图：

MainActivity:

import android.support.v4.app.FragmentManager;import android.support.v4.app.FragmentTransaction;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;public class MainActivity extends AppCompatActivity {    private FragmentManager fm;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        fm = getSupportFragmentManager();        OneFragment oneFragment = new OneFragment();        FragmentTransaction transaction = fm.beginTransaction();        transaction.add(R.id.fragment_container,oneFragment,"OneFragment");        transaction.commit();    }    public void turnToTwo(){        OneFragment oneFragment = (OneFragment) fm.findFragmentByTag("OneFragment");        TwoFragment twoFragment = (TwoFragment) fm.findFragmentByTag("TwoFragment");        if (twoFragment==null){            TwoFragment mTwoFragment = new TwoFragment();            FragmentTransaction transaction = fm.beginTransaction();            transaction.setCustomAnimations(R.anim.slide_in_right,R.anim.slide_out_left);            transaction.add(R.id.fragment_container, mTwoFragment,"TwoFragment")                    .hide(oneFragment).commit();        }else {            FragmentTransaction transaction = fm.beginTransaction();            transaction.setCustomAnimations(R.anim.slide_in_right,R.anim.slide_out_left);            transaction.show(twoFragment).hide(oneFragment).commit();        }    }    public void turnToThree(){        TwoFragment twoFragment = (TwoFragment) fm.findFragmentByTag("TwoFragment");        ThreeFragment threeFragment = (ThreeFragment) fm.findFragmentByTag("ThreeFragment");        if (threeFragment==null){            ThreeFragment mThreeFragment = new ThreeFragment();            FragmentTransaction transaction = fm.beginTransaction();            transaction.setCustomAnimations(R.anim.slide_in_right,R.anim.slide_out_left);            transaction.add(R.id.fragment_container, mThreeFragment,"ThreeFragment")                    .hide(twoFragment).commit();        }else {            FragmentTransaction transaction = fm.beginTransaction();            transaction.setCustomAnimations(R.anim.slide_in_right,R.anim.slide_out_left);            transaction.hide(twoFragment).show(threeFragment).commit();        }    }    @Override    public void onBackPressed() {        OneFragment oneFragment = (OneFragment) fm.findFragmentByTag("OneFragment");        TwoFragment twoFragment = (TwoFragment) fm.findFragmentByTag("TwoFragment");        ThreeFragment threeFragment = (ThreeFragment) fm.findFragmentByTag("ThreeFragment");        if (threeFragment!=null&&threeFragment.isVisible()){            FragmentTransaction transaction = fm.beginTransaction();            transaction.setCustomAnimations(R.anim.slide_in_left,R.anim.slide_out_right);            transaction.hide(threeFragment).show(twoFragment).commit();        }else if (twoFragment!=null&&twoFragment.isVisible()){            FragmentTransaction transaction = fm.beginTransaction();            transaction.setCustomAnimations(R.anim.slide_in_left,R.anim.slide_out_right);            transaction.hide(twoFragment).show(oneFragment).commit();        }else {            super.onBackPressed();        }    }}

主要在onBackPressed中对fragment进行了显示隐藏不销毁的做法，其次当某一个页面加载过一次后再次加载时加载已经存在的页面对象而不是新建新的对象。

几个fragment及布局文件类似，如下：

public class OneFragment extends Fragment {    @Nullable    @Override    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {        View view = inflater.inflate(R.layout.fragment_one,container,false);        view.findViewById(R.id.btn_next).setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                ((MainActivity)getActivity()).turnToTwo();            }        });        return view;    }}

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical" android:layout_width="match_parent"    android:layout_height="match_parent"    android:background="@android:color/holo_red_light">    <EditText        android:layout_width="match_parent"        android:layout_height="40dp"        android:layout_margin="40dp"        android:layout_centerInParent="true"        android:background="@android:color/white"/>    <Button        android:id="@+id/btn_next"        android:layout_width="match_parent"        android:layout_height="40dp"        android:text="下一页"/></RelativeLayout>

其中还用到了几个xml动画，几个文件如下：

slide_in_left.xml<?xml version="1.0" encoding="utf-8"?><set xmlns:android="http://schemas.android.com/apk/res/android">    <translate android:fromXDelta="-100%p" android:toXDelta="0"        android:duration="@android:integer/config_mediumAnimTime"/></set>

slide_in_right.xml<?xml version="1.0" encoding="utf-8"?><set xmlns:android="http://schemas.android.com/apk/res/android">    <translate android:fromXDelta="100%p" android:toXDelta="0"        android:duration="@android:integer/config_mediumAnimTime"/></set>

slide_out_left.xml<?xml version="1.0" encoding="utf-8"?><set xmlns:android="http://schemas.android.com/apk/res/android">    <translate android:fromXDelta="0" android:toXDelta="-100%p"        android:duration="@android:integer/config_mediumAnimTime"/></set>

slide_out_right.xml<?xml version="1.0" encoding="utf-8"?><set xmlns:android="http://schemas.android.com/apk/res/android">    <translate android:fromXDelta="0" android:toXDelta="100%p"        android:duration="@android:integer/config_mediumAnimTime"/></set>

当你在最后一个页面需要获取前面页面的值时可以先获取前面的fragment对象，再通过该对象（该类提供获取对应值的公共方法）获取对应页面的值。如：((MainActivity)getActivity()).getSupportFragmentManager().findFragmentByTag("OneFragment");获取到fragment栈中的OneFragment。