Question

我想保存几个片段的用户输入，我尝试使用方法onSaveInstanceState来保存状态和方法onActivityCreated来恢复数据，我的来源是：

package com.example.recepcionauto.app;


import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;


/**
 * A simple {@link android.support.v4.app.Fragment} subclass.
 *
 */
public class Cliente extends Fragment {


    private EditText txtRut;
    String rut = null;

    public Cliente() { }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_cliente, container, false);
    }


    @Override
    public void onActivityCreated(Bundle savedState) {
        super.onActivityCreated(savedState);
        if (savedState != null) {
            // Restore last state for checked position.
            rut = savedState.getString("rut");
            txtRut = (EditText) getActivity().findViewById(R.id.txtRut);
            txtRut.setText(rut);
            Log.v("Log", "Recuperando del Bundle");
        }
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        outState.putString("rut", rut);
        super.onSaveInstanceState(outState);
        Log.v("Log", "Guardando en el Bundle");
    }

    @Override
    public void onPause( ) {
        Bundle outState = new Bundle( );
        outState.putString("rut", rut);
        super.onPause();
        Log.v("Log", "Se ejecuto onPause( )");
    }
}

这是我的活动，是listview和fragmentlayout

的视图

package com.autocastillo.recepcionauto.app;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.ActionBarActivity;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;

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


public class Principal extends ActionBarActivity {

    private ListView lvMenu;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lvMenu = (ListView) findViewById(R.id.lvMenu);

        List<String> lmenu = new ArrayList<String>();
        lmenu.add("Cliente");
        lmenu.add("Vehiculo");
        lmenu.add("Conductor");
        lmenu.add("Accesorios");
        lmenu.add("Resumen");

        FragmentManager fm = getSupportFragmentManager();
        FragmentTransaction transaction = fm.beginTransaction();
        Fragment startFragment = new Cliente( );
        transaction.add(R.id.myFragment,startFragment);
        transaction.commit();


        ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,lmenu );
        lvMenu.setAdapter(arrayAdapter);

        lvMenu.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {

                //Toast.makeText(Principal.this, "You Clicked at " + i, Toast.LENGTH_SHORT).show();


                Fragment newFragment=null;

                switch (i){
                    case 0:{
                        //Toast.makeText(Principal.this, "Cliente " + i, Toast.LENGTH_SHORT).show();
                        newFragment = new Cliente( );
                        break;
                    }
                    case 1:{
                        newFragment = new Vehiculo( );
                        break;
                    }
                }

                FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
                transaction.replace(R.id.myFragment,newFragment);
                transaction.addToBackStack(null);
                transaction.commit();

                Log.v("Prueba", "llamo a itemclick");
            }
        });

    }


    @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
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        Log.v("Log", "Guardando en el Bundle");
    }


    @Override
    protected void onRestoreInstanceState(Bundle inState) {
    }

}

有什么问题？，onSaveInstanceState不起作用，我尝试使用putSerialize而且没什么，请感谢您的合作

Answer 1

如果要保存的是Fragment状态，请查看此other answer，这是一个解释而非示例。您应该使用getSupportFragmentManager()实例中的putFragment和getFragment方法。

我觉得我自己使用这两个坏男孩有点晚了，但他们非常有用。让我给你一个提示添加位置的提示：

putFragment

在Principal活动中，直接在onSaveInstanceState方法中添加。每个片段要调用一次：

public void onSaveInstanceState(Bundle outState) {
    Cliente fragment = getSupportFragmentManager().findFragmentById(R.id.myFragment);
    getSupportFragmentManager().putFragment(outState, "cliente", fragment);
}

getFragment

您可以（并且应该，实际上）在getFragment内使用onCreate。使用已传递的savedInstanceState变量，稍微更改初始化片段的方式：

FragmentManager fm = getSupportFragmentManager();
FragmentTransaction transaction = fm.beginTransaction();
Fragment startFragment = null;
if(savedInstanceState == null) { // first open
    startFragment = new Cliente( );
} else { // rotation, change where the fragment was already there
    startFragment = fm.getFragment(savedInstanceState, "cliente");
}

transaction.add(R.id.myFragment,startFragment);
transaction.commit();

Android将用户输入保存在几个片段中

1 个答案:

putFragment

getFragment