存储

DataActivity.java

package com.hanqi.test2;

import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class DataActivity1 extends AppCompatActivity {
    EditText et_1;
    EditText et_2;
    SharedPreferences sp;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_data1);
        et_1=(EditText)findViewById(R.id.et_1);
        et_2=(EditText)findViewById(R.id.et_2);
        sp=getSharedPreferences("mydata",MODE_PRIVATE);
    }
    public void bt_1onclick(View v){
        String key= et_1.getText().toString();
        String value= et_2.getText().toString();
        if (key.length()==0 || value.length()==0){
            Toast.makeText(DataActivity1.this, "key,value不能为空", Toast.LENGTH_SHORT).show();
        }
        SharedPreferences.Editor editor= sp.edit();
        editor.putString(key,value);
        boolean b = editor.commit();
        if (b){
            Toast.makeText(DataActivity1.this, "yes", Toast.LENGTH_SHORT).show();
        }else {
            Toast.makeText(DataActivity1.this, "no", Toast.LENGTH_SHORT).show();
        }

    }
    public void bt_2onclick(View v){
        String key = et_1.getText().toString();
        et_2.setText(sp.getString(key,"没有发现key"));


    }
}

layout_data1.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.hanqi.test2.DataActivity1"
    android:orientation="vertical">
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/et_1"
        android:hint="key"/>
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/et_2"
        android:hint="value"/>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="保存"
            android:onClick="bt_1onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="读取"
            android:onClick="bt_2onclick"/>
    </LinearLayout>

</LinearLayout>