SharedPreferences 数据存储
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2022-05-16 17:22:04
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MainActivity.java代码
layout/main.xml
value/string.xml 配置文件
核心操作类 PerferencesServer.java
package cn.itcast.settings; import java.util.Map; import cn.itcast.service.PreferencesService; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.EditText; import android.widget.Toast; public class MainActivity extends Activity { private EditText nameText; private EditText ageText; private PreferencesService service; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); nameText = (EditText) this.findViewById(R.id.name); ageText = (EditText) this.findViewById(R.id.age); service = new PreferencesService(this); Map<String, String> params = service.getPreferences(); nameText.setText(params.get("name")); ageText.setText(params.get("age")); } public void save(View v){ String name = nameText.getText().toString(); String age = ageText.getText().toString(); service.save(name, Integer.valueOf(age)); Toast.makeText(getApplicationContext(), R.string.success, 1).show(); } }
layout/main.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/name" /> <EditText android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/name" /> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/age" /> <EditText android:layout_width="fill_parent" android:layout_height="wrap_content" android:numeric="integer" android:id="@+id/age" /> <Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/button" android:onClick="save" /> </LinearLayout>
value/string.xml 配置文件
<?xml version="1.0" encoding="utf-8"?> <resources> <string name="hello">Hello World, MainActivity!</string> <string name="app_name">软件参数设置</string> <string name="name">姓名</string> <string name="age">年龄</string> <string name="button">保存参数</string> <string name="success">保存完成</string> </resources>
核心操作类 PerferencesServer.java
package cn.itcast.service; import java.util.HashMap; import java.util.Map; import android.content.Context; import android.content.SharedPreferences; import android.content.SharedPreferences.Editor; public class PreferencesService { private Context context; public PreferencesService(Context context) { this.context = context; } /** * 保存参数 * @param name 姓名 * @param age 年龄 */ public void save(String name, Integer age) { SharedPreferences preferences = context.getSharedPreferences("itcast", Context.MODE_PRIVATE); Editor editor = preferences.edit(); editor.putString("name", name); editor.putInt("age", age); editor.commit(); } /** * 获取各项配置参数 * @return */ public Map<String, String> getPreferences(){ Map<String, String> params = new HashMap<String, String>(); SharedPreferences preferences = context.getSharedPreferences("itcast", Context.MODE_PRIVATE); params.put("name", preferences.getString("name", "")); params.put("age", String.valueOf(preferences.getInt("age", 0))); return params; } }