Android 开发笔记___存储方式__共享参数__sharedprefences

Posted 2020-09-26 alm

 

android 的数据存储方式有四种，这次是【共享参数__sharedprefences】

听起来挺别扭的，平时看到的app里面，当用户删除了一些软件以后下次安装，发现原来的设置还在，这种情况就是把一些用户的设置保存在手机里面的一个存储区域，

• 格式是XML
• key__Value
• 不方便保存关系比较复杂的数据

write

  1 package com.example.alimjan.hello_world;
  2 
  3 /**
  4  * Created by alimjan on 7/4/2017.
  5  */
  6 
  7         import android.content.Context;
  8         import android.content.Intent;
  9         import android.content.SharedPreferences;
 10         import android.os.Bundle;
 11         import android.support.v7.app.AppCompatActivity;
 12         import android.view.View;
 13         import android.view.View.OnClickListener;
 14         import android.widget.AdapterView;
 15         import android.widget.ArrayAdapter;
 16         import android.widget.EditText;
 17         import android.widget.Spinner;
 18         import android.widget.Toast;
 19         import android.widget.AdapterView.OnItemSelectedListener;
 20 
 21         import com.example.alimjan.hello_world.Utils.DateUtil;
 22 
 23 public class class_4_1_1 extends AppCompatActivity implements OnClickListener {
 24 
 25     private SharedPreferences mShared;
 26     private EditText et_name;
 27     private EditText et_age;
 28     private EditText et_height;
 29     private EditText et_weight;
 30     private boolean bMarried = false;
 31 
 32     @Override
 33     protected void onCreate(Bundle savedInstanceState) {
 34         super.onCreate(savedInstanceState);
 35         setContentView(R.layout.code_4_1_1);
 36         et_name = (EditText) findViewById(R.id.et_name);
 37         et_age = (EditText) findViewById(R.id.et_age);
 38         et_height = (EditText) findViewById(R.id.et_height);
 39         et_weight = (EditText) findViewById(R.id.et_weight);
 40         findViewById(R.id.btn_save).setOnClickListener(this);
 41 
 42         ArrayAdapter<String> typeAdapter = new ArrayAdapter<String>(this,
 43                 R.layout.item_select, typeArray);
 44         typeAdapter.setDropDownViewResource(R.layout.item_dropdown);
 45         Spinner sp_married = (Spinner) findViewById(R.id.sp_married);
 46         sp_married.setPrompt("请选择婚姻状况");
 47         sp_married.setAdapter(typeAdapter);
 48         sp_married.setSelection(0);
 49         sp_married.setOnItemSelectedListener(new TypeSelectedListener());
 50 
 51         mShared = getSharedPreferences("share", MODE_PRIVATE);
 52     }
 53 
 54     private String[] typeArray = {"未婚", "已婚"};
 55     class TypeSelectedListener implements OnItemSelectedListener {
 56         public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
 57             bMarried = (arg2==0)?false:true;
 58         }
 59 
 60         public void onNothingSelected(AdapterView<?> arg0) {
 61         }
 62     }
 63 
 64     @Override
 65     public void onClick(View v) {
 66         if (v.getId() == R.id.btn_save) {
 67             String name = et_name.getText().toString();
 68             String age = et_age.getText().toString();
 69             String height = et_height.getText().toString();
 70             String weight = et_weight.getText().toString();
 71             if (name==null || name.length()<=0) {
 72                 showToast("请先填写姓名");
 73                 return;
 74             }
 75             if (age==null || age.length()<=0) {
 76                 showToast("请先填写年龄");
 77                 return;
 78             }
 79             if (height==null || height.length()<=0) {
 80                 showToast("请先填写身高");
 81                 return;
 82             }
 83             if (weight==null || weight.length()<=0) {
 84                 showToast("请先填写体重");
 85                 return;
 86             }
 87 
 88             SharedPreferences.Editor editor = mShared.edit();
 89             editor.putString("name", name);
 90             editor.putInt("age", Integer.parseInt(age));
 91             editor.putLong("height", Long.parseLong(height));
 92             editor.putFloat("weight", Float.parseFloat(weight));
 93             editor.putBoolean("married", bMarried);
 94             editor.putString("update_time", DateUtil.getCurDateStr("yyyy-MM-dd HH:mm:ss"));
 95             editor.commit();
 96             showToast("数据已写入共享参数");
 97         }
 98     }
 99 
100     private void showToast(String desc) {
101         Toast.makeText(this, desc, Toast.LENGTH_SHORT).show();
102     }
103 
104     public static void startHome(Context mContext) {
105         Intent intent = new Intent(mContext, class_4_1_1.class);
106         mContext.startActivity(intent);
107     }
108 
109 
110 }

  1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  2     android:layout_width="match_parent"
  3     android:layout_height="match_parent"
  4     android:focusable="true"
  5     android:focusableInTouchMode="true"
  6     android:orientation="vertical"
  7     android:padding="10dp" >
  8 
  9     <RelativeLayout
 10         android:layout_width="match_parent"
 11         android:layout_height="50dp" >
 12 
 13         <TextView
 14             android:id="@+id/tv_name"
 15             android:layout_width="wrap_content"
 16             android:layout_height="match_parent"
 17             android:layout_alignParentLeft="true"
 18             android:gravity="center"
 19             android:text="姓名："
 20             android:textColor="@color/black"
 21             android:textSize="17sp" />
 22 
 23         <EditText
 24             android:id="@+id/et_name"
 25             android:layout_width="match_parent"
 26             android:layout_height="match_parent"
 27             android:layout_marginBottom="5dp"
 28             android:layout_marginTop="5dp"
 29             android:layout_toRightOf="@+id/tv_name"
 30             android:background="@drawable/editext_selector"
 31             android:gravity="left|center"
 32             android:hint="请输入姓名"
 33             android:inputType="text"
 34             android:maxLength="12"
 35             android:textColor="@color/black"
 36             android:textColorHint="@color/grey"
 37             android:textCursorDrawable="@drawable/text_cursor"
 38             android:textSize="17sp" />
 39     </RelativeLayout>
 40 
 41     <RelativeLayout
 42         android:layout_width="match_parent"
 43         android:layout_height="50dp" >
 44 
 45         <TextView
 46             android:id="@+id/tv_age"
 47             android:layout_width="wrap_content"
 48             android:layout_height="match_parent"
 49             android:layout_alignParentLeft="true"
 50             android:gravity="center"
 51             android:text="年龄："
 52             android:textColor="@color/black"
 53             android:textSize="17sp" />
 54 
 55         <EditText
 56             android:id="@+id/et_age"
 57             android:layout_width="match_parent"
 58             android:layout_height="match_parent"
 59             android:layout_marginBottom="5dp"
 60             android:layout_marginTop="5dp"
 61             android:layout_toRightOf="@+id/tv_age"
 62             android:background="@drawable/editext_selector"
 63             android:gravity="left|center"
 64             android:hint="请输入年龄"
 65             android:inputType="number"
 66             android:maxLength="2"
 67             android:textColor="@color/black"
 68             android:textColorHint="@color/grey"
 69             android:textCursorDrawable="@drawable/text_cursor"
 70             android:textSize="17sp" />
 71     </RelativeLayout>
 72 
 73     <RelativeLayout
 74         android:layout_width="match_parent"
 75         android:layout_height="50dp" >
 76 
 77         <TextView
 78             android:id="@+id/tv_height"
 79             android:layout_width="wrap_content"
 80             android:layout_height="match_parent"
 81             android:layout_alignParentLeft="true"
 82             android:gravity="center"
 83             android:text="身高："
 84             android:textColor="@color/black"
 85             android:textSize="17sp" />
 86 
 87         <EditText
 88             android:id="@+id/et_height"
 89             android:layout_width="match_parent"
 90             android:layout_height="match_parent"
 91             android:layout_marginBottom="5dp"
 92             android:layout_marginTop="5dp"
 93             android:layout_toRightOf="@+id/tv_height"
 94             android:background="@drawable/editext_selector"
 95             android:gravity="left|center"
 96             android:hint="请输入身高"
 97             android:inputType="number"
 98             android:maxLength="3"
 99             android:textColor="@color/black"
100             android:textColorHint="@color/grey"
101             android:textCursorDrawable="@drawable/text_cursor"
102             android:textSize="17sp" />
103     </RelativeLayout>
104 
105     <RelativeLayout
106         android:layout_width="match_parent"
107         android:layout_height="50dp" >
108 
109         <TextView
110             android:id="@+id/tv_weight"
111             android:layout_width="wrap_content"
112             android:layout_height="match_parent"
113             android:layout_alignParentLeft="true"
114             android:gravity="center"
115             android:text="体重："
116             android:textColor="@color/black"
117             android:textSize="17sp" />
118 
119         <EditText
120             android:id="@+id/et_weight"
121             android:layout_width="match_parent"
122             android:layout_height="match_parent"
123             android:layout_marginBottom="5dp"
124             android:layout_marginTop="5dp"
125             android:layout_toRightOf="@+id/tv_weight"
126             android:background="@drawable/editext_selector"
127             android:gravity="left|center"
128             android:hint="请输入体重"
129             android:inputType="numberDecimal"
130             android:maxLength="5"
131             android:textColor="@color/black"
132             android:textColorHint="@color/grey"
133             android:textCursorDrawable="@drawable/text_cursor"
134             android:textSize="17sp" />
135     </RelativeLayout>
136 
137     <RelativeLayout
138         android:layout_width="match_parent"
139         android:layout_height="50dp" >
140 
141         <TextView
142             android:id="@+id/tv_married"
143             android:layout_width="wrap_content"
144             android:layout_height="match_parent"
145             android:layout_alignParentLeft="true"
146             android:gravity="center"
147             android:text="婚否："
148             android:textColor="@color/black"
149             android:textSize="17sp" />
150 
151         <Spinner
152             android:id="@+id/sp_married"
153             android:layout_width="match_parent"
154             android:layout_height="match_parent"
155             android:layout_toRightOf="@+id/tv_married"
156             android:gravity="left|center"
157             android:spinnerMode="dialog" />
158     </RelativeLayout>
159 
160     <Button
161         android:id="@+id/btn_save"
162         android:layout_width="match_parent"
163         android:layout_height="wrap_content"
164         android:text="保存到共享参数"
165         android:textColor="@color/black"
166         android:textSize="20sp" />
167 
168 </LinearLayout>

 

read

 1 package com.example.alimjan.hello_world;
 2 
 3 import java.util.Map;
 4 
 5 /**
 6  * Created by alimjan on 7/4/2017.
 7  */
 8 
 9 import android.content.Context;
10 import android.content.Intent;
11 import android.content.SharedPreferences;
12         import android.os.Bundle;
13         import android.support.v7.app.AppCompatActivity;
14         import android.widget.TextView;
15 
16 public class class_4_1_1_1 extends AppCompatActivity {
17 
18     private SharedPreferences mShared;
19     private TextView tv_share;
20 
21     @Override
22     protected void onCreate(Bundle savedInstanceState) {
23         super.onCreate(savedInstanceState);
24         setContentView(R.layout.code_4_1_1_1);
25         tv_share = (TextView) findViewById(R.id.tv_share);
26         readSharedPreferences();
27     }
28 
29     private void readSharedPreferences() {
30         mShared = getSharedPreferences("share", MODE_PRIVATE);
31         String desc = "共享参数中保存的信息如下：";
32         Map<String, Object> mapParam = (Map<String, Object>) mShared.getAll();
33         for (Map.Entry<String, Object> item_map : mapParam.entrySet()) {
34             String key = item_map.getKey();
35             Object value = item_map.getValue();
36             if (value instanceof String) {
37                 desc = String.format("%s\\n　%s的取值为%s", desc, key,
38                         mShared.getString(key, ""));
39             } else if (value instanceof Integer) {
40                 desc = String.format("%s\\n　%s的取值为%d", desc, key,
41                         mShared.getInt(key, 0));
42             } else if (value instanceof Float) {
43                 desc = String.format("%s\\n　%s的取值为%f", desc, key,
44                         mShared.getFloat(key, 0.0f));
45             } else if (value instanceof Boolean) {
46                 desc = String.format("%s\\n　%s的取值为%b", desc, key,
47                         mShared.getBoolean(key, false));
48             } else if (value instanceof Long) {
49                 desc = String.format("%s\\n　%s的取值为%d", desc, key,
50                         mShared.getLong(key, 0l));
51             } else {
52                 desc = String.format("%s\\n参数%s的取值为未知类型", desc, key);
53             }
54         }
55         if (mapParam==null || mapParam.size()<=0) {
56             desc = "共享参数中保存的信息为空";
57         }
58         tv_share.setText(desc);
59     }
60 
61     public static void startHome(Context mContext) {
62         Intent intent = new Intent(mContext, class_4_1_1_1.class);
63         mContext.startActivity(intent);
64     }
65 
66 }

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     android:layout_width="match_parent"
 3     android:layout_height="match_parent"
 4     android:focusable="true"
 5     android:focusableInTouchMode="true"
 6     android:orientation="vertical"
 7     android:padding="10dp" >
 8 
 9     <TextView
10         android:id="@+id/tv_share"
11         android:layout_width="match_parent"
12         android:layout_height="wrap_content"
13         android:textColor="@color/black"
14         android:textSize="17sp" />
15 
16 </LinearLayout>