一：SharedPreference如何使用

此文章只是提供一种数据保存的方式， 具体使用场景请根据需求情况自行调整。

EditText添加saveData点击事件， 保存数据。

diff --git a/res/layout/activity_voicemail_settings.xml b/res/layout/activity_voicemail_settings.xml

index cd7af05..57526f2 100755

--- a/res/layout/activity_voicemail_settings.xml

+++ b/res/layout/activity_voicemail_settings.xml

@@ -29,6 +29,7 @@

         android:imeOptions="flagForceAscii|actionDone"

         android:includeFontPadding="true"

         android:inputType="text"

+        android:onClick="saveData"

         android:paddingLeft="@dimen/focus_item_padding_x"

         android:singleLine="true"

         android:textColor="@color/lv_focused"

1. 通过getSharedPreferences("voicemail_data", MODE_PRIVATE);获取SharedPreferen对象。
2. sharedPreferences.edit();获取editor对象。
3. initData()初始化EditText数据。
4. saveData()保存输入数据。
5. mEditText.setSelection(mEditText.getText().length());此方法主要设置EditText光标位置。

diff --git a/src/com/android/settings/VoicemailSettingsActivity.java b/src/com/android/settings/VoicemailSettingsActivity.java

index 9babb18..58e929a 100755

--- a/src/com/android/settings/VoicemailSettingsActivity.java

+++ b/src/com/android/settings/VoicemailSettingsActivity.java

@@ -4,6 +4,7 @@ import android.app.Activity;

 import android.content.ComponentName;

 import android.content.Context;

 import android.content.Intent;

+import android.content.SharedPreferences;

 import android.content.pm.PackageManager;

 import android.content.pm.ResolveInfo;

 import android.os.Bundle;

@@ -12,6 +13,7 @@ import android.view.KeyEvent;

 import android.view.View;

 import android.view.Window;

 import android.widget.EditText;

+import android.widget.Toast;

 import java.util.List;

@@ -22,6 +24,10 @@ public class VoicemailSettingsActivity extends Activity implements View.OnClic

     private int mSettingsFocusHeight;

     private int mSettingsNormalHeight;

     private int mSettingsStartY;

+    private SharedPreferences sharedPreferences;

+    private SharedPreferences.Editor editor;

+    private String key;

+    private String result;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

@@ -33,7 +39,12 @@ public class VoicemailSettingsActivity extends Activity implements View.OnClic

         for (int i = 0; i < ids.length; i++) {

             strs[i] = getString(ids[i]);

         }

+        sharedPreferences = getSharedPreferences("voicemail_data", MODE_PRIVATE);

+        editor = sharedPreferences.edit();

         mEditText = (EditText) findViewById(R.id.input_number);

+        initData();

+        mEditText.setSelection(mEditText.getText().length());//光标行尾

         mSettingsRecyclerView = (SettingsRecyclerView) findViewById(R.id.voicemail_list_view);

         mSettingsAdapter = new SettingsAdapter(this, strs, this);

         mSettingsRecyclerView.setLayoutManager(mSettingsAdapter.getLayoutManager());

@@ -45,6 +56,25 @@ public class VoicemailSettingsActivity extends Activity implements View.OnClic

         mSettingsRecyclerView.setHasFixedSize(true);

     }

+    private void initData() {

+        result = sharedPreferences.getString(key, null);

+        if (result == null) {

+            mEditText.setText("");

+        } else {

+            mEditText.setText(result);

+        }

+    }

+

+    public void saveData(View view) {

+        editor.remove(key);

+        String value = mEditText.getText().toString().trim();

+        editor.putString(key, value);

+        editor.commit();

+        Toast.makeText(VoicemailSettingsActivity.this, "save success", Toast.LENGTH_SHORT).show();

+        finish();

+    }

+

+

     @Override

     public void onClick(View view) {

         Log.d("jasun", "=============onClick============");

(END)

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