public class SharedPreferencesTestActivity extends Activity implements View.OnClickListener{  private EditText editText;  private TextView textView;  private Button write;  private Button read;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_shared_preferences_test);    initView();    write.setOnClickListener(this);    read.setOnClickListener(this);  }  private void initView() {    editText=(EditText)findViewById(R.id.Edit_Test);    textView=(TextView)findViewById(R.id.Text_Test);    write=(Button)findViewById(R.id.write);    read=(Button)findViewById(R.id.read);  }  @Override  public void onClick(View v) {    switch (v.getId()){      case R.id.write:        String some=editText.getText().toString();        SharedPreferences pref = SharedPreferencesTestActivity.this.getSharedPreferences("data",MODE_PRIVATE);        SharedPreferences.Editor editor = pref.edit();        editor.putString("Content",some);        editor.commit();        Toast.makeText(SharedPreferencesTestActivity.this, "寫(xiě)入成功" , Toast.LENGTH_LONG).show();        editText.setText("");        break;      case R.id.read:        SharedPreferences pre = getSharedPreferences("data",MODE_PRIVATE);        String name = pre.getString("Content","");        textView.setText(name);        Toast.makeText(SharedPreferencesTestActivity.this, "讀取成功" , Toast.LENGTH_LONG).show();        break;    }  }}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:app="http://schemas.android.com/apk/res-auto"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:orientation="vertical"  tools:context="com.fae.mobile.testActivity.SharedPreferencesTestActivity">  <LinearLayout    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:orientation="horizontal">    <EditText      android:textColor="@color/red"      android:background="@null"      android:layout_width="wrap_content"      android:layout_height="wrap_content"      android:id="@+id/Edit_Test"      android:layout_weight="1"      />    <TextView      android:textColor="@color/blue"      android:layout_width="wrap_content"      android:layout_height="wrap_content"      android:id="@+id/Text_Test"      android:layout_weight="1"/>  </LinearLayout>  <Button    android:layout_marginTop="25dp"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:id="@+id/read"    android:text="讀"/>  <Button    android:layout_marginTop="25dp"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:id="@+id/write"    android:text="寫(xiě)"/></LinearLayout>