我有三个活动A, B和C,其中A和B是表单,并在数据库(SQLite)中填充和保存表单数据后。我使用意图从A到B,然后从B到C,我想要的是,每次我打开我的应用程序时,我想要C作为我的主屏幕,而不再是A和B。
我想共享偏好可以解决这个问题,但我找不到一个好的例子来给我一个起点。
我有三个活动A, B和C,其中A和B是表单,并在数据库(SQLite)中填充和保存表单数据后。我使用意图从A到B,然后从B到C,我想要的是,每次我打开我的应用程序时,我想要C作为我的主屏幕,而不再是A和B。
我想共享偏好可以解决这个问题,但我找不到一个好的例子来给我一个起点。
当前回答
SharedPreferences mPref;
SharedPreferences.Editor editor;
public SharedPrefrences(Context mContext) {
mPref = mContext.getSharedPreferences(Constant.SharedPreferences, Context.MODE_PRIVATE);
editor=mPref.edit();
}
public void setLocation(String latitude, String longitude) {
SharedPreferences.Editor editor = mPref.edit();
editor.putString("latitude", latitude);
editor.putString("longitude", longitude);
editor.apply();
}
public String getLatitude() {
return mPref.getString("latitude", "");
}
public String getLongitude() {
return mPref.getString("longitude", "");
}
public void setGCM(String gcm_id, String device_id) {
editor.putString("gcm_id", gcm_id);
editor.putString("device_id", device_id);
editor.apply();
}
public String getGCMId() {
return mPref.getString("gcm_id", "");
}
public String getDeviceId() {
return mPref.getString("device_id", "");
}
public void setUserData(User user){
Gson gson = new Gson();
String json = gson.toJson(user);
editor.putString("user", json);
editor.apply();
}
public User getUserData(){
Gson gson = new Gson();
String json = mPref.getString("user", "");
User user = gson.fromJson(json, User.class);
return user;
}
public void setSocialMediaStatus(SocialMedialStatus status){
Gson gson = new Gson();
String json = gson.toJson(status);
editor.putString("status", json);
editor.apply();
}
public SocialMedialStatus getSocialMediaStatus(){
Gson gson = new Gson();
String json = mPref.getString("status", "");
SocialMedialStatus status = gson.fromJson(json, SocialMedialStatus.class);
return status;
}
其他回答
public class Preferences {
public static final String PREF_NAME = "your preferences name";
@SuppressWarnings("deprecation")
public static final int MODE = Context.MODE_WORLD_WRITEABLE;
public static final String USER_ID = "USER_ID_NEW";
public static final String USER_NAME = "USER_NAME";
public static final String NAME = "NAME";
public static final String EMAIL = "EMAIL";
public static final String PHONE = "PHONE";
public static final String address = "address";
public static void writeBoolean(Context context, String key, boolean value) {
getEditor(context).putBoolean(key, value).commit();
}
public static boolean readBoolean(Context context, String key,
boolean defValue) {
return getPreferences(context).getBoolean(key, defValue);
}
public static void writeInteger(Context context, String key, int value) {
getEditor(context).putInt(key, value).commit();
}
public static int readInteger(Context context, String key, int defValue) {
return getPreferences(context).getInt(key, defValue);
}
public static void writeString(Context context, String key, String value) {
getEditor(context).putString(key, value).commit();
}
public static String readString(Context context, String key, String defValue) {
return getPreferences(context).getString(key, defValue);
}
public static void writeFloat(Context context, String key, float value) {
getEditor(context).putFloat(key, value).commit();
}
public static float readFloat(Context context, String key, float defValue) {
return getPreferences(context).getFloat(key, defValue);
}
public static void writeLong(Context context, String key, long value) {
getEditor(context).putLong(key, value).commit();
}
public static long readLong(Context context, String key, long defValue) {
return getPreferences(context).getLong(key, defValue);
}
public static SharedPreferences getPreferences(Context context) {
return context.getSharedPreferences(PREF_NAME, MODE);
}
public static Editor getEditor(Context context) {
return getPreferences(context).edit();
}
}
****使用Preferences写入值使用:-****
Preferences.writeString(getApplicationContext(),
Preferences.NAME, "dev");
****使用Preferences读取值使用:-****
Preferences.readString(getApplicationContext(), Preferences.NAME,
"");
SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.saved_high_score), newHighScore);
editor.commit();
创建SharedPreference和全局使用的最佳方法,你需要创建一个类,如下所示:
public class PreferenceHelperDemo {
private final SharedPreferences mPrefs;
public PreferenceHelperDemo(Context context) {
mPrefs = PreferenceManager.getDefaultSharedPreferences(context);
}
private String PREF_Key= "Key";
public String getKey() {
String str = mPrefs.getString(PREF_Key, "");
return str;
}
public void setKey(String pREF_Key) {
Editor mEditor = mPrefs.edit();
mEditor.putString(PREF_Key, pREF_Key);
mEditor.apply();
}
}
共享偏好是如此容易学习,所以看看这个 关于共享偏好的简单教程
import android.os.Bundle;
import android.preference.PreferenceActivity;
public class UserSettingActivity extends PreferenceActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.settings);
}
}
您可以创建自定义的SharedPreference类
public class YourPreference {
private static YourPreference yourPreference;
private SharedPreferences sharedPreferences;
public static YourPreference getInstance(Context context) {
if (yourPreference == null) {
yourPreference = new YourPreference(context);
}
return yourPreference;
}
private YourPreference(Context context) {
sharedPreferences = context.getSharedPreferences("YourCustomNamedPreference",Context.MODE_PRIVATE);
}
public void saveData(String key,String value) {
SharedPreferences.Editor prefsEditor = sharedPreferences.edit();
prefsEditor .putString(key, value);
prefsEditor.commit();
}
public String getData(String key) {
if (sharedPreferences!= null) {
return sharedPreferences.getString(key, "");
}
return "";
}
}
你可以像这样获得你的偏好实例:
YourPreference yourPrefrence = YourPreference.getInstance(context);
yourPreference.saveData(YOUR_KEY,YOUR_VALUE);
String value = yourPreference.getData(YOUR_KEY);