我很难正确实施“收藏夹”＆＃39;我的应用程序的功能。在对象列表中移动，用户应该能够检查/取消选中某些内容作为收藏。一旦活动进入onPause();状态，它应该保存收藏夹列表（相反，布尔标记的完整列表，表示某些内容是否是收藏夹... true收藏夹，false {1}}不是最喜欢的。）显然，在进入onResume();状态时，应加载列表，以便他们可以查看他们之前标记的收藏夹。
我认为，我的问题确实来自于列表在初始化时随机化的事实。我确定我的算法已关闭，但我已经尝试了各种各样的方法，以至于我再也看不到它了。
主要活动Java
public class MainActivity extends ActionBarActivity {
Global global_main;
@Override
protected void onCreate(Bundle savedInstanceState) {
global_main = Global.getInstance("all");
}
@Override
protected void onResume(){
super.onResume();
SharedPreferences settings = getSharedPreferences(FILE_FAVORITES, 0);
for(int index = 0; index < TOTAL_QUESTIONS; index++){
boolean favFromFile = settings.getBoolean(("savedFavorite_" + String.valueOf(index)), false);
global_main.setFav(index, favFromFile);
}
}
@Override
protected void onPause(){
super.onPause();
SharedPreferences settings = getSharedPreferences(FILE_FAVORITES, 0);
SharedPreferences.Editor editor = settings.edit();
for(int index = 0; index < TOTAL_QUESTIONS; index++){
editor.putBoolean(("savedFavorite_" + String.valueOf(index)), global_main.getFav(index));
// Commit the edits!
editor.commit();
}
}
练习Java
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = getIntent();
selectedSection = intent.getStringExtra(chooseSection.chosenSection);
global = Global.getInstance(selectedSection);
}
全球课程
public class Global {
private static Global global = null;
//Current total of questions which the user has chosen
//EX: if Multiplication was chosen and has 10 questions in the array
//Then this equals 10
int CURRENT_TOTAL;
//This is the position that the first question of the user's choice starts with
//EX: If user chooses Multiplication, and the multiplication questions start at questions[19];
//Then this equals 19
int CURRENT_START;
//This is the position that the last question of the user's choice ends with
//EX: If user chooses Multiplication, and the multiplication questions end at questions[24];
//Then this equals 24
int CURRENT_END;
//Basic question structure
class questionStruct
{
String q;
String a;
int position; //original position in the array;
boolean favorite;
}
//Array of question structures
questionStruct[] questions = new questionStruct[TOTAL_QUESTIONS];
//userChoice is the choice of question type that the user has selected.
//EX: Multiplication, Division, Addition, Subtraction, or All/Default
public static Global getInstance(String userChoice) {
if(global == null)
{
global = new Global();
global.initialize();
}
global.getChoice(userChoice);
global.setQuestionsDefault();
global.randomize();
return global;
}
public void initialize() {
for (int i = 0; i < TOTAL_QUESTIONS; i++) {
questions[i] = new questionStruct();
}
questions[0].q = "Question 1 Text";
questions[0].a = "Answer";
questions[0].position = 0;
questions[1].q = "Question 2 Text";
questions[1].a = "Answer";
questions[1].position = 1;
questions[2].q = "Question 3 Text";
questions[2].a = "Answer";
questions[2].position = 2;
....ETC.
....ETC.
....ETC.
}
public void setQuestionsDefault(){
questionStruct temp = new questionStruct();
for(int index = 0; index < TOTAL_QUESTIONS; index++){
int count = questions[index].position;
temp = questions[count];
questions[count] = questions[index];
questions[index] = temp;
temp = null;
}
}
//Randomize the questions only within the range of the category
//which the user has chosen
public void randomize(){
for(int index = CURRENT_END; index >= CURRENT_START; index --)
{
//Generate random number to switch with random block
Random rand = new Random();
int currentQ = rand.nextInt((CURRENT_END - CURRENT_START) + 1) + CURRENT_START;
//Switch two Question blocks
questionStruct temp = questions[currentQ];
questions[currentQ] = questions[index];
questions[index] = temp;
}
}
public void setFav(int q, boolean b){
questions[q].favorite = b;
}
public boolean getFav(int q){
return questions[q].favorite;
}
可能与我的问题相关的一切。如果我遗漏任何东西或者某些事情没有意义，我会道歉。随意问的问题。我目前仍在改变一切以使其发挥作用，所以我可能已经复制了一些并不完全相加的东西。
编辑：我还要为＆＃34;收藏＆＃34;添加代码。按钮单击可将收藏夹变为非收藏夹，反之亦然。虽然这对于完成这项工作至关重要，但这并不是我担心正常运作的原因，因为它非常简单。但是，如果有人觉得他们想要看到它，反过来帮助我，那么就在这里。
这也是练习题Java文件：
public void setFavoriteButton(){
if(global.getFav(tempQQ)){
FAVORITE.setBackgroundColor(Color.YELLOW);
}
else{
FAVORITE.setBackgroundColor(getResources().getColor(R.color.primary));
}
}
@Override
public void onClick(View v){
switch(v.getId()){
case R.id.favorite:
updateFavorite();
break;
}
}
public void updateFavorite(){
if(global.getFav(tempQQ)){
global.setFav(tempQQ, false);
}
else{
global.setFav(tempQQ, true);
}
setFavoriteButton();
}
答案 0 :(得分：15)
我真的建议您使用更多面向对象的方法来处理您的模型。
您可以创建模型类Quiz，它可能如下所示：
class Quiz{
private boolean favorite;
private String question;
private String answer;
public Quiz(String question, String answer){
this.question = question;
this.answer = answer;
}
public boolean isFavorite() {
return favorite;
}
public void setFavorite(boolean favorite) {
this.favorite = favorite;
}
//...
}
通过这种方式，您可以创建一个Quiz列表并执行随机播放，排序，检查收藏等等：
//Create the list of questions
ArrayList<Quiz> myQuiz = new ArrayList<Quiz>();
myQuiz.add(new Quiz("Question?", "Ansewer!"));
//...
//Shuffle all!
Collections.shuffle(myQuiz);
//Iterate and check for favorites
for(Quiz q : myQuiz){
if(q.isFavorite()){
//this is favorite!
}
}
关于数据的持久性，您可以考虑采用 SQLite 方法，或仅考虑SharedPreference中的serialize your list and save it。
答案 1 :(得分：2)
由于我相信您将收藏状态存储在questionStruct课程中，因此您无需在onResume()中恢复收藏状态，您可以将其保存在onCreate()中。
正如@bonnyz已回答，您可以使用Collections.shuffle(myQuiz);在onResume()中随机播放您的项目，然后使用notifyDataSetChanged()刷新您的适配器。