java - 保存和获取具有共享首选项的微调项目

Question

我在将微调项目保存到共享首选项时遇到问题。我所说的问题是我真的不知道该怎么做。如果有人知道的话，如果有人能真正向我解释，那就太好了。提前致谢:)

所以我设置了按钮 1 以打开带有微调器的对话框，并且在微调器中我有 3 个项目(在 strings.xml 中声明)。我应该使用共享首选项将微调器默认设置为项目 1:“-”，如果用户选择项目 2“lang1”或“lang2”，则应将其保存在应用程序中。这样，当我下次打开应用程序时，它的“lang1”或“lang2”取决于选择。

其他一切都工作正常。

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    SharedPreferences sharedpreferences;
    public static final String mypreference = "mypref";

    int spinnerPosition;
    public Button btnTrans, btnSelect,btnInput,btnCheck;
    public TextView tv_title, tv_message;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btnSelect= (Button) findViewById(R.id.btnLanguage);
        btnInput = (Button) findViewById(R.id.btnInput);
        btnTrans = (Button) findViewById(R.id.btnTranslate);

        btnTrans.setOnClickListener((View.OnClickListener) this);
        btnInput.setOnClickListener(this);
        btnSelect.setOnClickListener(this);

        Spinner lang_spinner = (Spinner) findViewById(R.id.lang_spinner);

    }

    public void onClick(View v)
        {
        int id=v.getId();

        switch (id){
            case R.id.btnLanguage:

                AlertDialog.Builder mBuilder = new AlertDialog.Builder(MainActivity.this);
                View mView = getLayoutInflater().inflate(R.layout.language_dialog, null);
                mBuilder.setTitle("select language");
                final Spinner mSpinner = (Spinner) mView.findViewById(R.id.lang_spinner);
                final ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this,
                        android.R.layout.simple_spinner_item, getResources().getStringArray(R.array.lang_array));

                adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
                mSpinner.setAdapter(adapter);
                mSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
                    SharedPreferences.Editor editor = sharedpreferences.edit();

                    //SELECTING LANGUAGE switch case (translate btn)-
                    @Override
                    public void onItemSelected(AdapterView<?> adapterView, View view, int position, long id) {
                        Object item = adapterView.getItemAtPosition(position);
                        if (item != null) {

                            switch (position) {
                                case 0:
                                    item = "-";
                                    btnTrans.setOnClickListener(new View.OnClickListener() {
                                        @Override
                                        public void onClick(View view) {
                                            Toast.makeText(getApplicationContext(), R.string.nista, Toast.LENGTH_LONG).show();
                                        }
                                    });
                                    break;
                                case 1:
                                    item = "lang1";
                                    btnTrans.setOnClickListener(new View.OnClickListener() {
                                        @Override
                                        public void onClick(View view) {
                                            Toast.makeText(getApplicationContext(), R.string.hrvatski, Toast.LENGTH_LONG).show();
                                        }
                                    });
                                    break;
                                case 2:
                                    item = "lang2";
                                    btnTrans.setOnClickListener(new View.OnClickListener() {
                                        @Override
                                        public void onClick(View view) {
                                            Toast.makeText(getApplicationContext(), R.string.english, Toast.LENGTH_LONG).show();
                                        }
                                    });
                                    break;
                            }

                        }
                        //on selected save

                    }

                    @Override
                    public void onNothingSelected(AdapterView<?> adapterView) {
                        //nothing selected "-"
                    }
                });

Answer 1

我的代表人数不到 50，所以我在这里发布链接以共享偏好 https://www.google.com/amp/s/www.geeksforgeeks.org/shared-preferences-in-android-with-examples/amp/

从微调器中获取您的 Lang 并将值存储在共享偏好中。