android - 如何根据选中的单选按钮将 Spinner 值重置为 "Select by something"

Question

我有两个单选按钮和两个微调器，两者都依赖于另一个。例如，如果我单击 Radio Button1，则表示 Spinner 可见性已隐藏。反之同。

查看和隐藏功能正常，问题是，如果我选择第一个单选按钮并在 Spinner1 中选择一些值。但现在选择错误，所以我移至单选按钮 2 并从 Spinner2 中选择一些值。 (现在第一个 Spinner1 值不会改变(即)选择的旧值。我认为每当更改 Radio Button Opposite Spinner 值设置为“Select By something”时，

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getSupportActionBar().hide(); //<< this for hide title bar
    setContentView(R.layout.scrap_report);


    // Permission StrictMode
    if (android.os.Build.VERSION.SDK_INT > 9) {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
    }

    setCurrentDateOnView();
    addListenerOnButton();

    staff_name = (Spinner) findViewById(R.id.spinner1);//staff spinner
    product_name = (Spinner) findViewById(R.id.spinner2);//product spinner
    created_date1 = (TextView) findViewById(R.id.tvDate);
    created_date2 = (TextView) findViewById(R.id.tvDate2);


    //spinner for customer name
    staff_name = (Spinner) findViewById(R.id.spinner1);
    adapter = new ArrayAdapter<String>(this, R.layout.spinner_scrap_staff, R.id.txt, listItems);
    staff_name.setAdapter(adapter);
    staff_name.setAdapter(new NothingSelectedSpinnerAdapter(adapter, R.layout.scrap_staff_nthgselect, this));

    //spinner for Products
    product_name=(Spinner)findViewById(R.id.spinner2);
    adapter2=new ArrayAdapter<String>(this,R.layout.spinner_scrap_product,R.id.txt,listItems2);
    product_name.setAdapter(adapter2);
    product_name.setAdapter(new NothingSelectedSpinnerAdapter(adapter2,R.layout.scrap_product_nthg,this));


    final RadioGroup rgroup = (RadioGroup)findViewById(R.id.radioType);
    final RadioButton Ta = (RadioButton)findViewById(R.id.type_a);
    final RadioButton Tb = (RadioButton)findViewById(R.id.type_b);

    rgroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener()     {
        @Override
        public void onCheckedChanged(RadioGroup group, int checkedId) {
            if (rgroup.getCheckedRadioButtonId() == Ta.getId()) {
                staff_names = staff_name.getSelectedItem().toString();
                product_name.setSelection(0);
                product_name.setVisibility(View.GONE);
                staff_name.setVisibility(View.VISIBLE);
            }
            else if (rgroup.getCheckedRadioButtonId() == Tb.getId()) {
                product_names = product_name.getSelectedItem().toString();
                staff_name.setSelection(0);
                staff_name.setVisibility(View.GONE);
                product_name.setVisibility(View.VISIBLE);
            }
        }
    });





   /* rgroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup group, int checkedId) {
            if(checkedId == R.id.type_a){
                staff_name.setVisibility(View.VISIBLE);
                product_name.setVisibility(View.INVISIBLE);
                staff_name = (Spinner) findViewById(R.id.spinner1);
            }
            else{
                staff_name.setVisibility(View.INVISIBLE);
                product_name.setVisibility(View.VISIBLE);
                product_name=(Spinner)findViewById(R.id.spinner2);
            }
        }
    });

    rgroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup group, int checkedId) {
            if (rgroup.getCheckedRadioButtonId() == Ta.getId()) {
                staff_names = staff_name.getSelectedItem().toString();
                product_name.setAdapter(adapter2);
            }
            else if (rgroup.getCheckedRadioButtonId() == Tb.getId()) {
                product_names = product_name.getSelectedItem().toString();
                staff_name.setAdapter(adapter);
            }
        }
    });*/

    Button submit = (Button) findViewById(R.id.loadbtn);
    assert submit != null;
    submit.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {

            staff_names = staff_name.getSelectedItem().toString();
            product_names = product_name.getSelectedItem().toString();
            createddate = created_date1.getText().toString();
            created_date = created_date2.getText().toString();
            String url_server = "http://192.168.1.13:8090/Vaari_services/getScrapRepo.php";
            new get_ScrapDate().execute(url_server);

            staff_name.setSelection(0);
            product_name.setSelection(0);

        }
    });
}

我试过了

 staff_name.setSelection(0,true);

日志:

06-28 12:43:58.356 27966-27966/com.example.vari.new_varri E/AndroidRuntime: FATAL EXCEPTION: main
                                                                        Process: com.example.vari.new_varri, PID: 27966
                                                                        java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
                                                                            at com.example.vari.new_varri.Scrap_Report$1.onCheckedChanged(Scrap_Report.java:142)
                                                                            at android.widget.RadioGroup.setCheckedId(RadioGroup.java:173)
                                                                            at android.widget.RadioGroup.-wrap0(RadioGroup.java)
                                                                            at android.widget.RadioGroup$CheckedStateTracker.onCheckedChanged(RadioGroup.java:351)
                                                                            at android.widget.CompoundButton.setChecked(CompoundButton.java:159)
                                                                            at android.widget.CompoundButton.toggle(CompoundButton.java:115)
                                                                            at android.widget.RadioButton.toggle(RadioButton.java:76)
                                                                            at android.widget.CompoundButton.performClick(CompoundButton.java:120)
                                                                            at android.view.View$PerformClick.run(View.java:21147)
                                                                            at android.os.Handler.handleCallback(Handler.java:739)
                                                                            at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                            at android.os.Looper.loop(Looper.java:148)
                                                                            at android.app.ActivityThread.main(ActivityThread.java:5417)
                                                                            at java.lang.reflect.Method.invoke(Native Method)
                                                                            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
                                                                            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

Answer 1

您可以使用

以编程方式选择

spinnerObject.setSelection(0)

如果还是不行，试试这个

spinnerObject.post(new Runnable() {
        @Override
        public void run() {
            spinnerObject.setSelection(0);
        }
    });

radibutton checkedchangelistener

    rgroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener()     {
                            @Override
                            public void onCheckedChanged(RadioGroup group, int checkedId) {
                                if (rgroup.getCheckedRadioButtonId() == Ta.getId()) {
                                    staff_names = listItems.get(spinner1Object.getSelectedItemPosition());
    spinner2Object.setSelection(0);
    spinner2Object.setVisibility(View.GONE);
    spinner1Object.setVisibility(View.VISIBLE);
                                }
                                else if (rgroup.getCheckedRadioButtonId() == Tb.getId()) {
                                    product_names = listItems2.get(spinner2Object.getSelectedItemPosition());
    spinner1Object.setSelection(0);
    spinner1Object.setVisibility(View.GONE);
    spinner2Object.setVisibility(View.VISIBLE);
                                }
                            }
                        });