java - 带有 setOnItemSelectedListener 的微调器不执行方法

Question

我创建了一个微调器，它从某个数据库中获取值。微调器还有一个执行方法的 setOnItemSelectedListener。每当我单击微调器上的某个项目时，我都不会执行其中的内容。

    //Getting values from database
    myDBJ = new JobDatabaseHelper(this);
    ArrayList<String> jobname= myDBJ.getalljobname();

    Spinner spinnerJob = (Spinner) findViewById(R.id.spinnerJob);
    ArrayAdapter<String> adapterForJob = new ArrayAdapter<String>(InfoActivity.this, android.R.layout.simple_spinner_item, jobname);
    adapterForJob.notifyDataSetChanged();
    adapterForJob.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinnerJob.setAdapter(adapterForJob);
    spinnerJob.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            Toast.makeText(InfoActivity.this, "test" + i ,Toast.LENGTH_SHORT).show();
            //refreshrate();
        }

        @Override
        public void onNothingSelected(AdapterView<?> adapterView) {

        }
    });

我什至在其中制作了一条 toast 消息，以便我知道它是否有效。当我单击某个项目时，它不显示 toast 消息。我想补充的另一个细节是，这在一个名为“refreshspinners”的方法中，该方法在我的 onCreate 和 onPostResume 覆盖方法中调用。

Answer 1

你能试试静态字符串列表吗:

ArrayList<String> jobname = (ArrayList<String>) Arrays.asList(new String[] {"Engineer", "Manager", "Business developer"});

Spinner spinnerJob = (Spinner) findViewById(R.id.spinnerJob);
ArrayAdapter<String> adapterForJob = new ArrayAdapter<String>(InfoActivity.this, android.R.layout.simple_spinner_item, jobname);
adapterForJob.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinnerJob.setAdapter(adapterForJob);

spinnerJob.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
        Toast.makeText(InfoActivity.this, "test" + i ,Toast.LENGTH_SHORT).show();
        //refreshrate();
    }

    @Override
    public void onNothingSelected(AdapterView<?> adapterView) {

    }
});