微调烤箱吐司不显示

Question

微调控制器有一个乐队流派的数组列表，当选择微调控制器中的任何类型时，它将显示一个吐司，点击微调器时没有显示吐司，代码不显示任何错误？任何想法为什么？

String spinnerSelection = null; 
    Spinner spinner = null; 

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



     ArrayAdapter<String> adapter = new ArrayAdapter<>(
       this, android.R.layout.simple_spinner_item, spinnerContent); 
     adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 


     spinner = (Spinner) findViewById(R.id.spinner); 
     spinner.setAdapter(adapter); 



     Button button = (Button) findViewById(R.id.button); 
     button.setOnClickListener(new View.OnClickListener() { 



                     public void onItemSelected(AdapterView<?>parent, View v, int position, long id) { 
     { 

      Toast.makeText(getBaseContext(),"Hell Yeah", Toast.LENGTH_SHORT).show(); 
     } 
    } 
    public void onNothingSelected(AdapterView<?> arg0) { 
    } 
} 

Answer 1

不要忘记添加点击监听器，微调

spinner.setOnItemClickListener(this); 

Answer 2

你对你的按钮添加setOnClickListener（）。将setOnItemClickListener（）添加到您的微调器。

Answer 3

您需要把@Override设置为onItemSelected(...)和onNothingSelected(...)的功能。

确保您设置一个监听器上的微调： spinner.setOnItemClickListener(this);

编辑

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener { 
    MediaPlayer myMusic; 
    int paused; 


    public void play(View view) { 
     if (myMusic == null) { 
      myMusic = MediaPlayer.create(this, R.raw.fast_and_cold); 
      myMusic.start(); 


     } 
    } 


    public void stop(View view) { 
     myMusic.reset(); 
     myMusic = null; 
    } 



    String spinnerSelection = null; 
    Spinner spinner = null; 

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



     final List<String> spinnerContent = new ArrayList<>(); 
     spinnerContent.add("Black Metal"); 
     spinnerContent.add("Death Metal"); 
     spinnerContent.add("Thrash Metal"); 
     spinnerContent.add("Heavy Metal"); 



     ArrayAdapter<String> adapter = new ArrayAdapter<>(
      this, android.R.layout.simple_spinner_item, spinnerContent); 

     adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 


     spinner = (Spinner) findViewById(R.id.spinner); 
     spinner.setAdapter(adapter); 
     spinner.setOnItemSelectedListener(this); // add this line 



     Button button = (Button) findViewById(R.id.button); 
     button.setOnClickListener(new View.OnClickListener() { 





    } 

    @Override // add this line 
    public void onItemSelected(AdapterView<?>parent, View v, int position, long id) { 


      Toast.makeText(getBaseContext(),"Show your Devil Horns !!", Toast.LENGTH_SHORT).show(); 

    } 

    @Override // add this line 
    public void onNothingSelected(AdapterView<?> arg0) { 

    } 

}