Question

package org.example.mbtiapplication;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;

public class MBTITest extends Activity implements OnItemSelectedListener  {

    private Spinner firstSpinner;

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

        Spinner firstSpinner = (Spinner) findViewById(R.id.spinner1);
        // Create an ArrayAdapter using the string array and a default spinner layout
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
                R.array.spinnerarraybool, android.R.layout.simple_spinner_item);
        // Specify the layout to use when the list of choices appears
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        // Apply the adapter to the spinner
        firstSpinner.setAdapter(adapter);
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View v, int position,
            long id) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onNothingSelected(AdapterView<?> arg0) {
        // TODO Auto-generated method stub      
    } 
}

XML布局：

<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <TableRow
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:layout_width="120dp"
            android:layout_height="match_parent"
            android:layout_marginLeft="5dp"
            android:gravity="center_vertical"
            android:text="I like to go out more than staying home." />

        <Spinner
            android:id="@+id/spinner1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </TableRow>

    <TableRow
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:layout_width="120dp"
            android:layout_height="match_parent"
            android:layout_marginLeft="5dp"
            android:gravity="center_vertical"
            android:textSize="10.5dp"
            android:text="Sensing v Intuition" />

        <Spinner
            android:id="@+id/spinner2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </TableRow>
</TableLayout>

我是一名新的Android程序员，在使用Spinner方面遇到了麻烦，我尝试了多个教程但仍感到困惑。我想知道我的下一步是什么，据我所知，我已经用XML设置了我的微调器，用Java我已经确定了微调器，为所述微调器创建了一个ArrayAdapter，并指定了一些选项。我不确定我是否已经填充了微调器，或者如何使用微调器对象进行操作。我希望能够使用微调器对象选择三个选项之一，然后将该值保留在微调器内的textview内。

Answer 1

你快到了。正如您所看到的，onItemSelected将为您提供position参数，您可以使用此参数从适配器中检索对象，如getItemAtPosition(position)。

示例：

spinner.setOnItemSelectedListener(this);

...

public void onItemSelected(AdapterView<?> parent, View view, int pos,long id) {
    Toast.makeText(parent.getContext(), 
        "OnItemSelectedListener : " + parent.getItemAtPosition(pos).toString(),
        Toast.LENGTH_SHORT).show();
}

这将在屏幕上显示一条消息，其中所选项目由其toString（）方法打印。

Answer 2

如果你不想实现监听器，你可以直接在你想要的地方设置它（在设置适配器后调整你的微调器）：

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { switch (position) { case 0: Toast.makeText(parent.getContext(), "Spinner item 1!", Toast.LENGTH_SHORT).show(); break; case 1: Toast.makeText(parent.getContext(), "Spinner item 2!", Toast.LENGTH_SHORT).show(); break; case 2: Toast.makeText(parent.getContext(), "Spinner item 3!", Toast.LENGTH_SHORT).show(); break; } } @Override public void onNothingSelected(AdapterView<?> parent) { // sometimes you need nothing here } });

Answer 3

另一件事：如果布局中有多个微调器，则必须在onItemSlected（）方法中实现开关选择，以了解单击了哪个窗口小部件。像这样：

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
    switch (parent.getId()){
        case R.id.sp_alarmSelection:
            //Do something
            Toast.makeText(this, "Alarm Selected: " + parent.getSelectedItem().toString(), Toast.LENGTH_SHORT).show();
            break;
        case R.id.sp_optionSelection:
            //Do another thing 
            Toast.makeText(this, "Option Selected: " + parent.getSelectedItem().toString(), Toast.LENGTH_SHORT).show();
            break;
    }
}

Answer 4

约瑟夫： spinner.setOnItemSelectedListener(this) 应该在下面 Spinner firstSpinner = (Spinner) findViewById(R.id.spinner1); 在onCreate

Answer 5

spinner1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

               //check if spinner2 has a selected item and show the value in edittext

            }

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

               // sometimes you need nothing here
            }
        });

spinner2.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

               //check if spinner1 has a selected item and show the value in edittext


            }

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

               // sometimes you need nothing here
            }
        });

Answer 6

对于Kotlin和绑定，代码为：

binding.spinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener{
            override fun onNothingSelected(parent: AdapterView<*>?) {
            }

            override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
            }
        }

Answer 7

我认为这将使您受益试试这个，我用来更改应用程序中的语言

String[] districts;
Spinner sp;

......

 sp = (Spinner) findViewById(R.id.sp);
         districts = getResources().getStringArray(R.array.lang_array);
         ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item,districts);
         sp.setAdapter(adapter);
         sp.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
              @Override
             public void onItemSelected(AdapterView<?> arg0, View arg1, int position, long arg3) {
                  // TODO Auto-generated method stub
                  int index = arg0.getSelectedItemPosition();
                  Toast.makeText(getBaseContext(), "You select "+districts[index]+" id "+position, Toast.LENGTH_LONG).show();
                  switch(position){
                      case 0:
                          setLocal("fr");
                          //recreate();
                          break;
                      case 1:
                          setLocal("ar");
                          //recreate();
                          break;
                      case 2:
                          setLocal("en");
                          //recreate();
                          break;
                      default: //For all other cases, do this
                          setLocal("en");
                          //recreate();
                          break;
                  }
              }
             @Override
            public void onNothingSelected(AdapterView<?> arg0) {
                   // TODO Auto-generated method stub
                         }
        });

这是我的字符串数组

<string-array name="lang_array">
    <item>french</item>
    <item>arabic</item>
    <item>english</item>
</string-array>

如何在Android中使用onItemSelected？

7 个答案: