Question

我在Android中正在做一个项目，我想在同一个活动中添加第二个微调器。它应该独立于第一个微调器。

我该怎么办？

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import static android.R.layout.simple_dropdown_item_1line;
import static android.R.layout.simple_spinner_item;

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {
    Spinner spinner;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        spinner=(Spinner) findViewById(R.id.spinner);
        ArrayAdapter adapter=ArrayAdapter.createFromResource(this, R.array.field_name, android.R.layout.simple_spinner_item);
        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(this);

    }


    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        TextView myText= (TextView) view;
        Toast.makeText(this,"You have Selected "+ myText.getText(),Toast.LENGTH_SHORT).show();
    }

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

    }



}

接下来需要做什么？

Answer 1

创建另一个微调器spinner2

然后重复你的代码：

 spinner2=(Spinner) findViewById(R.id.spinner2);
 ArrayAdapter adapter2=ArrayAdapter.createFromResource(this, R.array.field_name, android.R.layout.simple_spinner_item);
    spinner2.setAdapter(adapter2);
    spinner2.setOnItemSelectedListener(this);

不要忘记在 .xml 中创建另一个微调器，即spinner2。

完整的代码：

 public class MainActivity extends AppCompatActivity  {
        Spinner spinner,spinner2;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            spinner=(Spinner) findViewById(R.id.spinner);
            ArrayAdapter adapter=ArrayAdapter.createFromResource(this,     R.array.field_name, android.R.layout.simple_spinner_item);
            spinner.setAdapter(adapter);


             spinner2=(Spinner) findViewById(R.id.spinner2);
             ArrayAdapter adapter2=ArrayAdapter.createFromResource(this, R.array.field_name, android.R.layout.simple_spinner_item);
            spinner2.setAdapter(adapter2);


    spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
            // your code here
        }

        @Override
        public void onNothingSelected(AdapterView<?> parentView) {
            // your code here
        }

    });


    spinner2.setOnItemSelectedListener(new OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parentView, View     selectedItemView, int position, long id) {
            // your code here
        }

        @Override
        public void onNothingSelected(AdapterView<?> parentView) {
            // your code here
        }

    });

     }

    }

Answer 2

将另一个Spinner添加到XML中，并以相同的方式声明并初始化它。

Spinner spinner1 , spinner2;

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

        spinner1=(Spinner) findViewById(R.id.spinner1);
        spinner2=(Spinner) findViewById(R.id.spinner2);
        ArrayAdapter adapter1=ArrayAdapter.createFromResource(this, R.array.field_name, android.R.layout.simple_spinner_item);
        ArrayAdapter adapter2=ArrayAdapter.createFromResource(this, R.array.field_name, android.R.layout.simple_spinner2_item);
        spinner1.setAdapter(adapter);
        spinner2.setAdapter(adapter2);
        spinner1.setOnItemSelectedListener(this);
        spinner2.setOnItemSelectedListener(this);

        }

您不需要为同一布局中的每个微调器重写单独的方法。以下内容适用于spinner1和spinner2。您可以执行检查以了解选择了哪个微调器的项目

 @Override
    public void onItemSelected(AdapterView<?> parentView, View view, int position, long id) {
      Spinner spinner = (Spinner) parentView;
     if(spinner.getId() == R.id.spinner1){
               //do this                
        }
     else if(spinner.getId() == R.id.spinner2){
              //do this
        }
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
    // your code here
  }

请记住，对于一个微调器，OnItemSelectedListener事件将执行两次 -

Spinner初始化
用户手动选择任何项目

您可以使用标志变量来区分这两者。

在同一活动中添加第二个微调器

2 个答案: