android - 如何使用微调器

Question

我对安卓很陌生。I want to use 2 spinners in my application, one shows the countries list, when any country is selected the other spinner should show the list of cities of that country. when city is selected some action is performed. 请帮我一些示例代码。期待中的感谢

Answer 1

这是我们可以用来向 spinner2 wrt 添加选项到 spinner 1 的东西。

public class Activity extends Activity implements View.OnClickListener
{
    private Spinner spinner0, spinner1, spinner2, spinner3;
    private Button submit, cancel;

    private String country[], state[], city[], area[];

    Australia aus = new Australia();

    Object object;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        spinner0 = (Spinner)findViewById(R.id.spinnerCountry);
        spinner1 = (Spinner)findViewById(R.id.spinnerQ1);
        spinner2 = (Spinner)findViewById(R.id.spinnerQ2);
        spinner3 = (Spinner)findViewById(R.id.spinnerQ3);

        submit = (Button)findViewById(R.id.btnSubmit);
        cancel = (Button)findViewById(R.id.btnCancel);

        submit.setOnClickListener(this);
        cancel.setOnClickListener(this);

        country = new String[] {"Select Country", "Australia", "USA", "UK", "New Zealand", "EU", "Europe", "China", "Hong Kong",
                                "India", "Malaysia", "Canada", "International", "Asia", "Africa"};


        ArrayAdapter<String> adapter0 = new ArrayAdapter<String>(Activity.this, android.R.layout.simple_spinner_item, country);
        adapter0.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
        spinner0.setAdapter(adapter0);
        Log.i("AAA","spinner0");

        spinner0.setOnItemSelectedListener(new OnItemSelectedListener()
        {           
            @Override
            public void onItemSelected(AdapterView<?> arg0, View view1, int pos, long id)
            {
                Log.i("AAA","OnItemSelected");
                int loc;
                loc = pos;

                switch (loc)
                {
                case 1:

                    state = aus.getState();
                    object = aus;

                    Log.i("AAA","ArrayAdapter1");                   
                    ArrayAdapter<String> adapter1 = new ArrayAdapter<String>(Activity.this, android.R.layout.simple_spinner_item, state);
                    adapter1.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
                    spinner1.setAdapter(adapter1);          Log.i("AAA","spinner1");
                    break;

                default:
                    Log.i("AAA","default 0");
                    break;
                }                               
            }       

            @Override
            public void onNothingSelected(AdapterView<?> arg1)
            {
                Log.i("AAA","Nothing S0");

            }
        });

       spinner1.setOnItemSelectedListener(new OnItemSelectedListener()
       {
            @Override
            public void onItemSelected(AdapterView<?> arg0, View view1, int pos, long id) 
            {
                Log.i("AAA","OnItemSelected S1");
                int loc = pos;
                switch(loc)
                {
                    case 1:
                        Log.i("AAA","Australia");
                        if(object.equals(aus))
                        {
                            city = aus.getType(loc);
                        }
                        else
                        {
                            break;
                        }


                        ArrayAdapter<String> adapter = new ArrayAdapter<String>(Activity.this, android.R.layout.simple_spinner_item, city);
                        adapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
                        spinner2.setAdapter(adapter);           Log.i("AAA","spinner2");
                        break;

                    default:
                            Log.i("AAA", "default 1");
                        break;

                }
            }
            @Override
            public void onNothingSelected(AdapterView<?> arg0)
            {
                Log.i("AAA","Nothing S1");              
            }

        }); 

       spinner2.setOnItemSelectedListener(new OnItemSelectedListener()
       {

        @Override
        public void onItemSelected(AdapterView<?> arg0, View arg1, int pos, long id)
        {
            int loc = pos;
            switch (loc)
            {
            case 1:
                if(object.equals(aus))
                {
                    area = aus.getTitle(loc);
                }

                ArrayAdapter<String> adapter = new ArrayAdapter<String>(Activity.this, android.R.layout.simple_spinner_item, area);
                adapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
                spinner3.setAdapter(adapter);           Log.i("","spinner3");               
                break;

            default:
                break;
            }

        }

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

    }// on-create


    @Override
    public void onClick(View v)
    {
        switch (v.getId())
        {
        case R.id.btnSubmit:

            break;

        case R.id.btnCancel:
            finish();
            break;

        default:
            break;
        }       
    }   
}

如果您觉得这很有用，请放弃投票，以便其他人可以轻松找到一个好的答案。

对于每个国家，您必须为其创建一个类，只需添加州、城市和地区。这样它就不会在单个页面上变成一个网格。

玩得开心。

问候，

哈普斯。

Answer 2

检查以下示例：

https://developer.android.com/guide/tutorials/views/hello-spinner.html
http://www.designerandroid.com/?cat=4

Answer 3

这是一个示例代码，描述了微调器的用法和选择微调器项时执行的操作

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

public class MainActivity extends Activity {

    Spinner spin;
    String spin_val;
    String[] gender = { "Male", "Female" };//array of strings used to populate the spinner
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);//setting layout
        spin = (Spinner) findViewById(R.id.spinner_id);//fetching view's id
        //Register a callback to be invoked when an item in this AdapterView has been selected
        spin.setOnItemSelectedListener(new OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1,
                    int position, long id) { 
                // TODO Auto-generated method stub
                spin_val = gender[position];//saving the value selected


            }

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

            }

        });
      //setting array adaptors to spinners 
      //ArrayAdapter is a BaseAdapter that is backed by an array of arbitrary objects
        ArrayAdapter<String> spin_adapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item, gender);

        // setting adapteers to spinners
        spin.setAdapter(spin_adapter);
    }


}

要将值列表添加到微调器，您需要在 Activity 中指定一个 SpinnerAdapter，它扩展了 Adapter 类。微调器适配器允许定义两个不同的视图：一个显示微调器本身中的数据，一个显示按下微调器时下拉列表中的数据。您也可以下载并参考完整的spinner_demo示例项目以更好地理解。

Answer 4

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    spinner = (Spinner)findViewById(R.id.spinner);
    list = new ArrayList<String>();
    list.add("Select your Favorite Color");
    list.add("Blue");
    list.add("White");
    list.add("Red");
    list.add("Green");
    list.add("Black");
    list.add("Yellow");
    list.add("Pink");
    list.add("Orange");
    SpinnerAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,list){
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
           View v = super.getView(position, convertView, parent);
            // set the textColor you want
            return v;
        }

        @Override
        public View getDropDownView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
            View v = super.getDropDownView(position, convertView, parent);
// Set the BackgroundColor
            return v;
        }
    };
    SpinnerAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner.setAdapter(SpinnerAdapter);
    spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            String state = adapterView.getItemAtPosition(i).toString();
        }

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

        }
    });
}

}