Question

我想使用微调器视图添加两个数字。在我的代码中有两个微调器。在我运行模拟器后，它只显示直接结果。它不显示微调控件，我无法选择这两个数字。请给出一个解决方案。提前致谢。代码

         package com.kk;
         import android.app.Activity;
         import android.os.Bundle;
         import android.view.View;
         import android.widget.AdapterView;
         import android.widget.ArrayAdapter;
         import android.widget.Spinner;
         import android.widget.AdapterView.OnItemSelectedListener;
         import android.widget.TextView;
         import android.R.id;

         public class TrckActivity extends Activity {
          /** Called when the activity is first created. */
          String[] a={"-select-","1","2"};
          String[] b={"-select-","2","4"};
          int first,second,f,s,c;
       public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        ArrayAdapter<String> a1= new ArrayAdapter<String>             (this,android.R.layout.simple_dropdown_item_1line,a);
    final Spinner sp1=(Spinner)findViewById(R.id.spinner1);
    sp1.setAdapter(a1);
    sp1.setOnItemSelectedListener(new OnItemSelectedListener(){

        @Override
        public void onItemSelected(AdapterView<?> arg0, View arg1,
                int arg2, long arg3) {
            first=sp1.getSelectedItemPosition();


        }

        @Override
        public void onNothingSelected(AdapterView<?> arg0) {


        }

    });
    ArrayAdapter<String> a2= new ArrayAdapter<String>(this,android.R.layout.simple_dropdown_item_1line,b);
    final Spinner sp2=(Spinner)findViewById(R.id.spinner1);
    sp2.setAdapter(a2);
    sp2.setOnItemSelectedListener(new OnItemSelectedListener(){

        @Override
        public void onItemSelected(AdapterView<?> arg0, View arg1,
                int arg2, long arg3) {
            second=sp2.getSelectedItemPosition();


        }

        @Override
        public void onNothingSelected(AdapterView<?> arg0) {


        }

    });

    if(first==1)
    {
        f=1;

    }
    else if(first==2)
    {
     f=2;
    }
    if(second==1)
    {
        s=2;
    }
    else if(second==2)
    {
        s=3;
    }
    c=f+s;
    TextView tv=new TextView(this);
    tv.setText(""+c);
    setContentView(tv);

}

}

Answer 1

这可能是因为一旦您的代码进入onCreate方法，最初就会调用微调器的“onItemSelected”方法。也许你必须保持标志值才能做到这一点。

这些链接可能会帮助您开始使用它，

Spinner onItemSelected called erroneously (without user action)

Spinner onItemSelected() executes when it is not suppose to

Answer 2

尝试交换

android.R.layout.simple_dropdown_item_1line

到

android.R.layout.simple_spinner_item

在android中使用微调器添加两个数字

2 个答案: