Android Spinner：在初始化过程中避免选中的调用

我用

微调器和
文本视图创建了一个Android应用程序。我想在TextView中显示微调器下拉列表中的选定项。我在
onCreate
方法中实现了微调器，因此当我运行程序时，它会在
TextView
中显示一个值（在从下拉列表中选择项目之前）

我只想在从下拉列表中选择一个项目后在文本视图中显示该值。我该怎么做

这是我的密码：

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

public class GPACal01Activity extends Activity implements OnItemSelectedListener {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Spinner spinner = (Spinner) findViewById(R.id.noOfSubjects);

        // Create an ArrayAdapter using the string array and a default spinner layout
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,R.array.noofsubjects_array, 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
        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(this);
    }

    public void onItemSelected(AdapterView<?> parent, View arg1, int pos,long id) {
        TextView textView = (TextView) findViewById(R.id.textView1);
        String str = (String) parent.getItemAtPosition(pos);
        textView.setText(str);
    }

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

    }
}

导入android.app.Activity；
导入android.os.Bundle；
导入android.view.view；
导入android.widget.AdapterView；
导入android.widget.AdapterView.OnItemSelectedListener；
导入android.widget.ArrayAdapter；
导入android.widget.Spinner；
导入android.widget.TextView；
公共类GPACal01Activity扩展活动实现了MSelectedListener{
/**在首次创建活动时调用*/
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.main）；
微调器微调器=（微调器）findViewById（R.id.noOfSubjects）；
//使用字符串数组和默认微调器布局创建ArrayAdapter
ArrayAdapter=ArrayAdapter.createFromResource（这是R.array.noofsubjects_数组，android.R.layout.simple_微调器_项）；
//指定显示选项列表时要使用的布局
setDropDownViewResource（android.R.layout.simple\u微调器\u下拉菜单\u项）；
//将适配器应用于微调器
旋转器。设置适配器（适配器）；
spinner.setOnItemSelectedListener（此）；
}
已选择公共位置（AdapterView父项、视图arg1、整数位置、长id）{
TextView TextView=（TextView）findViewById（R.id.textView1）；
String str=（String）parent.getItemAtPosition（pos）；
textView.setText（str）；
}
未选择公共无效（AdapterView arg0）{
//TODO自动生成的方法存根
}
}

所以第一次用任何整数值处理它

例如：
初始取
int check=0

public void onItemSelected(AdapterView<?> parent, View arg1, int pos,long id) {
   if(++check > 1) {
      TextView textView = (TextView) findViewById(R.id.textView1);
      String str = (String) parent.getItemAtPosition(pos);
      textView.setText(str);
   }
}

public void已选中（AdapterView父级、视图arg1、int pos、长id）{
如果（++检查>1）{
TextView TextView=（TextView）findViewById（R.id.textView1）；
String str=（String）parent.getItemAtPosition（pos）；
textView.setText（str）；
}
}

您可以使用布尔值，也可以通过检查当前和以前的位置来执行此操作
 启用多微调器的类似简单解决方案是，在第一次执行onItemSelected（…）时，将AdapterView放入集合-在Activities超类中，然后在执行之前检查AdapterView是否在集合中。这将启用超类中的一组方法，并支持多个AdapterViews和多个微调器

超类

private Collection<AdapterView> AdapterViewCollection = new ArrayList<AdapterView>();

   protected boolean firstTimeThrough(AdapterView parent) {
    boolean firstTimeThrough = ! AdapterViewCollection.contains(parent);
    if (firstTimeThrough) {
       AdapterViewCollection.add(parent);
     }
    return firstTimeThrough;
   }

private Collection AdapterViewCollection=new ArrayList（）；
受保护的布尔值首次通过（AdapterView父级）{
布尔值firstTimeThrough=！AdapterViewCollection.contains（父级）；
如果（首次通过）{
AdapterViewCollection.add（父级）；
}
第一次通过返回；
}

子类

public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
      if (! firstTimeThrough(parent)) {
        String value = safeString(parent.getItemAtPosition(pos).toString());
        String extraMessage = EXTRA_MESSAGE;
        Intent sharedPreferencesDisplayIntent = new         Intent(SharedPreferencesSelectionActivity.this,SharedPreferencesDisplayActivity.class);
    sharedPreferencesDisplayIntent.putExtra(extraMessage,value);
    startActivity(sharedPreferencesDisplayIntent);
  }
  // don't execute the above code if its the first time through
  // do to onItemSelected being called during view initialization.

public void已选择（AdapterView父视图、视图视图、整数位置、长id）{
如果（！firstTimeThrough（父级））{
字符串值=安全字符串（parent.getItemAtPosition（pos.toString（））；
字符串extraMessage=额外消息；
Intent sharedPreferencesDisplayIntent=新意图（SharedPreferenceSelectionActivity.this，SharedPreferencesDisplayActivity.class）；
sharedPreferencesDisplayIntent.putExtra（外部消息，值）；
startActivity（SharedReferencesDisplayIntent）；
}
//如果是第一次通过，请不要执行上述代码
//要在视图初始化期间调用所选的对象，请执行以下操作。

}我的解决方案：

protected boolean inhibit_spinner = true;


@Override
        public void onItemSelected(AdapterView<?> arg0, View arg1,
                int pos, long arg3) {

            if (inhibit_spinner) {
                inhibit_spinner = false;
            }else {

            if (getDataTask != null) getDataTask.cancel(true);
            updateData();
            }

        }

protected boolean inhibit\u微调器=true；
@凌驾
已选择公共视图（AdapterView arg0、视图arg1、，
内部位置，长arg3）{
if（禁止旋转器）{
抑制_微调器=假；
}否则{
如果（getDataTask！=null）getDataTask.cancel（true）；
更新数据（）；
}
}
您可以通过以下方式执行此操作：

AdapterView.OnItemSelectedListener listener = new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            //set the text of TextView
        }

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

        }
    });

yourSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            yourSpinner.setOnItemSelectedListener(listener);
        }

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

        }
    });

AdapterView.OnItemSelectedListener侦听器=新建AdapterView.OnItemSelectedListener（）{
@凌驾
已选择公共视图（AdapterView AdapterView、View视图、int i、long l）{
//设置TextView的文本
}
@凌驾
未选择公共无效（AdapterView AdapterView）{
}
});
yourSpinner.setOnItemSelectedListener（新的AdapterView.OnItemSelectedListener（）{
@凌驾
已选择公共视图（AdapterView AdapterView、View视图、int i、long l）{
yourSpinner.setOnItemSelectedListener（listener）；
}
@凌驾
未选择公共无效（AdapterView AdapterView）{
}
});

首先，我创建了一个侦听器，并将其归因于一个变量回调；然后我创建了第二个匿名侦听器，当第一次调用它时，它会更改侦听器
=]
从API级别3开始，您可以对带有布尔值的活动使用onUserInteraction（），以确定用户是否正在与设备交互


作为活动的一个字段，我有：

 private boolean userIsInteracting;

最后，我的微调器：

      mSpinnerView.setOnItemSelectedListener(new OnItemSelectedListener() {

           @Override
           public void onItemSelected(AdapterView<?> arg0, View view, int position, long arg3) {
                spinnerAdapter.setmPreviousSelectedIndex(position);
                if (userIsInteracting) {
                     updateGUI();
                }
           }

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

           }
      });

mSpinnerView.setOnItemSelectedListener（新的OnItemSelectedListener（）{
@凌驾
已选择公共位置（AdapterView arg0、视图、整型位置、长arg3）{
spinnerAdapter.setmPreviousSelectedIndex（位置）；
如果（用户交互）{
updateGUI（）；
}
}
@凌驾
未选择公共无效（AdapterView arg0）{
 private boolean userIsInteracting;

      mSpinnerView.setOnItemSelectedListener(new OnItemSelectedListener() {

           @Override
           public void onItemSelected(AdapterView<?> arg0, View view, int position, long arg3) {
                spinnerAdapter.setmPreviousSelectedIndex(position);
                if (userIsInteracting) {
                     updateGUI();
                }
           }

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

           }
      });

spinner.setAdapter(adapter);
spinner.setSelection(position);
spinner.setOnItemSelectedListener(listener);

public class MyClass extends <Activity/Fragment/Whatever> implements Spinner.OnItemSelectedListener {

    private void removeSpinnersListeners() {
        spn1.setOnItemSelectedListener(null);
        spn2.setOnItemSelectedListener(null);
    }

    private void setSpinnersListeners() {
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                spn1.setOnItemSelectedListener(MyClass.this);
                spn2.setOnItemSelectedListener(MyClass.this);
            }
        }, 1);
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        // Your code here
    }

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

    }
}

@Override
public boolean onTouch(final View view, final MotionEvent event) {
 view.setOnItemSelectedListener(this)
 return false;
}

spinner.setSelection(0,false)

public class SpinnerInteractionListener implements AdapterView.OnItemSelectedListener, View.OnTouchListener {

    boolean userSelect = false;

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        userSelect = true;
        return false;
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
        if (userSelect) { 
            userSelect = false;
            // Your selection handling code here
        }
    }

}

SpinnerInteractionListener listener = new SpinnerInteractionListener();
mSpinnerView.setOnTouchListener(listener);
mSpinnerView.setOnItemSelectedListener(listener);

Spinner.setAdapter();
Spinner.setSelected(false);  // must
Spinner.setSelection(0,true);  //must
Spinner.setonItemSelectedListener(this);

spinner.setSelection(Adapter.NO_SELECTION, true); //Add this line before setting listener
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

    }

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

    }
});

private boolean inispinner;

    spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            if (!inispinner) {
                inispinner = true;
                return;
            }
            //do your work here
        }

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

        }
    });

spinner.postDelayed(new Runnable() {
        @Override
        public void run() {
            addListeners();
        }
    }, 1000);.o

    spinner.setSelection(0, false);
    new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                spinner.setOnItemSelectedListener(listener);
            }, 500);

class SpinnerListener constructor(private val onItemSelected: (position: Int) -> Unit) : AdapterView.OnItemSelectedListener {

    private var selectionCount = 0

    override fun onNothingSelected(parent: AdapterView<*>?) {
        //no op
    }

    override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
        if (selectionCount++ > 1) {
           onItemSelected(position)
        }
    }
}

public void onItemSelected(AdapterView<?> parent, View arg1, int pos,long id) {

            if(Build.VERSION.SDK_INT >= 28){ //onItemSelected() doesn't seem to be called when listener is set on Api 28+
                check = 1;
            }

            if(++check > 1) {
                //Do your action here
            }
        }

private var mySpinnerHasBeenTapped = false

private fun initializeMySpinner() {

    my_hint_text_view.setOnClickListener {
        mySpinnerHasBeenTapped = true //turn flag to true
        my_spinner.performClick() //call spinner click
    }

    //Basic spinner setup stuff
    val myList = listOf("Leonardo", "Michelangelo", "Rafael", "Donatello")
    val dataAdapter: ArrayAdapter<String> = ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, myList)
    my_spinner.adapter = dataAdapter

    my_spinner.onItemSelectedListener = object : OnItemSelectedListener {

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

            if (mySpinnerHasBeenTapped) { //code below will only run after the user has clicked
                my_hint_text_view.visibility = View.GONE //once an item has been selected, hide the textView
                //Perform action here
            }
        }

        override fun onNothingSelected(parent: AdapterView<*>?) {
            //Do nothing
        }
    }
}

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

            <Spinner
                android:id="@+id/my_spinner"
                android:layout_width="match_parent"
                android:layout_height="35dp"
                android:layout_marginStart="10dp"
                android:layout_marginEnd="10dp"
                android:background="@drawable/bg_for_spinners"

                android:paddingStart="8dp"
                android:paddingEnd="30dp"
                android:singleLine="true" />

            <TextView
                android:id="@+id/my_hint_text_view"
                android:layout_width="match_parent"
                android:layout_height="35dp"                
                android:layout_marginStart="10dp"
                android:layout_marginEnd="10dp"
                android:background="@drawable/bg_for_spinners"

                android:paddingStart="8dp"
                android:paddingEnd="30dp"
                android:singleLine="true"
                android:gravity="center_vertical"
                android:text="*Select A Turtle"
                android:textColor="@color/green_ooze"
                android:textSize="16sp" />

        </FrameLayout>