Simple Android two spinner and submit example

问题:

Very new to Android development.

I have been referencing this StackOverflow thread: Android: two Spinner onItemSelected(), but thus far have been running into issues with trying to build a simple program with two spinners and a submit button. The simple program I am trying to develop captures whatever is selected in both Spinners and on submit, does 'something'.

If I use the below onItemSelectedListener, how do I implement an onClick Listener that captures whatever is currently selected in both spinners? Does the same 'View' get passed to the 'onClick' listener or no?

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

    Spinner spinner = (Spinner) parent;
    if(spinner.getId() == R.id.spinner1)
    {
    //do this                    
    }
    else if(spinner.getId() == R.id.spinner2)
    {
   //do this
    }

}

Thanks so much for your help!

EDIT

After implmenting Nolly J's suggested code, I am almost there. It seems like the spinnerFromValue and spinnerToValue strings are still not being set. I have:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    distValue = (EditText) findViewById(R.id.distValue);
    distResult = (EditText) findViewById(R.id.distResult);


    this.arraySpinner = new String[]{"Miles", "Kilometers", "Meters", "Feet", "Inches", "Centimeters"};
    Spinner spinnerFrom = (Spinner) findViewById(R.id.spinnerFrom);
    Spinner spinnerTo = (Spinner) findViewById(R.id.spinnerTo);

    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, arraySpinner);
    spinnerFrom.setAdapter(adapter);
    spinnerTo.setAdapter(adapter);

    buttonConvert = (Button) findViewById(R.id.buttonConvert);
    buttonConvert.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            // use the two variables to do what you want.
            // Example
            distResult.setText(spinnerFromValue + spinnerToValue);

        }
    });



}

@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

}

public class SpinnerActivity extends Activity implements AdapterView.OnItemSelectedListener {

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

        Spinner spinner = (Spinner) parent;

        spinnerFromValue = parent.getSelectedItem().toString();
        spinnerToValue = parent.getSelectedItem().toString();
        if(spinner.getId() == R.id.spinnerFrom){
            //do this
            spinnerFromValue = parent.getSelectedItem().toString();
        }
        else if(spinner.getId() == R.id.spinnerTo){
            //do this
            spinnerToValue = parent.getSelectedItem().toString();
        }
    }

    public void onNothingSelected(AdapterView<?> parent) {
        // Another interface callback
    }

}

Any ideas?

回答1:

You can have two global variables that will hold the select items in the spinners.

private String spinnerOneValue;
private String spinnerTwoValue;

How to get the selected values of the Spinner widget

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

    Spinner spinner = (Spinner) parent;
    if(spinner.getId() == R.id.spinner1){
         //do this  
         spinnerOneValue = spinnerOne.getSelectedItem().toString();                  
    }
    else if(spinner.getId() == R.id.spinner2){
        //do this
        spinnerTwoValue = spinnerTwo.getSelectedItem().toString(); 
    }

}

Add a button and attached a click event

  button.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
            // use the two variables to do what you want.
            // Example
            mTextView.setText(spinnerOneValue + spinnerTwoValue);

        }
    });

To put everything together, try this. Remember to add a TextView in your layout file if you need it

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

public class SpinnerActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {

private String firstSpinnerValue = "";
private String secondSpinnerValue = "";

private EditText distValue;
private EditText distResult;

private Button buttonConvert;

private String[] arraySpinner;

private TextView disPlaySpinnerValues;

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

    distValue = (EditText) findViewById(R.id.distValue);
    distResult = (EditText) findViewById(R.id.distResult);

    disPlaySpinnerValues = (TextView)findViewById(R.id.display);


    this.arraySpinner = new String[]{"Miles", "Kilometers", "Meters", "Feet", "Inches", "Centimeters"};
    Spinner spinnerFrom = (Spinner) findViewById(R.id.spinnerFrom);
    Spinner spinnerTo = (Spinner) findViewById(R.id.spinnerTo);

    spinnerFrom.setOnItemSelectedListener(this);  
    spinnerTo.setOnItemSelectedListener(this);    

    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, arraySpinner);
    spinnerFrom.setAdapter(adapter);
    spinnerTo.setAdapter(adapter);

    buttonConvert = (Button) findViewById(R.id.buttonConvert);
    buttonConvert.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            disPlaySpinnerValues.setText(firstSpinnerValue + secondSpinnerValue);
        }
    });
}

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
    Spinner spinner = (Spinner) parent;

    if(spinner.getId() == R.id.spinnerFrom){
        //do this
        firstSpinnerValue = parent.getSelectedItem().toString();
    }
    else if(spinner.getId() == R.id.spinnerTo){
        //do this
        secondSpinnerValue = parent.getSelectedItem().toString();
    }
}

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

 }
}