Question

我是一个新的android编码器。在这个项目中，没有红线，但当我尝试运行我的应用程序时，“不幸的是，”应用程序“已停止”弹出屏幕。虽然右边有几条黄色和紫色的线条。这是我的代码：

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;


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;
import android.widget.Button;

public class Translator extends ActionBarActivity {

    public ArrayAdapter<?> fromLanguageAdapter, toLanguageAdapter, englishAdapter,
            chineseAdapter, spanishAdapter;

    public Spinner fromLanguageSpinner = (Spinner) findViewById(R.id.spinner);
    public Spinner toLanguageSpinner = (Spinner) findViewById(R.id.spinner2);
    public Spinner phrases = (Spinner) findViewById(R.id.spinner3);
    public TextView answer = (TextView)findViewById(R.id.answer);
    public String[][] allPhrases = new String[][]{{"Hello","thank you","you are welcome","goodbye","i love you"},
            {"你好","谢谢","不用客气","再见","我爱你"},
            {"hola","gracias","bienvenido","adiós","te amo"}};
    public Button button = (Button) findViewById(R.id.button);


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

        fromLanguageAdapter = ArrayAdapter.createFromResource(this,R.array.fromLanguage,
                android.R.layout.simple_spinner_item);
        fromLanguageAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        fromLanguageSpinner.setAdapter(fromLanguageAdapter);
        fromLanguageSpinner.setOnItemSelectedListener(new languageListener());

        toLanguageAdapter =  ArrayAdapter.createFromResource(this,R.array.toLanguage,
                android.R.layout.simple_spinner_item);
        toLanguageAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        toLanguageSpinner.setAdapter(toLanguageAdapter);
        button.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                translate();
            }
        });
    }

    public class languageListener implements OnItemSelectedListener{
        @Override
        public void onItemSelected(AdapterView<?> parent, View v, int pos,
                                   long id) {

            //parent.getItemAtPosition(pos);

            if (pos==0)
                chooseEnglish(phrases);
            else if (pos==1)
                chooseChinese(phrases);
            else if (pos==2)
                chooseSpanish(phrases);
        }
        @Override
        public void onNothingSelected(AdapterView<?> arg0) {
        }
    }


    private void chooseEnglish(Spinner spinner){
        englishAdapter = ArrayAdapter.createFromResource(this,R.array.englishPhrases,
                android.R.layout.simple_spinner_item);
        englishAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(englishAdapter);
    }

    private void chooseChinese(Spinner spinner){
        chineseAdapter = ArrayAdapter.createFromResource(this,R.array.chinesePhrases,
    android.R.layout.simple_spinner_item);
        chineseAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner.setAdapter(chineseAdapter);
}

    private void chooseSpanish(Spinner spinner){
        spanishAdapter = ArrayAdapter.createFromResource(this,R.array.spanishPhrases,
                android.R.layout.simple_spinner_item);
        spanishAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(spanishAdapter);
    }

    void translate(){
        int toLanguagePosition = toLanguageSpinner.getSelectedItemPosition();
        int whichPhrase = phrases.getSelectedItemPosition();
        answer.setText(allPhrases[toLanguagePosition][whichPhrase]);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_translator, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

这是xml文件：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".Translator">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:text="From:"
        android:id="@+id/textView"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

    <Spinner
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/spinner"
        android:layout_below="@+id/textView"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:spinnerMode="dropdown"
        android:entries="@array/fromLanguage" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:text="To:"
        android:id="@+id/textView2"
        android:layout_below="@+id/spinner"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

    <Spinner
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/spinner2"
        android:layout_below="@+id/textView2"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:entries="@array/toLanguage" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:text="Phrases:"
        android:id="@+id/textView5"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_below="@+id/spinner2" />

    <Spinner
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/spinner3"
        android:layout_below="@+id/textView5"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Translate"
        android:id="@+id/button"
        android:clickable="true"
        android:onClick="buttonOnClick"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:text="Large Text"
        android:id="@+id/answer"
        android:layout_below="@+id/spinner3"
        android:layout_toLeftOf="@+id/button"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

</RelativeLayout>

Answer 1

您的错误很可能是因为您在setContentView调用之前尝试引用布局中的对象。尝试将其更改为：

public Spinner fromLanguageSpinner;
public Spinner toLanguageSpinner;
public Spinner phrases;
public TextView answer;
public String[][] allPhrases = new String[][]{{"Hello","thank you","you are welcome","goodbye","i love you"},
        {"你好","谢谢","不用客气","再见","我爱你"},
        {"hola","gracias","bienvenido","adiós","te amo"}};
public Button button;

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

fromLanguageSpinner = (Spinner) findViewById(R.id.spinner);
toLanguageSpinner = (Spinner) findViewById(R.id.spinner2);
phrases = (Spinner) findViewById(R.id.spinner3);
answer = (TextView)findViewById(R.id.answer);
button = (Button) findViewById(R.id.button);
....

不幸的是，“app”已停止

1 个答案: