android View.OnClickListener не запускается

Question

Я подаю в суд Android Studio 1.5.1 android api 23. Когда я нажимаю кнопку расчета, она не вызывает функцию public void onClick(View v).

Вот MainActivity.java:

   package gradescalculator.com.calculator.gradescalculator; 

      import android.app.AlertDialog; 
      import android.content.DialogInterface; 
      import android.content.Intent; 
      import android.os.Bundle; 
      import android.support.design.widget.FloatingActionButton; 
      import android.support.design.widget.Snackbar; 
      import android.support.v7.app.AppCompatActivity; 
      import android.support.v7.widget.Toolbar; 
      import android.view.Menu; 
      import android.view.MenuItem; 
      import android.view.View; 
      import android.widget.EditText; 

      public class MainActivity extends AppCompatActivity implements View.OnClickListener{ 

       EditText answer1; 
       EditText answer2; 
       EditText answer3; 
       private View calculate; 
       @Override 
       protected void onCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState); 
       setContentView(R.layout.activity_main); 
       Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
        // calculate =() findViewById(R.id.calculate); 
       calculate = findViewById(R.id.calculate); 
       calculate.setOnClickListener(this); 


       /* 
       calculate.setOnClickListener(new View.OnClickListener() { 
        public void onClick(View v) { 
        answer1 = (EditText) findViewById(R.id.answer1); 
        answer2 = (EditText) findViewById(R.id.answer2); 
        answer3 = (EditText) findViewById(R.id.answer3); 
        String answer1Value = answer1.getText().toString(); 
        String answer2Value = answer2.getText().toString(); 
        String answer3Value = answer3.getText().toString(); 

        Float answer1ValueFloat = new Float(answer1Value); 

        Float answer2ValueFloat = new Float(answer2Value); 

        Float answer3ValueFloat = new Float(answer3Value); 
        Float average = (answer1ValueFloat+answer2ValueFloat+answer3ValueFloat)/3; 
        Intent i = AnswerActivity.newIntent(MainActivity.this,average); 
        startActivityForResult(i,0); 

        } 
       }); 
       */ 
       setSupportActionBar(toolbar); 

       FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab); 
       fab.setOnClickListener(new View.OnClickListener() { 
        @Override 
        public void onClick(View view) { 
        Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG) 
         .setAction("Action", null).show(); 
        } 
       }); 
       new AlertDialog.Builder(this) 
        .setTitle(R.string.alert_title) 
        .setItems(R.array.languages, 
         new DialogInterface.OnClickListener() { 
          public void onClick(DialogInterface dialoginterface, int i) { 
          if (i == 1) { 
           setContentView(R.layout.activity_main); 

          } else { 
           setContentView(R.layout.activity_main_fr); 
          } 
          } 
         }) 
        .show(); 




       } 
       @Override 
       public void onClick(View v) { 
       answer1 = (EditText) findViewById(R.id.answer1); 
       answer2 = (EditText) findViewById(R.id.answer2); 
       answer3 = (EditText) findViewById(R.id.answer3); 
       String answer1Value = answer1.getText().toString(); 
       String answer2Value = answer2.getText().toString(); 
       String answer3Value = answer3.getText().toString(); 

       Float answer1ValueFloat = new Float(answer1Value); 

       Float answer2ValueFloat = new Float(answer2Value); 

       Float answer3ValueFloat = new Float(answer3Value); 
       Float average = (answer1ValueFloat+answer2ValueFloat+answer3ValueFloat)/3; 
       Intent i = AnswerActivity.newIntent(MainActivity.this,average); 
       startActivityForResult(i,0); 

       } 

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

Вот AnswerActivity.java:

   package gradescalculator.com.calculator.gradescalculator; 

      import android.content.Context; 
      import android.content.Intent; 
      import android.os.Bundle; 
      import android.support.v7.app.AppCompatActivity; 

      /** 
      * Created by aa on 3/6/2016. 
      */ 
      public class AnswerActivity extends AppCompatActivity { 
       private static final String CALCULATE_ANSWER="com.calculate.answer"; 

       protected void onCreate(Bundle saveInstanceState) { 
       super.onCreate(saveInstanceState); 
       setContentView(R.layout.activity_answer); 
       } 

       public static Intent newIntent(Context packageContext, Float average) { 
       Intent i = new Intent(packageContext, AnswerActivity.class); 
       i.putExtra(CALCULATE_ANSWER, average); 
       return i; 
       } 
      } 

Вот activity_answer.xml:

   <?xml version="1.0" encoding="utf-8"?> 
      <RelativeLayout 
       xmlns:android="http://schemas.android.com/apk/res/android" 
       xmlns:app="http://schemas.android.com/apk/res-auto" 
       xmlns:tools="http://schemas.android.com/tools" 
       android:layout_width="match_parent" 
       android:layout_height="match_parent" 
       android:paddingBottom="@dimen/activity_vertical_margin" 
       android:paddingLeft="@dimen/activity_horizontal_margin" 
       android:paddingRight="@dimen/activity_horizontal_margin" 
       android:paddingTop="@dimen/activity_vertical_margin" 
       app:layout_behavior="@string/appbar_scrolling_view_behavior" 
       tools:context="gradescalculator.com.calculator.gradescalculator.MainActivity" 
       tools:showIn="@layout/activity_main"> 

       <TableLayout xmlns:android="http://schemas.android.com/apk/res/android" 
        android:id="@+id/tableLayout1" 
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent"> 

       <TableRow 
        android:id="@+id/tableRow1" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grades_average"/> 
       </TableRow> 
       <TableRow 
        android:id="@+id/tableRow2" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 
        android:id="@+id/answerGrade1" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grade1"/> 

       </TableRow> 
       <TableRow 
        android:id="@+id/tableRow3" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 
        android:id="@+id/answerGrade2" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grade2"/> 

       </TableRow> 
       <TableRow 
        android:id="@+id/tableRow4" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 
        android:id="@+id/answerGrade3" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grade3"/> 

       </TableRow> 
       <TableRow 
        android:id="@+id/tableRow5" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grades_average"/> 
        <TextView 
        android:id="@+id/gradeAverage" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
         /> 
       </TableRow> 
       </TableLayout> 
      </RelativeLayout> 

Вот activity_main.xml:

   <?xml version="1.0" encoding="utf-8"?> 
      <android.support.design.widget.CoordinatorLayout 
       xmlns:android="http://schemas.android.com/apk/res/android" 
       xmlns:app="http://schemas.android.com/apk/res-auto" 
       xmlns:tools="http://schemas.android.com/tools" 
       android:layout_width="match_parent" 
       android:layout_height="match_parent" 
       android:fitsSystemWindows="true" 
       tools:context="gradescalculator.com.calculator.gradescalculator.MainActivity"> 

       <android.support.design.widget.AppBarLayout 
       android:layout_width="match_parent" 
       android:layout_height="wrap_content" 
       android:theme="@style/AppTheme.AppBarOverlay"> 

       <android.support.v7.widget.Toolbar 
        android:id="@+id/toolbar" 
        android:layout_width="match_parent" 
        android:layout_height="?attr/actionBarSize" 
        android:background="?attr/colorPrimary" 
        app:popupTheme="@style/AppTheme.PopupOverlay"/> 

       </android.support.design.widget.AppBarLayout> 

       <include layout="@layout/content_main"/> 

       <android.support.design.widget.FloatingActionButton 
       android:id="@+id/fab" 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:layout_gravity="bottom|end" 
       android:layout_margin="@dimen/fab_margin" 
       android:src="@android:drawable/ic_dialog_email"/> 

      </android.support.design.widget.CoordinatorLayout> 

Вот content_main.xml:

   <?xml version="1.0" encoding="utf-8"?> 
      <RelativeLayout 
       xmlns:android="http://schemas.android.com/apk/res/android" 
       xmlns:app="http://schemas.android.com/apk/res-auto" 
       xmlns:tools="http://schemas.android.com/tools" 
       android:layout_width="match_parent" 
       android:layout_height="match_parent" 
       android:paddingBottom="@dimen/activity_vertical_margin" 
       android:paddingLeft="@dimen/activity_horizontal_margin" 
       android:paddingRight="@dimen/activity_horizontal_margin" 
       android:paddingTop="@dimen/activity_vertical_margin" 
       app:layout_behavior="@string/appbar_scrolling_view_behavior" 
       tools:context="gradescalculator.com.calculator.gradescalculator.MainActivity" 
       tools:showIn="@layout/activity_main"> 

       <TableLayout xmlns:android="http://schemas.android.com/apk/res/android" 
        android:id="@+id/tableLayout1" 
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent"> 

       <TableRow 
        android:id="@+id/tableRow1" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/enter_grades"/> 
       </TableRow> 
       <TableRow 
        android:id="@+id/tableRow2" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grade1"/> 
        <EditText 
        android:id="@+id/answer1" 

        android:layout_height="wrap_content" 
        android:layout_width="wrap_content" 

        /> 
       </TableRow> 
       <TableRow 
        android:id="@+id/tableRow3" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <TextView 

        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grade2"/> 
        <EditText 
        android:id="@+id/answer2" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 

        /> 
       </TableRow> 
       <TableRow 
       android:id="@+id/tableRow4" 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:padding="5dip"> 
       <TextView 

        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/grade3"/> 
       <EditText 
        android:id="@+id/answer3" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 

        /> 
       </TableRow> 
       <TableRow 
        android:id="@+id/tableRow5" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="5dip"> 
        <Button android:id="@+id/calculate" 
         android:text="@string/calculate_grade" /> 

       </TableRow> 
       </TableLayout> 
      </RelativeLayout> 

Answer 1

Вычислить это идентификатор кнопки, так что вы должны инициализировать кнопку вместо зрения в классе Java. как это:

Button calculate =(Button)findViewById(R.id.calculate); 

Answer 2

//find your Button like this instead of view 

Button calculate =(Button)findViewById(R.id.calculate); 

      //use this below code for trigger button 

      @Override 
      public void onClick(View v) { 
      switch(v.getId()) 
       { 
        case R.id.calculate: 
          //write your code at here... it will work 
         break; 
       } 

      } 

Answer 3

Первое изменение типа вид '' в стоимость вашего MainActivity.java из 'View' на 'Button'. Вам нужно вывести ваш расчет в представление Button, чтобы установить OnClickListener. В принципе, заменить

private View calculate; 

с

private Button calculate; 

и

calculate = findViewById(R.id.calculate); 

с,

calculate = (Button) findViewById(R.id.calculate); 

Answer 4

удалить эту

private View calculate; 
calculate = findViewById(R.id.calculate); 

Заменить этот

private Button calculate; 
calculate =(Button) findViewById(R.id.calculate);