Android „Can not Symbol lösen“ für setOnCheckedChangeListener und buttonView

Question

Ich versuche, einen Schalter zu schaffen, wenn sie aktiviert ist versteckt eine Taste button genannt, aber es gibt einen Fehler für SetOnCheckedChangeListener und buttonView die Cannot resolve symbol

package com.jordthedev.firstapplication; 

import android.content.Intent; 
import android.support.v7.app.AppCompatActivity; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.CompoundButton; 
import android.widget.ToggleButton; 

public class MainActivity extends AppCompatActivity { 
    int count = 0; 


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

    } 


    public void switchActivity(View v){ 
     startActivity(new Intent(MainActivity.this, SecondActivity.class)); 
    } 

    ToggleButton toggle = (ToggleButton) findViewById(R.id.toggleButton); 
    toggle.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { 
     public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { 
      if (isChecked) { 
       toggle.setVisibility(toggle.INVISIBLE); 
      } else { 
       toggle.setVisibility(toggle.VISIBLE); 
      } 
     } 
    }); 

} 

Answer 1

sagt Vielleicht Sie haben zu platzieren ToggleButton in onCreate() -Methode versuchen oben Code

package com.jordthedev.firstapplication; 

import android.content.Intent; 
import android.support.v7.app.AppCompatActivity; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.CompoundButton; 
import android.widget.ToggleButton; 

public class MainActivity extends AppCompatActivity { 
    int count = 0; 


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

     final ToggleButton toggle = (ToggleButton) findViewById(R.id.toggleButton); 
     toggle.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { 

      public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { 
       if (isChecked) { 
        toggle.setVisibility(toggle.INVISIBLE); 
       } else { 
        toggle.setVisibility(toggle.VISIBLE); 
       } 
      } 
     }); 
    } 


    public void switchActivity(View v){ 
     startActivity(new Intent(MainActivity.this, SecondActivity.class)); 
    } 



} 

Answer 2

Replace your OnCheckedChangeListener Code with this

ToggleButton toggle =(ToggleButton) findViewById(R.id.toggleButton); 
     toggle.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { 
      @Override 
      public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { 
       if (isChecked) { 
        toggle.setVisibility(toggle.INVISIBLE); 
       } else { 
        toggle.setVisibility(toggle.VISIBLE); 
       } 
      } 
     });