無法使用edittext.setText（「」）在android

Question

清除編輯文本我想清除或說重置editText，同時單擊清除表單按鈕。我無法清除editText框。這是我的完整代碼：

protected void onCreate(Bundle savedInstanceState) 
{ 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_contact_us); 

    et1 = (EditText) findViewById(R.id.editText1); //name 
    et3 = (EditText) findViewById(R.id.editText3); //email 
    et2 = (EditText) findViewById(R.id.editText2); //feedback 


    Button submit1 = (Button) findViewById(R.id.button1); 
    //submit1.setOnClickListener(this); 
    Button clear=(Button)findViewById(R.id.button2); 
    //clear.setOnClickListener(this); 

    submit1.setOnClickListener(new View.OnClickListener() 
    { 
     @Override 
     public void onClick(View view) 
     { 
      if(view==submit1) 
      { 
       if(et1.getText().toString().length()==0 || et2.getText().toString().length()==0 
         || et3.getText().toString().length()==0) 
       { 
        Toast t1=Toast.makeText(getApplicationContext(), "Please fill all the forms", 
          Toast.LENGTH_LONG); 
        t1.show(); 
       } 
       else 
       { 
        String email = "user@gmail.com"; 

        String sub1=spin.getSelectedItem().toString(); 
        String message = et2.getText().toString();//body 
        String name = et1.getText().toString(); 

        String from=et3.getText().toString(); 
        String emailPattern = "[a-zA-Z0-9._-]+@[a-z]+\\.+[a-z]+"; 

        if(from.matches(emailPattern)) 
        { 
         String body="Name :"+name+"\n"+"Email ID :"+ from+"\n"+"Feedback :"+message; 
         sendMail(email,sub1,from, body); 
        } 
        else 
        { 
         Toast.makeText(getApplicationContext(), "Invalid Email ID", Toast.LENGTH_SHORT).show(); 
         et3.setText(""); 
        } 
       } 
      } 
      else if(view==clear) 
       { 
        et1.setText(""); 
        et2.setText(""); 
        et3.setText(""); 
       } 
     } 
    }); 
} 

任何變化.. ??我要去哪裏錯了..？請幫我...

Answer 1

你忘了添加onClickListener清晰按鈕，出現更改如下面的代碼，

protected void onCreate(Bundle savedInstanceState) 
{ 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_contact_us); 

    et1 = (EditText) findViewById(R.id.editText1); //name 
    et3 = (EditText) findViewById(R.id.editText3); //email 
    et2 = (EditText) findViewById(R.id.editText2); //feedback 


    Button submit1 = (Button) findViewById(R.id.button1); 
    //submit1.setOnClickListener(this); 
    Button clear=(Button)findViewById(R.id.button2); 
    //clear.setOnClickListener(this); 

    submit1.setOnClickListener(new View.OnClickListener() 
    { 
     @Override 
     public void onClick(View view) 
     { 
      if(view==submit1) 
      { 
       if(et1.getText().toString().length()==0 || et2.getText().toString().length()==0 
         || et3.getText().toString().length()==0) 
       { 
        Toast t1=Toast.makeText(getApplicationContext(), "Please fill all the forms", 
          Toast.LENGTH_LONG); 
        t1.show(); 
       } 
       else 
       { 
        String email = "user@gmail.com"; 

        String sub1=spin.getSelectedItem().toString(); 
        String message = et2.getText().toString();//body 
        String name = et1.getText().toString(); 

        String from=et3.getText().toString(); 
        String emailPattern = "[a-zA-Z0-9._-]+@[a-z]+\\.+[a-z]+"; 

        if(from.matches(emailPattern)) 
        { 
         String body="Name :"+name+"\n"+"Email ID :"+ from+"\n"+"Feedback :"+message; 
         sendMail(email,sub1,from, body); 
        } 
        else 
        { 
         Toast.makeText(getApplicationContext(), "Invalid Email ID", Toast.LENGTH_SHORT).show(); 
         et3.setText(""); 
        } 
       } 
      } 
     } 
    }); 

    // Add this code 
    clear.setOnClickListener(new View.OnClickListener() 
    { 
      @Override 
      public void onClick(View view) 
      { 
       if(view==clear) 
       { 
        et1.setText(""); 
        et2.setText(""); 
        et3.setText(""); 
       } 
      } 
    }); 
} 

Answer 2

上點擊收聽實現清晰的按鈕： -

clear.setOnClickListener(new View.OnClickListener() 
    { 
     @Override 
     public void onClick(View view) 
     { 

        et1.setText(""); 
        et2.setText(""); 
        et3.setText(""); 

     } 
    }); 

Answer 3

試試這個，

EditText et1; 
et1.setText(null);