安卓：类型不匹配：不能从EditText上转换为Boolean

Question

这里是我的代码
我尝试了解决方案，但它没有工作

package com.FF_studio.psp_rd_lite_1; 
    import android.app.Activity; 
    import android.os.Bundle; 
    import android.view.Menu; 
    import android.view.MenuItem; 
    import android.view.View; 
    import android.widget.EditText; 
    import android.widget.Toast; 

    public class LoginActivity extends Activity { 
     EditText urn,pwd; 

     @Override 
     protected void onCreate(Bundle savedInstanceState) { 
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.activity_login); 
     } 
     public void login(View v) { 

      urn = (EditText)findViewById(R.id.username); 
      pwd = (EditText)findViewById(R.id.password); 
      String site = ""; 
      String error = "用戶名稱或密碼錯誤,請重新輸入"; 
      String url = ""; 
      String ans = "admin"; 
      String ans1 = "rico1010"; 
      urn.getText().toString(); 
      pwd.getText().toString(); 

      if(urn = ans) //error occur here 
       url = ""; 
      else 
       Toast.makeText(this, error, Toast.LENGTH_SHORT).show(); 


     } 

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

Answer 1

几个问题在这里。

urn.getText().toString(); 

什么也没有做。你需要分配一个变量来利用它。

String urnString = urn.getText().toString(); 

其次，=是一个赋值运算符而不是比较运算符。您需要==进行比较。

三==is not the right way to compare Strings in Java你想.equals()