Question

我正在开发一款Android应用。我在一个活动中创建了登录表单，登录后切换到另一个活动。我正在尝试在切换活动时重置EditText字段，但在单击登录按钮时，它会在切换之前显示edittext框。它应该平滑切换，不显示文本框。在我的代码下面，我该怎么做才能做得更好？

package com.mtilab.blogspot.imtiapp;

    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.widget.TextView;
    import android.widget.EditText;
    import android.widget.Button;
    import android.view.View;
    import android.content.Intent;

    public class MainActivity extends AppCompatActivity {

        private TextView messageRef;
        private EditText usernameRef, passwordRef;
        private Button submitRef, signupRef;
         //user and pass for test case
        private String user = "admin", pass = "admin";

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


            messageRef = (TextView)findViewById(R.id.loginTV);
            usernameRef = (EditText)findViewById(R.id.usernameET);
            passwordRef = (EditText)findViewById(R.id.passwordET);
            submitRef = (Button)findViewById(R.id.loginB);
            signupRef = (Button)findViewById(R.id.registrationB);


           //submitref is ref of login button
            submitRef.setOnClickListener(
                    new View.OnClickListener(){
                        public void onClick(View vw){
                            if(usernameRef.getText().toString().equals(user) &&
                                  passwordRef.getText().toString().equals(pass)){

                  Intent userIntent = new   Intent(MainActivity.this, User.class);
                                startActivity(userIntent);

                                usernameRef.setText("");
                                passwordRef.setText("");
                                messageRef.setText("");
                            } else{
                                messageRef.setText("U R Not You!");

                                passwordRef.setText("");
                            }
                        }
                    }
            );
        }

        // way 2 , when login button pressed
        /*public void onClickLoginButton(View view) {

            messageRef = (TextView)findViewById(R.id.loginTV);
            usernameRef = (EditText)findViewById(R.id.usernameET);
            passwordRef = (EditText)findeViewById(R.id.passwordET);

            if(usernameRef.getText().toString().equals(user) &&
                    passwordRef.getText().toString().equals(pass)){

                Intent userIntent = new Intent(this, User.class);
                startActivity(userIntent);

                usernameRef.setText("");
                passwordRef.setText("");
                messageRef.setText("");
            }else{
                messageRef.setText("U R Not You!");

                passwordRef.setText("");
            }

        }*/

    }

Answer 1

您可以在开始下一个活动之前隐藏所有视图：

submitRef.setOnClickListener(
        new View.OnClickListener(){
             public void onClick(View vw){
                 if(usernameRef.getText().toString().equals(user) &&
                              passwordRef.getText().toString().equals(pass)){

                    usernameRef.setVisibility(View.INVISIBLE);
                    passwordRef.setVisibility(View.INVISIBLE);
                    messageRef.setVisibility(View.INVISIBLE);

                    // you might want to keep that
                    usernameRef.setText("");
                    passwordRef.setText("");
                    messageRef.setText("");

                    Intent userIntent = new   Intent(MainActivity.this, User.class);
                    startActivity(userIntent);

                 } else{
                    messageRef.setText("U R Not You!");

                    passwordRef.setText("");
                 }
            }
     }
);

使用View.INVISIBLE只会隐藏视图，但它仍会占用布局中的空间。如果您不想这样，请使用View.GONE。

有关详细信息，请参阅documentation。

切换活动（同时重置文本字段）不会顺利更改

1 个答案: