作为Android的初学者，我正在尝试创建示例应用 - 注册并登录。我正在使用Android Studio！
每当我点击注册按钮时，Snackbar会显示＆＃34;嘿，所有字段都是强制性的！＆＃34;尽管填满了所有的领域！
以下是为注册而编写的代码。
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Register extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
new AlertDialog.Builder(this)
.setTitle("Register Guidelines")
.setMessage("Hey!\nAll fields are mandatory!\n\nPassword must have minimum of 8 and maximum of 20 Characters in length.\n\nIt should contains atleast:\n1 CAPITAL LETTER\n1 small letter\n1 Number\nSpecial Characters among these:\n\t$ @ ! % * ? &\nDouble Click on Register to proceed!")
.setPositiveButton("Awesome!", null)
.show();
setupMessageButton();
}
public void setupMessageButton() {
final Button messageButton = (Button) findViewById(R.id.registerButton);
messageButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
final EditText name = (EditText) findViewById(R.id.editText1);
final EditText mobile = (EditText) findViewById(R.id.editText2);
final EditText email = (EditText) findViewById(R.id.editText3);
final EditText city = (EditText) findViewById(R.id.editText4);
final EditText password = (EditText) findViewById(R.id.editText5);
final EditText confirmPassword = (EditText) findViewById(R.id.editText6);
String nameS = name.getText().toString().trim();
String mobileS = mobile.getText().toString().trim();
String emailS = email.getText().toString().trim();
String cityS = city.getText().toString().trim();
String passwordS = password.getText().toString().trim();
String confirmPasswordS = confirmPassword.getText().toString().trim();
Intent intent;
if ((nameS.equals("")) || (mobileS.equals("")) || (emailS.equals("")) || (cityS.equals("")) || (passwordS.equals("")) || (confirmPasswordS.equals(""))) {
Snackbar.make(view, "Hey, all the fields are mandatory!", Snackbar.LENGTH_LONG).show();
}
if (nameS.equals(matcher))
{
Snackbar.make(view, "This is name.", Snackbar.LENGTH_LONG).show();
}
else if (isValidName(nameS) && isValidMobile(mobileS) && isValidEmail(emailS) && isValidCity(cityS) && isValidPassword(passwordS) && isValidPassword(confirmPasswordS)) {
if (confirmPasswordS.equals(passwordS)) {
Snackbar.make(view, "Credentials validated successfully.", Snackbar.LENGTH_LONG).show();
startActivity(new Intent(Register.this, SignIn.class));
}
}
}
}
);
}
Pattern pattern;
Matcher matcher;
public boolean isValidName(final String name) {
final String nameRegex = "^\\p{L}+(?: \\p{L}+)*$";
pattern = Pattern.compile(nameRegex);
matcher = pattern.matcher(name);
return matcher.matches();
}
public boolean isValidMobile(final String mobile) {
final String mobilePattern = "^[7-9][0-9]{10}$";
pattern = Pattern.compile(mobilePattern);
matcher = pattern.matcher(mobile);
return matcher.matches();
}
public boolean isValidEmail(final String email) {
final String emailRegex = "^[_A-Za-z0-9-\\\\+]+(\\\\.[_A-Za-z0-9-]+)*@"+"[A-Za-z0-9-]+(\\\\.[A-Za-z0-9]+)*(\\\\.[A-Za-z]{10,})$";
pattern = Pattern.compile(emailRegex);
matcher = pattern.matcher(email);
return matcher.matches();
}
public boolean isValidCity(final String city) {
final String cityRegex = "^\\p{L}+(?: \\p{L}+)*$";
pattern = Pattern.compile(cityRegex);
matcher = pattern.matcher(city);
return matcher.matches();
}
public boolean isValidPassword(final String password) {
final String passwordRegex = "^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)(?=.*[$@$!%*?&])[A-Za-z\\d$@$!%*?&]{8,20}";
pattern = Pattern.compile(passwordRegex);
matcher = pattern.matcher(password);
return matcher.matches();
}
}
XML：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:showIn="@layout/app_bar_register"
tools:context=".Register">
<ScrollView
android:id="@+id/scrollView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentTop="true">
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Register"
android:id="@+id/textView1"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_gravity="center_horizontal" />
<EditText
android:id="@+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:ems="12"
android:inputType="text"
android:hint="Name" >
</EditText>
<EditText
android:id="@+id/editText2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/editText1"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:ems="12"
android:inputType="phone"
android:hint="Mobile" />
<EditText
android:id="@+id/editText3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/editText2"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:ems="12"
android:inputType="textEmailAddress"
android:hint="Email" />
<EditText
android:id="@+id/editText4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/editText3"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:ems="12"
android:inputType="text"
android:hint="City" />
<EditText
android:id="@+id/editText5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/editText4"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:ems="12"
android:inputType="textPassword"
android:hint="Password" />
<EditText
android:id="@+id/editText6"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/editText5"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:ems="12"
android:inputType="textPassword"
android:hint="Confirm Password" />
<Button
android:id="@+id/registerButton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/editText6"
android:layout_centerHorizontal="true"
android:layout_marginTop="15dp"
android:textSize="20dp"
android:textColor="#5F3A7A"
android:text="Register" />
</LinearLayout>
</ScrollView>
答案 0 :(得分：1)
将以下代码移到onClick()方法：
final EditText name = (EditText) findViewById(R.id.editText1);
final EditText mobile = (EditText) findViewById(R.id.editText2);
final EditText email = (EditText) findViewById(R.id.editText3);
final EditText city = (EditText) findViewById(R.id.editText4);
final EditText password = (EditText) findViewById(R.id.editText5);
final EditText confirmPassword = (EditText) findViewById(R.id.editText6);
String nameS = name.getText().toString().trim();
String mobileS = mobile.getText().toString().trim();
String emailS = email.getText().toString().trim();
String cityS = city.getText().toString().trim();
String passwordS = password.getText().toString().trim();
String confirmPasswordS = confirmPassword.getText().toString().trim();
Intent intent;
目前发生的情况是上述代码运行一次，而不是每次按下按钮。因此nameS，mobileS等等始终为空。这就是它进入if区块的原因。严格来说，findViewById()代码不需要放在onClick()方法中。但是，您通过getText()获取文字的部分应该在onClick()方法
最好在onCreate()
setContentView()中的所有观看次数
答案 1 :(得分：1)
更改你的代码（将你的EditText声明移到clicklistener之外）：
public class Register extends AppCompatActivity {
EditText name;
EditText mobile;
EditText email;
EditText city;
EditText password;
EditText confirmPassword;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
new AlertDialog.Builder(this)
.setTitle("Register Guidelines")
.setMessage("Hey!\nAll fields are mandatory!\n\nPassword must have minimum of 8 and maximum of 20 Characters in length.\n\nIt should contains atleast:\n1 CAPITAL LETTER\n1 small letter\n1 Number\nSpecial Characters among these:\n\t$ @ ! % * ? &\nDouble Click on Register to proceed!")
.setPositiveButton("Awesome!", null)
.show();
name = (EditText) findViewById(R.id.editText1);
mobile = (EditText) findViewById(R.id.editText2);
email = (EditText) findViewById(R.id.editText3);
city = (EditText) findViewById(R.id.editText4);
password = (EditText) findViewById(R.id.editText5);
confirmPassword = (EditText) findViewById(R.id.editText6);
setupMessageButton();
}
public void setupMessageButton() {
final Button messageButton = (Button) findViewById(R.id.registerButton);
messageButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String nameS = name.getText().toString().trim();
String mobileS = mobile.getText().toString().trim();
String emailS = email.getText().toString().trim();
String cityS = city.getText().toString().trim();
String passwordS = password.getText().toString().trim();
String confirmPasswordS = confirmPassword.getText().toString().trim();
Intent intent;
if ((nameS.equals("")) || (mobileS.equals("")) || (emailS.equals("")) || (cityS.equals("")) || (passwordS.equals("")) || (confirmPasswordS.equals(""))) {
Snackbar.make(view, "Hey, all the fields are mandatory!", Snackbar.LENGTH_LONG).show();
}
if (nameS.equals(matcher))
{
Snackbar.make(view, "This is name.", Snackbar.LENGTH_LONG).show();
}
else if (isValidName(nameS) && isValidMobile(mobileS) && isValidEmail(emailS) && isValidCity(cityS) && isValidPassword(passwordS) && isValidPassword(confirmPasswordS)) {
if (confirmPasswordS.equals(passwordS)) {
Snackbar.make(view, "Credentials validated successfully.", Snackbar.LENGTH_LONG).show();
startActivity(new Intent(Register.this, SignIn.class));
}
}
}
}
);
}
...
}