xml中的代码应该没有问题,我是放在fragment_main.xml中的
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.loginstate.MainActivity$PlaceholderFragment" >
<EditText
android:id="@+id/et_username"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:hint="@string/input_username"
android:background="#ff33b5e5" />
<EditText
android:layout_marginTop="15dp"
android:layout_marginBottom="15dp"
android:id="@+id/et_password"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:hint="@string/input_password"
android:inputType="textPassword"
android:background="#ff33b5e5" />
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<CheckBox
android:layout_alignParentLeft="true"
android:id="@+id/cb_rem"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/rem_password" />
<Button
android:paddingRight="50dp"
android:paddingLeft="50dp"
android:layout_alignParentRight="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/login" />
/>
</RelativeLayout>
MainActivity.java代码如下
package com.itheima.login;
import java.security.PublicKey;
import java.util.Map;
import javax.security.auth.PrivateCredentialPermission;
import javax.security.auth.login.LoginException;
import com.itheima.login.util.UserInfoUtil;
import android.R;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener{
public EditText et_username;
private EditText et_password;
private CheckBox cb_rem;
private Button bt_login;
private Context mContext;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
mContext = this;
// a.找到相应控件
et_username = (EditText) findViewById(R.id.et_username);
et_password = (EditText) findViewById(R.id.et_password);
cb_rem = (CheckBox) findViewById(R.id.cb_rem);
bt_login = (Button) findViewById(R.id.bt_login);
// b.设置按钮的点击事件
bt_login.setOnClickListener(this);
//f.回显用户名密码
Map<String, String> map = UserInfoUtil.getUserInfo_android(mContext);
if(map != null){
String username = map.get("username");
String password = map.get("password");
et_username.setText(username);//设置用户名
et_password.setText(password);
cb_rem.setChecked(true);//设置复选框选中状态
}
}
private void login() {
// c.在onclick方法中,获取用户输入的用户名密码和是否记住密码
String username = et_username.getText().toString().trim();
String userpassword = et_password.getText().toString().trim();
boolean isrem = cb_rem.isChecked();
//d.判断用户名密码是否为空,不为空请求服务器(省略,默认请求成功)
if(username.isEmpty() || userpassword.isEmpty()){
Toast.makeText(mContext, "用户名密码不为空", Toast.LENGTH_SHORT).show();
return;
}
// e.判断是否记住密码,如果记住,将用户名密码保存本地。
if(isrem){
boolean result = UserInfoUtil.saveUserInfo_android(mContext, username, userpassword);
if(result){
Toast.makeText(mContext, "保存成功", Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(mContext, "保存失败", Toast.LENGTH_SHORT).show();
}
}else{
Toast.makeText(mContext, "不用保存", Toast.LENGTH_SHORT).show();
}
}
public void onClick(View v){
switch (v.getId()) {
case R.id.bt_login:
Login();
break;
default:
break;
}
}
}