Android开发――记账App开发项目分享（一）之用户登录

一、题外话：

本人java基础很一般，学java的时候就写了个notepad的demo，为了顺应时代的发展在去年10月份开始学习android，到现在中间渐渐续续的持续了将近5个月，刚开始我也是下了一堆android的视频，很可惜只看了前2章老罗的视频，工作的人了没那么大的耐心和时间慢慢看下去，依照视频和网上资料把android的开发环境搭起来了，android SDK+eclipse ，中间也尝试了使用android studio ，但是一旦出了问题，查找的资料相对Eclipse要少很多，所以对于初学者建议还是用Eclipse~没有多少基础，也不想慢慢看视频，直接就进入实操，期间困难在所难免，但坚持下来收获也是非常明显的了，现在我就分享下整个开发过程，当然也会包括代码分享~让其他正在步入android门槛的童鞋可以有个借鉴，减少弯路~

二、进入正题：

记账应用的开发涉及绝大多数android的UI和sqlite数据库等操作，很适合作为初学者练手，下面是我最开始的设计思路：

后面在开发过程中有修改，还是直接来干货，我就按照我的开发顺序来依次介绍，首先是登录界面的功能：UI中运用了LinearLayout+RelativeLayout组合布局的使用，期间有各种属性的使用，写一个这样的界面就可以了解很多UI的属性了。

效果如下图：

xml源码：

 <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" 
    android:background="#FFFFFF">
    <ImageView
        android:layout_width="120dp"
        android:layout_height="120dp"
        android:layout_gravity="center"
        android:background="@drawable/logo1" >
    </ImageView>
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:layout_marginTop="8dp"
            android:gravity="center"
            android:text="欢迎登录记账星"
            android:textColor="#57647D"
            android:textSize="20sp"
            android:textStyle="bold" >
        </TextView>
    </LinearLayout>
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >
        <LinearLayout
            android:layout_width="260dp"
            android:layout_height="100dp"
            android:layout_gravity="center_horizontal"
            android:layout_marginTop="8dp"
            android:background="@drawable/userinfo_border"
            android:orientation="vertical" >
            <AutoCompleteTextView
                android:id="@+id/username"
                android:layout_width="250dp"
                android:layout_height="45dp"
                android:layout_gravity="center_horizontal"
                android:layout_marginTop="1dp"
                android:background="#FFFFFF"
                android:drawableLeft="@drawable/user"
                android:drawablePadding="10dp"
                android:hint="请输入您的用户名"
                android:textColor="#3D3D3D"
                android:textColorHint="#A3B1CA"
                android:textSize="15sp" >
            </AutoCompleteTextView>
            <View
                android:layout_width="match_parent"
                android:layout_height="0.2dp"
                android:layout_marginTop="4dp"
                android:background="#F2F2F2" >
            </View>
            <EditText
                android:id="@+id/pwd"
                android:layout_width="250dp"
                android:layout_height="45dp"
                android:layout_gravity="center_horizontal"
                android:background="#FFFFFF"
                android:drawableLeft="@drawable/password"
                android:drawablePadding="10dp"
                android:hint="请输入您的密码  "
                android:inputType="textPassword"
                android:textColorHint="#A3B1CA"
                android:textSize="15sp" >
            </EditText>
        </LinearLayout>
        <Button
            android:id="@+id/btnLogin"
            android:layout_width="260dp"
            android:layout_height="48dp"
            android:layout_gravity="center_horizontal"
            android:layout_marginTop="20dp"
            android:background="@drawable/normalbtnstyle"
            android:gravity="center"
            android:text="登  录"
            android:textColor="#FFFFFF"
            android:textSize="20sp"
            android:textStyle="bold" >
        </Button>
  <LinearLayout
         android:layout_width="260dp"
         android:layout_height="wrap_content"
         android:orientation="horizontal"
         android:layout_gravity="center"
         android:gravity="center"
         android:layout_marginTop="10dp">"
        <CheckBox
            android:id="@+id/cbRememberPwd"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:layout_weight="1"
            android:checked="false"
            android:text="记住密码"
            android:textColor="#5E6A81"
            android:textSize="15sp" />
            
        <Button
            android:id="@+id/btnForgetPwd"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="#FFFFFF"
            android:gravity="right"
            android:layout_weight="1"
            android:textColor="@drawable/btn_forgetpwd_color"
            android:textSize="15sp" 
            android:text="忘记密码？"/>
        </LinearLayout>
    </LinearLayout>
    <RelativeLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="40dp"
        android:gravity="center"
        android:orientation="vertical" >
        <TextView
            android:id="@+id/zhucexinxi"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_marginBottom="5dp"
            android:gravity="center"
            android:text="啊，还没有账户？马上点击 "
            android:textColor="#5E6A81"
            android:textSize="14sp" >
"
        </TextView>
        <TextView
            android:id="@+id/txtRegisterLink"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_marginBottom="5dp"
            android:layout_toRightOf="@+id/zhucexinxi"
            android:textSize="15sp"
            android:textStyle="bold" >
        </TextView>
    </RelativeLayout>
</LinearLayout>

程序代码：

由于这里面程序代码无非就是一些判断控制，这里就只上传保存按钮的代码……

btnlogin.setOnClickListener(new OnClickListener() {
   
   @Override
   public void onClick(View v) {
    if (uname!="" && uname!=null) {
     if (rememberPwd.equals("true")) {
      if (evUsername.getText().toString().trim().length()>0) {
       if (evUsername.getText().toString().trim().equals(uname)) {
        Toast.makeText(Login.this,"登录成功",Toast.LENGTH_SHORT).show();
        Intent intent =new Intent(Login.this,MainActivity.class);
        startActivity(intent);
        intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
        finish();
        ((NotifyApplication)getApplication()).intLoginStatus=1;//登录激活
        ((NotifyApplication)getApplication()).strUsername = uname;
       }else {
        Toast.makeText(Login.this,"用户名不正确",Toast.LENGTH_SHORT).show();
        evUsername.setText("");
        evUsername.requestFocus();
       }
      }else {
       Toast.makeText(Login.this,"用户名不能为空",Toast.LENGTH_SHORT).show();
       evUsername.requestFocus();
      }
     }else {
      if (evUsername.getText().toString().trim().length()>0) {
       if (evPwd.getText().toString().trim().length()>5) {
        if (evUsername.getText().toString().trim().equals(uname)) {
         if (evPwd.getText().toString().equals(pwd)) {
          Toast.makeText(Login.this,"登录成功",Toast.LENGTH_SHORT).show();
          Intent intent =new Intent(Login.this,MainActivity.class);
          startActivity(intent);
          intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
          finish();
          ((NotifyApplication)getApplication()).intLoginStatus=1;//登录激活
          ((NotifyApplication)getApplication()).strUsername = uname;
         }else {
          Toast.makeText(Login.this,"密码不正确",Toast.LENGTH_SHORT).show();
          evPwd.setText("");
          evPwd.requestFocus();
         }
        }else {
         Toast.makeText(Login.this,"用户名不正确",Toast.LENGTH_SHORT).show();
         evUsername.setText("");
         evUsername.requestFocus();
        }
       }else {
        Toast.makeText(Login.this,"密码长度至少为6",Toast.LENGTH_SHORT).show();
        evPwd.setText("");
        evPwd.requestFocus();
       }
      }else {
       Toast.makeText(Login.this,"用户名不能为空",Toast.LENGTH_SHORT).show();
       evUsername.requestFocus();
      }
     }
    }else {
     Toast.makeText(Login.this,"您还未注册，请点击下方注册",Toast.LENGTH_SHORT).show();
    }
    
   }
  });

在现在看来这个页面有难度的地方，就是“注册”标签的点击链接功能的实现，需要用到SpannableString 这个类，实现该处具体源码如下：

txtRegisterLink=(TextView)findViewById(R.id.txtRegisterLink);
  
  String str2="注册";
  SpannableString spans = new SpannableString(str2); 
  //点击文本链接事件
  spans.setSpan(new ClickableSpan() {
   @Override  
   public void onClick(View widget) {
       if (uname==null || uname=="") {
        Intent intent = new Intent(Login.this, Register.class);
                 startActivity(intent);
                 finish();
       }else{
        Toast.makeText(Login.this,"您已注册，不能重复注册",Toast.LENGTH_SHORT).show();
       } 
              }
           }, 0, str2.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
  
  txtRegisterLink.setText(spans);

 

接着写~~~

有用户登录界面，当然就需要用户注册界面了，上面也有贴出在用户登录界面通过link调转到注册界面的代码，下面就直接说注册界面的功能点：

效果图：

注册界面的xml代码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#FFFFFF"
    android:layout_gravity="center_horizontal"    
    android:orientation="vertical" >
    <LinearLayout
        android:layout_width="260dp"
        android:layout_height="220dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="40dp"
        android:background="@drawable/userinfo_border"
        android:orientation="vertical" >
        <EditText
            android:id="@+id/username"
            android:layout_width="250dp"
            android:layout_height="45dp"
            android:layout_gravity="center_horizontal"
            android:layout_marginTop="1dp"
            android:background="#FFFFFF"
            android:drawableLeft="@drawable/user"
            android:drawablePadding="6sp"
            android:hint="请输入您的用户名"
            android:textColor="#3D3D3D"
            android:textColorHint="#A3B1CA"
            android:textSize="15sp" >
        </EditText>
        <View
            android:layout_width="match_parent"
            android:layout_height="0.2dp"
            android:layout_marginTop="4dp"
            android:background="#F2F2F2" >
        </View>
        <EditText
            android:id="@+id/RegPwd"
            android:layout_width="250dp"
            android:layout_height="45dp"
            android:layout_gravity="center_horizontal"
            android:background="#FFFFFF"
            android:drawableLeft="@drawable/password"
            android:drawablePadding="6sp"
            android:hint="请输入您的密码  "
            android:inputType="textPassword"
            android:textColorHint="#A3B1CA"
            android:textSize="15sp" >
        </EditText>
        <View
            android:layout_width="match_parent"
            android:layout_height="0.2dp"
            android:layout_marginTop="4dp"
            android:background="#F2F2F2" >
        </View>
        <EditText
            android:id="@+id/RegPwdAgain"
            android:layout_width="250dp"
            android:layout_height="45dp"
            android:layout_gravity="center_horizontal"
            android:background="#FFFFFF"
            android:drawableLeft="@drawable/password"
            android:drawablePadding="6sp"
            android:hint="请再次输入您的密码"
            android:inputType="textPassword"
            android:textColorHint="#A3B1CA"
            android:textSize="15sp" >
        </EditText>
        <View
            android:layout_width="match_parent"
            android:layout_height="0.2dp"
            android:layout_marginTop="2dp"
            android:background="#F2F2F2" >
        </View>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="16dp"
            android:layout_gravity="center_horizontal"
            android:text=" 请输入常用邮箱，便于找回密码"
            android:textColor="#108AC6"
            android:textSize="13sp" >
        </TextView>
        <View
            android:layout_width="match_parent"
            android:layout_height="0.2dp"
            android:layout_marginTop="2dp"
            android:background="#F2F2F2" >
        </View>
        <EditText
            android:id="@+id/RegMail"
            android:layout_width="250dp"
            android:layout_height="45dp"
            android:layout_gravity="center_horizontal"
            android:background="#FFFFFF"
            android:drawableLeft="@drawable/mail"
            android:drawablePadding="6sp"
            android:hint="请输入您的邮箱账号"
            android:inputType="textWebEmailAddress"
            android:textColorHint="#A3B1CA"
            android:textSize="15sp" >
        </EditText>
    </LinearLayout>
    <Button
        android:id="@+id/btnRegister"
        android:layout_width="260dp"
        android:layout_height="48dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="20dp"
        android:background="@drawable/normalbtnstyle"
        android:gravity="center"
        android:text="注  册"
        android:textColor="#FFFFFF"
        android:textSize="20sp"
        android:textStyle="bold" >
    </Button>
</LinearLayout>

注册界面的UI很简单了，还是基础控件的使用，当然UI上面的实现方式很多，初学时根据自己的需要和熟悉程度选择就好……