android 登录界面功能实现

源码：http://download.csdn.net/detail/lm_zp/9526062

功能介绍：

刚进入登录不能点击

只有两个输入框都输入值方可点击

点击小差号删除输入框内容

点击眼睛显示密码

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:background="#0f0"    android:orientation="vertical" >    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_marginLeft="20dp"        android:layout_marginRight="20dp"        android:layout_marginTop="100dp"        android:background="#fff" >        <EditText            android:id="@+id/edit1"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:layout_marginRight="10dp"            android:layout_marginTop="5dp"            android:layout_weight="1"            android:background="@null"            android:hint="请输入用户名"            android:singleLine="true" />        <ImageView            android:id="@+id/image1"            android:layout_width="wrap_content"            android:layout_height="match_parent"            android:layout_gravity="center"            android:layout_marginRight="10dp"            android:background="@drawable/bns_search_del"            android:visibility="invisible" />    </LinearLayout>    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_marginLeft="20dp"        android:layout_marginRight="20dp"        android:layout_marginTop="10dp"        android:background="#fff" >        <EditText            android:id="@+id/edit2"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:layout_marginTop="5dp"            android:layout_weight="10"            android:background="@null"            android:hint="请输入密码"            android:singleLine="true" />        <ImageView            android:id="@+id/image2"            android:layout_width="wrap_content"            android:layout_height="match_parent"            android:layout_gravity="center"            android:layout_marginLeft="10dp"            android:layout_marginRight="10dp"            android:layout_weight="1"            android:background="@drawable/bns_search_del"            android:visibility="invisible" />        <CheckBox            android:id="@+id/checkbox"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_gravity="center"            android:layout_marginRight="10dp"            android:layout_weight="1"            android:background="@drawable/mycheckbox"            android:button="@null" />    </LinearLayout>    <Button        android:id="@+id/button"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_marginTop="10dp"        android:text="登录" /></LinearLayout>

res/drawable文件夹下

mycheckbox.xml

<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="http://schemas.android.com/apk/res/android" >    <item android:state_checked="true"  android:drawable="@drawable/icon_password2"></item>   <item android:state_checked="false"  android:drawable="@drawable/icon_password1"></item>   <item android:drawable="@drawable/icon_password1"></item></selector>

MainActivity.java

package com.example.mylogin;import android.os.Bundle;import android.app.Activity;import android.text.Editable;import android.text.Selection;import android.text.Spannable;import android.text.TextWatcher;import android.text.method.HideReturnsTransformationMethod;import android.text.method.PasswordTransformationMethod;import android.view.Menu;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.CheckBox;import android.widget.CompoundButton;import android.widget.EditText;import android.widget.ImageView;import android.widget.CompoundButton.OnCheckedChangeListener;public class MainActivity extends Activity {private EditText edit1;private EditText edit2;private Button button;private ImageView image1;private ImageView image2;private CheckBox checkBox;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);edit1 = (EditText) findViewById(R.id.edit1);edit2 = (EditText) findViewById(R.id.edit2);button = (Button) findViewById(R.id.button);image1 = (ImageView) findViewById(R.id.image1);image2 = (ImageView) findViewById(R.id.image2);checkBox = (CheckBox) findViewById(R.id.checkbox);button.setEnabled(false);edit1.addTextChangedListener(new TextWatcher() {@Overridepublic void onTextChanged(CharSequence s, int start, int before,int count) {// TODO Auto-generated method stub}@Overridepublic void beforeTextChanged(CharSequence s, int start, int count,int after) {// TODO Auto-generated method stub}@Overridepublic void afterTextChanged(Editable s) {// TODO Auto-generated method stub// 都不为空button显示if (edit1.getText().toString().equals("")|| edit2.getText().toString().equals("")) {button.setEnabled(false);} else {button.setEnabled(true);}// 当有值时小叉号显示if (edit1.getText().toString().equals("")) {image1.setVisibility(View.INVISIBLE);} else {image1.setVisibility(View.VISIBLE);}}});edit2.addTextChangedListener(new TextWatcher() {@Overridepublic void onTextChanged(CharSequence s, int start, int before,int count) {}@Overridepublic void beforeTextChanged(CharSequence s, int start, int count,int after) {}@Overridepublic void afterTextChanged(Editable s) {// TODO Auto-generated method stub// 都不为空button显示if (edit1.getText().toString().equals("")|| edit2.getText().toString().equals("")) {button.setEnabled(false);} else {button.setEnabled(true);}// 当有值时小叉号显示if (edit2.getText().toString().equals("")) {image2.setVisibility(View.INVISIBLE);} else {image2.setVisibility(View.VISIBLE);}}});// 清空用户名image1.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stubedit1.setText("");}});// 清空密码image2.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stubedit2.setText("");}});// 设置第一次输入密码未不可见状态edit2.setTransformationMethod(PasswordTransformationMethod.getInstance());checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {@Overridepublic void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {// TODO Auto-generated method stubif (isChecked) {// 设置EditText文本为可见的edit2.setTransformationMethod(HideReturnsTransformationMethod.getInstance());} else {edit2.setTransformationMethod(PasswordTransformationMethod.getInstance());}// 切换后将EditText光标置于末尾CharSequence charSequence = edit2.getText();if (charSequence instanceof Spannable) {Spannable spanText = (Spannable) charSequence;Selection.setSelection(spanText, charSequence.length());}}});}}