android开发分享详解Android Studio实现用户登陆界面demo（xml实现）

  <linearlayout    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    android:paddingleft="55px"    android:paddingright="50px"    tools:context=".mainactivity">    <textview      android:id="@+id/message"      android:layout_width="wrap_content"      android:layout_height="wrap_content"      android:layout_marginstart="@dimen/activity_horizontal_margin"      android:layout_marginleft="@dimen/activity_horizontal_margin"      android:layout_margintop="@dimen/activity_vertical_margin"      android:text="hello word！"      app:layout_constraintleft_toleftof="parent"      app:layout_constrainttop_totopof="parent" />    <view      android:layout_width="match_parent"      android:layout_height="2px"      android:layout_margintop="16px"      android:background="#000000" />    <textview      android:layout_width="wrap_content"      android:layout_height="wrap_content"      android:textsize="28dp"      android:layout_gravity="center_horizontal"      android:layout_margintop="20px"      android:text="登陆界面" />  <linearlayout    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:orientation="horizontal"    >    <edittext      android:id="@+id/et1"      android:layout_width="280dp"      android:layout_height="wrap_content"      android:layout_margintop="30dp"      android:paddingleft="10dp"      android:hint="请输入账号"      android:inputtype="text"/>    <imageview      android:id="@+id/bt1"      android:layout_width="25dp"      android:layout_height="25dp"      android:layout_margintop="37dp"      android:src="@drawable/delete" />  </linearlayout>    <linearlayout      android:layout_width="match_parent"      android:layout_height="wrap_content"      android:orientation="horizontal"      android:paddingleft="8px">    <edittext      android:id="@+id/et2"      android:layout_width="280dp"      android:layout_height="wrap_content"      android:layout_margintop="26dp"      android:hint="请输入密码"      android:inputtype="textpassword" />      <imageview        android:id="@+id/bt2"        android:layout_width="25dp"        android:layout_height="25dp"        android:layout_margintop="33dp"        android:src="@drawable/delete" />  </linearlayout>      <button        android:id="@+id/btn_login"        android:layout_width="match_parent"        android:layout_height="48dp"        android:background="@color/bbutton_danger_disabled_edge"        android:layout_margintop="30dp"        android:text="登 陆"        android:textsize="30dp"        android:textcolor="@color/bbutton_danger"/>    <button    android:id="@+id/bbt1"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:textsize="15dp"    android:layout_gravity="right"    android:layout_margintop="20px"    android:background="@color/bbutton_danger"    android:text="adapter" />    </linearlayout> 

  /**   * 用于实现点击叉叉时 , 清空输入框的内容   */     class edittextutils {      public static void clearbuttonlistener(final edittext et, final view view) {        // 取得et中的文字        string etinputstring = et.gettext().tostring();        // 根据et中是否有文字进行x可见或不可见的判断        if (textutils.isempty(etinputstring)) {          view.setvisibility(view.invisible);      } else {          view.setvisibility(view.visible);      }        //点击x时使et中的内容为空        view.setonclicklistener(new view.onclicklistener() {          @override        public void onclick(view view) {          et.settext("");          et.requestfocusfromtouch();        }      });      //对et的输入状态进行监听      et.addtextchangedlistener(new textwatcher() {        @override        public void ontextchanged(charsequence s, int start, int before, int count) {        }        @override        public void beforetextchanged(charsequence s, int start, int count, int after) {        }        @override        public void aftertextchanged(editable s) {            if (s.length() == 0) {            view.setvisibility(view.invisible);          } else {            view.setvisibility(view.visible);          }        }      });    }  }

  private textview mtextmessage;  @override  protected void oncreate(bundle savedinstancestate) {    super.oncreate(savedinstancestate);    setcontentview(r.layout.activity_main);    edittext et1 = (edittext) findviewbyid(r.id.et1);    edittext et2 = (edittext) findviewbyid(r.id.et2);    view bt = findviewbyid(r.id.bt1);    view iv = findviewbyid(r.id.bt2);    edittextutils.clearbuttonlistener(et1, bt);    edittextutils.clearbuttonlistener(et2, iv);      button btn1 = (button) findviewbyid(r.id.bbt1);    btn1.setonclicklistener(new view.onclicklistener(){      @override      public void onclick(view v){        //intent是一种运行时绑定（run-time binding）机制，它能在程序运行过程中连接两个不同的组件，在存放资源代码的文件夹下下，        intent i = new intent(mainactivity.this , main2activityadapterdemo.class);        //启动        startactivity(i);        }    });      mtextmessage = (textview) findviewbyid(r.id.message);    bottomnavigationview navigation = (bottomnavigationview) findviewbyid(r.id.navigation);    navigation.setonnavigationitemselectedlistener(monnavigationitemselectedlistener);  }

  <resources>    <!-- default screen margins, per the android design guidelines. -->    <dimen name="activity_horizontal_margin">16dp</dimen>    <dimen name="activity_vertical_margin">16dp</dimen>    <dimen name="text_size_16">22dp</dimen>    <dimen name="space_8">8</dimen>    <dimen name="space_16">16</dimen>    <dimen name="fab_margin">16dp</dimen>  </resources>

  <?xml version="1.0" encoding="utf-8"?>  <resources>    <color name="colorprimary">#008577</color>    <color name="colorprimarydark">#00574b</color>    <color name="coloraccent">#d81b60</color>    <color name="main_gray">#cccccc</color>    <color name="main_black">#000000</color>    <color name="bbutton_danger_disabled_edge">#00cc33</color>    <color name="bbutton_danger">#ffffff</color>  </resources>