怎么在Android中使用Kotlin实现一个登录界面？很多新手对此不是很清楚，为了帮助大家解决这个难题，下面小编将为大家详细讲解，有这方面需求的人可以来学习下，希望你能有所收获。
登录界面代码如下：
class LoginActivity : AppCompatActivity(), View.OnClickListener {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
//setContentView(R.layout.activity_login)
LoginUi().setContentView(this@LoginActivity)
}
lateinit var et_account: EditText
lateinit var et_password: EditText
inner class LoginUi : AnkoComponent {
override fun createView(ui: AnkoContext) = with(ui) {
verticalLayout {
backgroundColor = context.resources.getColor(android.R.color.white)
gravity = Gravity.CENTER_HORIZONTAL
imageView(R.drawable.touxiang).lparams {
width = dip(100)
height = dip(100)
topMargin = dip(64)
}
linearLayout {
gravity = Gravity.CENTER_VERTICAL
orientation = HORIZONTAL
backgroundResource = R.drawable.bg_frame_corner
imageView {
image = resources.getDrawable(R.mipmap.ic_username)
}.lparams(width = wrapContent, height = wrapContent) {
leftMargin = dip(12)
rightMargin = dip(15)
}
et_account = editText {
hint = "登录账户"
hintTextColor = Color.parseColor("#666666")
textSize = 14f
background = null
}.lparams {
topMargin = dip(5)
}
}.lparams(width = dip(300), height = dip(40)) {
topMargin = dip(30)
}
linearLayout {
gravity = Gravity.CENTER_VERTICAL
orientation = HORIZONTAL
backgroundResource = R.drawable.bg_frame_corner
imageView {
image = resources.getDrawable(R.mipmap.ic_password)
}.lparams(width = wrapContent, height = wrapContent) {
leftMargin = dip(12)
rightMargin = dip(15)
}
et_password = editText {
hint = "账户密码"
hintTextColor = Color.parseColor("#666666")
textSize = 14f
background = null
}.lparams {
topMargin = dip(5)
}
}.lparams {
width = dip(300)
height = dip(40)
topMargin = dip(10)
}
button("登录") {
gravity = Gravity.CENTER
background = resources.getDrawable(R.drawable.bg_login_btn)
textColor = Color.parseColor("#ffffff")
textSize = 18f
onClick {
if (et_account.text.toString().isNotEmpty() && et_password.text.toString().isNotEmpty())
startActivity() else toast("请输入账户或者密码")
}
}.lparams(width = dip(300), height = dip(44)) {
topMargin = dip(18)
}
linearLayout {
orientation = HORIZONTAL
gravity = Gravity.CENTER_VERTICAL
checkBox("记住密码") {
textColor = Color.parseColor("#666666")
textSize = 16f
leftPadding = dip(5)
}
textView("新用户注册") {
textColor = Color.parseColor("#1783e3")
gravity = Gravity.RIGHT
textSize = 16f
}.lparams(width = matchParent)
}.lparams(width = dip(300)) {
topMargin = dip(18)
}
textView("Copyright © Henry") {
textSize = 14f
gravity = Gravity.CENTER or Gravity.BOTTOM
}.lparams {
bottomMargin = dip(35)
weight = 1f
}
}
}
}
override fun onClick(v: View) {
when (v.id) {
}
}
} 实现出来的效果和我们设置布局文件所实现的效果一样，但是相比使用布局文件来说，使用Kotlin将会更加的简洁明了，省去了定义变量和查找布局文件的操作，大大解放了我们程序员；
下面的代码所示是笔者使用布局文件实现的布局效果，和上面的效果一样，但是会复杂很多，大家可以自己自己体会一下；
