Android自定义顶部导航栏控件

class HeaderBar @JvmOverloads constructor(

context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0

) : FrameLayout(context, attrs, defStyleAttr) {

//重写构造方法  在java里面 我们一般是重写三个构造方法//在kotlin中 我们可以使用@JvmOverloads constructor(

//          context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0

//    )后面的两个参数  我们不传的可以使用的是默认值//定义一些变量private var isShowback = true

private var titleText: String? = null

private var rightText: String? = null

//初始化 在init方法中 初始化布局  设置style

init {

//自定义属性val typedArray = context.obtainStyledAttributes(attrs, R.styleable.HeaderBar)

//取出在布局中定义的属性isShowback = typedArray.getBoolean(R.styleable.HeaderBar_isShowBack, true)

titleText = typedArray.getString(R.styleable.HeaderBar_titleText)

rightText = typedArray.getString(R.styleable.HeaderBar_rightText)

initView()

typedArray.recycle()

}

//初始化控件的方法private fun initView() {

//填充布局View.inflate(context, R.layout.layout_header_bar, this)

mLeftIv.visibility = if (isShowback) View.VISIBLE else View.INVISIBLE

titleText?.let {

mTitleTv.text = it

}

rightText?.let {

mRightTv.text = it

mRightTv.visibility = View.VISIBLE

}

mLeftIv.onClick {

if (context is Activity)

(context as Activity).finish()

}

}

fun getRightView(): TextView {

return mRightTv

}

}