Android 用建造者模式模式写一个Dialog

建造者模式理解

建造者模式（Builder Pattern）使用多个简单的对象一步一步构建成一个复杂的对象。
这种类型的设计 模式属于创建型模式，它提供了一种创建对象的最佳方式。

何时使用：一些基本部件不会变，而其组合经常变化的时候。
如何解决：将变与不变分离开。
优点： 1、建造者独立，易扩展。 2、便于控制细节风险。
缺点： 1、产品必须有共同点，范围有限制。 2、如内部变化复杂，会有很多的建造类。

class CustomDialog(context: Context): Dialog(context,R.style.MyDialogStyle){
    var title: String? = null//对话框标题
    var message : String? = null//对话框内容
    var confirmBtnText : String? = null //按钮名称“确定”
    var cancelBtnText: String? = null //按钮名称“取消”
    var mContentView: View? = null //对话框中间加载的其他布局界面
    var isOutside: Boolean = true //对话框中间加载的其他布局界面
    //按钮监听事件
    var confirmBtnClickListener: DialogInterface.OnClickListener? = null
    var cancelBtnClickListener: DialogInterface.OnClickListener? = null


    abstract class Custom(context: Context) {
        var custom = CustomDialog(context)
            protected set
        abstract fun setTitle(title: String):Custom
        abstract fun setMessage(message: String):Custom
        abstract fun setContentView(contentView: View):Custom
        abstract fun isOutside(boolean: Boolean):Custom
        abstract fun setPositiveButton(confirm: String, listener: DialogInterface.OnClickListener):Custom
        abstract fun setNegativeButton(cancel: String, listener: DialogInterface.OnClickListener):Custom
        open fun build(): CustomDialog {
            val inflater = custom.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater
            val contentView: View = inflater.inflate(R.layout.dialog_custom_1, null)
            val titleView = contentView.findViewById<TextView>(R.id.title)
            val confirmBtn = contentView.findViewById<TextView>(R.id.confirm_btn)
            val cancelBtn = contentView.findViewById<TextView>(R.id.cancel_btn)
            val mTVMsg = contentView.findViewById<TextView>(R.id.message)
            val btnView = contentView.findViewById<View>(R.id.btn_view)
            val llMessage = contentView.findViewById<LinearLayout>(R.id.ll_message)
            val topline = contentView.findViewById<View>(R.id.ll_btn_topline)
            val llBtn = contentView.findViewById<LinearLayout>(R.id.ll_btn)
            custom.apply {

                setContentView(contentView)

                // 设置标题
                title?.let {
                    titleView.text = it
                    titleView.paint.isFakeBoldText = true
                }?:run {
                    titleView.visibility = View.GONE
                }

                // 设置确定按钮
                confirmBtnText?.let {
                    confirmBtn.text = it
                    confirmBtn.setOnClickListener {
                        confirmBtnClickListener?.onClick(this, Dialog.BUTTON_POSITIVE)
                        dismiss()
                    }
                }?:run {
                    confirmBtn.visibility = View.GONE
                    btnView.visibility = View.GONE
                }

                // 设置取消按钮
                cancelBtnText?.let {
                    cancelBtn.text = it
                    cancelBtn.setOnClickListener {
                        cancelBtnClickListener?.onClick(this, Dialog.BUTTON_POSITIVE)
                        dismiss()
                    }
                }?:run {
                    cancelBtn.visibility = View.GONE
                    btnView.visibility = View.GONE
                }

                if(confirmBtnText==null&&cancelBtnText==null){
                    llBtn.visibility = View.GONE
                    topline.visibility = View.GONE
                }else{
                    llBtn.visibility = View.VISIBLE
                    topline.visibility = View.VISIBLE
                }


                // 设置内容
                message?.let {
                    mTVMsg.text = it
                }?:run {
                    mContentView.let {
                        llMessage.removeView(mTVMsg)
                        llMessage.addView(
                            it, LinearLayout.LayoutParams(
                                LinearLayout.LayoutParams.WRAP_CONTENT,
                                LinearLayout.LayoutParams.WRAP_CONTENT
                            )
                        )
                    }
                }

                //设置对话框大小
                val dialogWindow: Window? = window
                val lp = dialogWindow?.attributes
                val d = context.resources.displayMetrics
                lp?.width = (d.widthPixels * 0.8).toInt()
                dialogWindow?.attributes = lp
                setCanceledOnTouchOutside(isOutside)
            }
            return custom
        }
    }

    class Builder(context: Context) : CustomDialog.Custom(context) {
        override fun setTitle(title: String) =  with(this){
            custom.title = title
            this
        }

        override fun setMessage(message: String)  =  with(this){
            custom.message = message
            this
        }

        override fun setContentView(contentView: View)  =  with(this){
            custom.mContentView = contentView
            this
        }

        override fun isOutside(boolean: Boolean)  =  with(this){
            custom.isOutside = boolean
            this
        }

        override fun setPositiveButton(confirm: String, listener: DialogInterface.OnClickListener)  =  with(this){
            custom.confirmBtnText = confirm
            custom.confirmBtnClickListener = listener
            this
        }

        override fun setNegativeButton(cancel: String, listener: DialogInterface.OnClickListener)  =  with(this){
            custom.cancelBtnText = cancel
            custom.cancelBtnClickListener = listener
            this
        }
    }
}

    <style name="MyDialogStyle">
        <item name="android:windowBackground">@android:color/transparent</item>
        <item name="android:windowFrame">@null</item>
        <item name="android:windowNoTitle">true</item>
        <item name="android:windowIsFloating">true</item>
        <item name="android:windowIsTranslucent">true</item>
        <item name="android:windowContentOverlay">@null</item>
        <item name="android:windowAnimationStyle">@android:style/Animation.Dialog</item>
        <item name="android:backgroundDimEnabled">true</item>
    </style>

<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/dialog_layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/login_bg"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    android:layout_marginBottom="10dp">
    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="1dp"
        android:gravity="center_horizontal"
        android:padding="20dp"
        tools:text="@string/gps_tip"
        android:textColor="#282828"
        android:textSize="18sp" />
    <LinearLayout
        android:id="@+id/ll_message"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
        <TextView
            android:id="@+id/message"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            tools:text="确定执行该操作dsfdsfsdfsdfsdfsdfsdfsdfsdfsdfdsf？"
            android:textSize="16sp"
            android:gravity="center_horizontal"
            android:textColor="#383838"
            android:layout_marginBottom="20dp"
            />
    </LinearLayout>
    <View
        android:id="@+id/ll_btn_topline"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="#A8A7A7"
        />
    <LinearLayout
        android:id="@+id/ll_btn"
        android:layout_width="match_parent"
        android:layout_height="50dp">
        <TextView
            android:layout_marginTop="10dp"
            android:layout_marginBottom="10dp"
            android:id="@+id/cancel_btn"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="match_parent"
            android:text="@string/cancel"
            android:textSize="16sp"
            android:focusable="true"
            android:clickable="true"
            android:gravity="center"
            android:textColor="#00B2EE"
            />
        <View
            android:id="@+id/btn_view"
            android:layout_width="1dp"
            android:layout_height="match_parent"
            android:background="#A8A7A7"
            />
        <TextView
            android:layout_marginTop="10dp"
            android:layout_marginBottom="10dp"
            android:id="@+id/confirm_btn"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="match_parent"
            android:text="@string/sure"
            android:textSize="16sp"
            android:focusable="true"
            android:clickable="true"
            android:gravity="center"
            android:textColor="#E91E63"
            />
    </LinearLayout>
</LinearLayout>

CustomDialog customDialog= new CustomDialog.Builder(this)
                        .setTitle("Title")
                        .setMessage("Message")
                        .setNegativeButton("取消", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {

                            }
                        })
                        .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {

                            }
                        })
                        .build();
customDialog.show();