Add horizontal padding boolean parameter to customView(...), resolves #1829

core/src/main/java/com/afollestad/materialdialogs/customview/DialogCustomViewExt.kt

@@ -43,12 +43,15 @@ internal const val CUSTOM_VIEW_NO_VERTICAL_PADDING = "md.custom_view_no_vertical
  * @param view The view to insert as the custom view.
  * @param scrollable Whether or not the custom view is automatically wrapped in a ScrollView.
  * @param noVerticalPadding When set to true, vertical padding is not added around your content.
+ * @param horizontalPadding When true, 24dp horizontal padding is applied to your custom view.
+ * @param dialogWrapContent When true, the dialog will wrap the content width.
  */
 fun MaterialDialog.customView(
   @LayoutRes viewRes: Int? = null,
   view: View? = null,
   scrollable: Boolean = false,
   noVerticalPadding: Boolean = false,
+  horizontalPadding: Boolean = false,
   dialogWrapContent: Boolean = false
 ): MaterialDialog {
   assertOneSet("customView", view, viewRes)
@@ -62,7 +65,8 @@ fun MaterialDialog.customView(
   this.view.contentLayout.addCustomView(
       res = viewRes,
       view = view,
-      scrollable = scrollable
+      scrollable = scrollable,
+      horizontalPadding = horizontalPadding
   )
       .also {
         if (dialogWrapContent) {

core/src/main/java/com/afollestad/materialdialogs/internal/message/DialogContentLayout.kt

@@ -62,6 +62,10 @@ class DialogContentLayout(
     get() = parent as DialogLayout
   private var scrollFrame: ViewGroup? = null
   private var messageTextView: TextView? = null
+  private var useHorizontalPadding: Boolean = false
+  private val frameHorizontalMargin: Int by lazy {
+    resources.getDimensionPixelSize(R.dimen.md_dialog_frame_margin_horizontal)
+  }
 
   var scrollView: DialogScrollView? = null
   var recyclerView: DialogRecyclerView? = null
@@ -109,7 +113,8 @@ class DialogContentLayout(
   fun addCustomView(
     @LayoutRes res: Int?,
     view: View?,
-    scrollable: Boolean
+    scrollable: Boolean,
+    horizontalPadding: Boolean
   ): View {
     check(customView == null) { "Custom view already set." }
 
@@ -120,10 +125,21 @@ class DialogContentLayout(
     }
 
     if (scrollable) {
+      // Since the view is going in the main ScrollView, apply padding to custom view.
+      this.useHorizontalPadding = false
       addContentScrollView()
       customView = view ?: inflate(res!!, scrollFrame)
-      scrollFrame!!.addView(customView)
+      scrollFrame!!.addView(customView?.apply {
+        if (horizontalPadding) {
+          updatePadding(
+              left = frameHorizontalMargin,
+              right = frameHorizontalMargin
+          )
+        }
+      })
     } else {
+      // Since the view is NOT going in the main ScrollView, we'll offset it in the layout.
+      this.useHorizontalPadding = horizontalPadding
       customView = view ?: inflate(res!!)
       addView(customView)
     }
@@ -190,7 +206,11 @@ class DialogContentLayout(
         continue
       }
       currentChild.measure(
-          makeMeasureSpec(specWidth, EXACTLY),
+          if (currentChild == customView && useHorizontalPadding) {
+            makeMeasureSpec(specWidth - (frameHorizontalMargin * 2), EXACTLY)
+          } else {
+            makeMeasureSpec(specWidth, EXACTLY)
+          },
           makeMeasureSpec(heightPerRemainingChild, AT_MOST)
       )
       totalChildHeight += currentChild.measuredHeight
@@ -210,11 +230,20 @@ class DialogContentLayout(
     for (i in 0 until childCount) {
       val currentChild = getChildAt(i)
       val currentBottom = currentTop + currentChild.measuredHeight
+      val childLeft: Int
+      val childRight: Int
+      if (currentChild == customView && useHorizontalPadding) {
+        childLeft = frameHorizontalMargin
+        childRight = measuredWidth - frameHorizontalMargin
+      } else {
+        childLeft = 0
+        childRight = measuredWidth
+      }
       currentChild.layout(
-          0,
-          currentTop,
-          measuredWidth,
-          currentBottom
+          /*left=   */childLeft,
+          /*top=    */currentTop,
+          /*right=  */childRight,
+          /*bottom= */currentBottom
       )
       currentTop = currentBottom
     }

sample/src/main/java/com/afollestad/materialdialogssample/MainActivity.kt

@@ -821,7 +821,7 @@ class MainActivity : AppCompatActivity() {
   private fun showCustomViewDialog(dialogBehavior: DialogBehavior = ModalDialog) {
     val dialog = MaterialDialog(this, dialogBehavior).show {
       title(R.string.googleWifi)
-      customView(R.layout.custom_view, scrollable = true)
+      customView(R.layout.custom_view, scrollable = true, horizontalPadding = true)
       positiveButton(R.string.connect) { dialog ->
         // Pull the password out of the custom view when the positive button is pressed
         val passwordInput: EditText = dialog.getCustomView()

sample/src/main/res/layout/custom_view.xml

@@ -5,8 +5,6 @@
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:orientation="vertical"
-    android:paddingLeft="@dimen/md_dialog_frame_margin_horizontal"
-    android:paddingRight="@dimen/md_dialog_frame_margin_horizontal"
     >
 
   <TextView