Fixed placeholder animation (async processiong & nested layouts cases)

Author: kbiakov

codeview/src/main/java/io/github/kbiakov/codeview/CodeView.kt

@@ -122,6 +122,7 @@ class CodeView : RelativeLayout {
     /**
      * Add task to build queue. Otherwise (for prepared view) performs
      * task delayed or immediately (for built view).
+     *
      * A little part of view builder.
      *
      * @param task Task to process
@@ -149,8 +150,8 @@ class CodeView : RelativeLayout {
     // - View builder
 
     /**
-     * Specify color theme: syntax colors (need to highlighting) & related to
-     * code view (numeration color & background, content backgrounds).
+     * Specify color theme: syntax colors (need to highlighting) & related
+     * to code view (numeration color & background, content backgrounds).
      *
      * @param colorTheme Default or custom color theme
      */
@@ -172,7 +173,9 @@ class CodeView : RelativeLayout {
      * @param language Language to highlight
      */
     fun highlightCode(language: String) = addTask {
-        adapter.highlightCode(language)
+        adapter.highlightCode(language) {
+            refreshAnimated()
+        }
     }
 
     /**
@@ -208,7 +211,7 @@ class CodeView : RelativeLayout {
      * @param isVisible Shadows visibility
      */
     fun setShadowsVisible(isVisible: Boolean = true) = addTask {
-        val visibility = if (isVisible) View.VISIBLE else GONE
+        val visibility = if (isVisible) VISIBLE else GONE
         vShadowRight.visibility = visibility
         vShadowBottomLine.visibility = visibility
         vShadowBottomContent.visibility = visibility
@@ -237,7 +240,7 @@ class CodeView : RelativeLayout {
      *
      * When layout have multiple code views it becomes a very expensive task.
      * Some task proceeds asynchronously, some not, but what is key point:
-     * it should starts delayed a little bit to show necessary UI immediately.
+     * it should be started delayed a little bit to show necessary UI immediately.
      *
      * @param content Code content
      */
@@ -293,7 +296,7 @@ class CodeView : RelativeLayout {
 
         vPlaceholder.layoutParams = LayoutParams(
                 LayoutParams.MATCH_PARENT, height)
-        vPlaceholder.visibility = View.VISIBLE
+        vPlaceholder.alpha = 1f
     }
 
     // - Animations
@@ -302,7 +305,7 @@ class CodeView : RelativeLayout {
             .setDuration(350)
             .alpha(0f)
             .didAnimated {
-                vPlaceholder.visibility = View.GONE
+                vPlaceholder.alpha = 0f
             }
 
     private fun refreshAnimated() = animate()

codeview/src/main/java/io/github/kbiakov/codeview/adapters/AbstractCodeAdapter.kt

@@ -128,31 +128,16 @@ abstract class AbstractCodeAdapter<T> : RecyclerView.Adapter<AbstractCodeAdapter
         notifyDataSetChanged()
     }
 
-    /**
-     * Highlight code content.
-     *
-     * @param language Programming language to highlight
-     */
-    fun highlightCode(language: String) {
-        async() {
-            highlighting(language)
-        }
-    }
-
     /**
      * Highlight code content.
      *
      * @param onReady Callback when content is highlighted
+     * @param language Programming language to highlight
      */
-    fun highlightCode(onReady: () -> Unit) {
+    fun highlightCode(language: String? = null, onReady: () -> Unit) {
         async() {
-            val processor = CodeProcessor.getInstance(mContext)
-
-            val language = if (processor.isTrained)
-                processor.classify(mContent).get()
-            else CodeClassifier.DEFAULT_LANGUAGE
-
-            highlighting(language, onReady)
+            val classifiedLanguage = language ?: classifyContent()
+            highlighting(classifiedLanguage, onReady)
         }
     }
 
@@ -168,23 +153,46 @@ abstract class AbstractCodeAdapter<T> : RecyclerView.Adapter<AbstractCodeAdapter
 
     // - Helpers (for accessors)
 
-    private fun updateContent(codeLines: List<String>, onUpdated: () -> Unit) {
-        ui {
-            mLines = codeLines
-            onUpdated()
-        }
-    }
+    /**
+     * Classify current code content.
+     *
+     * @return Classified language
+     */
+    private fun classifyContent(): String {
+        val processor = CodeProcessor.getInstance(mContext)
 
-    private fun refresh() = {
-        notifyDataSetChanged()
+        val language = if (processor.isTrained)
+            processor.classify(mContent).get()
+        else CodeClassifier.DEFAULT_LANGUAGE
+
+        return language
     }
 
-    private fun highlighting(language: String, onReady: () -> Unit = refresh()) {
+    /**
+     * Highlight code content by language.
+     *
+     * @param language Language to highlight
+     * @param onReady Callback
+     */
+    private fun highlighting(language: String, onReady: () -> Unit) {
         val code = CodeHighlighter.highlight(language, mContent, colorTheme)
         val lines = extractLines(code)
         updateContent(lines, onReady)
     }
 
+    /**
+     * Return control to UI-thread when highlighted content is ready.
+     *
+     * @param codeLines Highlighted code lines
+     * @param onUpdated Control callback
+     */
+    private fun updateContent(codeLines: List<String>, onUpdated: () -> Unit) {
+        ui {
+            mLines = codeLines
+            onUpdated()
+        }
+    }
+
     private fun showAllBottomNote() = mContext.getString(R.string.show_all)
 
     private fun monoTypeface() = MonoFontCache.getInstance(mContext).typeface