sample, add TaskListMutateNestedSample

app-sample/samples.json

@@ -1,4 +1,16 @@
 [
+  {
+    "javaClassName": "io.noties.markwon.app.samples.tasklist.TaskListMutateNestedSample",
+    "id": "20211228120444",
+    "title": "Task list mutate nested",
+    "description": "Task list mutation with nested items",
+    "artifacts": [
+      "EXT_TASKLIST"
+    ],
+    "tags": [
+      "plugin"
+    ]
+  },
   {
     "javaClassName": "io.noties.markwon.app.samples.image.ClickImageSample",
     "id": "20201221130230",

app-sample/src/main/java/io/noties/markwon/app/samples/tasklist/TaskListMutateNestedSample.kt

@@ -0,0 +1,157 @@
+package io.noties.markwon.app.samples.tasklist
+
+import android.text.style.ClickableSpan
+import android.view.View
+import io.noties.debug.Debug
+import io.noties.markwon.AbstractMarkwonPlugin
+import io.noties.markwon.Markwon
+import io.noties.markwon.MarkwonVisitor
+import io.noties.markwon.SoftBreakAddsNewLinePlugin
+import io.noties.markwon.SpannableBuilder
+import io.noties.markwon.app.sample.Tags
+import io.noties.markwon.app.sample.ui.MarkwonTextViewSample
+import io.noties.markwon.ext.tasklist.TaskListItem
+import io.noties.markwon.ext.tasklist.TaskListPlugin
+import io.noties.markwon.ext.tasklist.TaskListProps
+import io.noties.markwon.ext.tasklist.TaskListSpan
+import io.noties.markwon.sample.annotations.MarkwonArtifact
+import io.noties.markwon.sample.annotations.MarkwonSampleInfo
+import org.commonmark.node.AbstractVisitor
+import org.commonmark.node.Block
+import org.commonmark.node.HardLineBreak
+import org.commonmark.node.Node
+import org.commonmark.node.Paragraph
+import org.commonmark.node.SoftLineBreak
+import org.commonmark.node.Text
+
+@MarkwonSampleInfo(
+  id = "20211228120444",
+  title = "Task list mutate nested",
+  description = "Task list mutation with nested items",
+  artifacts = [MarkwonArtifact.EXT_TASKLIST],
+  tags = [Tags.plugin]
+)
+class TaskListMutateNestedSample : MarkwonTextViewSample() {
+  override fun render() {
+    val md = """
+      # Task list
+      - [ ] not done
+      - [X] done
+        - [ ] nested not done 
+          and text and textand text and text
+        - [X] nested done
+    """.trimIndent()
+
+    val markwon = Markwon.builder(context)
+      .usePlugin(TaskListPlugin.create(context))
+      .usePlugin(SoftBreakAddsNewLinePlugin.create())
+      .usePlugin(object : AbstractMarkwonPlugin() {
+        override fun configureVisitor(builder: MarkwonVisitor.Builder) {
+          builder.on(TaskListItem::class.java) { visitor, node ->
+
+            val length = visitor.length()
+
+            visitor.visitChildren(node)
+
+            TaskListProps.DONE.set(visitor.renderProps(), node.isDone)
+
+            val spans = visitor.configuration()
+              .spansFactory()
+              .get(TaskListItem::class.java)
+              ?.getSpans(visitor.configuration(), visitor.renderProps())
+
+            if (spans != null) {
+
+              val taskListSpan = if (spans is Array<*>) {
+                spans.first { it is TaskListSpan } as? TaskListSpan
+              } else {
+                spans as? TaskListSpan
+              }
+
+              Debug.i("#### ${visitor.builder().substring(length, length + 3)}")
+              val content = TaskListContextVisitor.contentLength(node)
+              Debug.i("#### content: $content, '${visitor.builder().subSequence(length, length + content)}'")
+
+              if (content > 0 && taskListSpan != null) {
+                // maybe additionally identify this task list (for persistence)
+                visitor.builder().setSpan(
+                  ToggleTaskListSpan(taskListSpan, visitor.builder().substring(length, length + content)),
+                  length,
+                  length + content
+                )
+              }
+            }
+
+            SpannableBuilder.setSpans(
+              visitor.builder(),
+              spans,
+              length,
+              visitor.length()
+            )
+
+            if (visitor.hasNext(node)) {
+              visitor.ensureNewLine()
+            }
+          }
+        }
+      })
+      .build()
+
+    markwon.setMarkdown(textView, md)
+  }
+
+  class TaskListContextVisitor : AbstractVisitor() {
+
+    companion object {
+      fun contentLength(node: Node): Int {
+        val visitor = TaskListContextVisitor()
+        visitor.visitChildren(node)
+        return visitor.contentLength
+      }
+    }
+
+    var contentLength: Int = 0
+
+    override fun visit(text: Text) {
+      super.visit(text)
+      contentLength += text.literal.length
+    }
+
+    // NB! if count both soft and hard breaks as having length of 1
+    override fun visit(softLineBreak: SoftLineBreak?) {
+      super.visit(softLineBreak)
+      contentLength += 1
+    }
+
+    // NB! if count both soft and hard breaks as having length of 1
+    override fun visit(hardLineBreak: HardLineBreak?) {
+      super.visit(hardLineBreak)
+      contentLength += 1
+    }
+
+    override fun visitChildren(parent: Node) {
+      var node = parent.firstChild
+      while (node != null) {
+        // A subclass of this visitor might modify the node, resulting in getNext returning a different node or no
+        // node after visiting it. So get the next node before visiting.
+        val next = node.next
+        if (node is Block && node !is Paragraph) {
+          break
+        }
+        node.accept(this)
+        node = next
+      }
+    }
+  }
+
+  class ToggleTaskListSpan(
+    val span: TaskListSpan,
+    val content: String
+  ) : ClickableSpan() {
+    override fun onClick(widget: View) {
+      span.isDone = !span.isDone
+      widget.invalidate()
+      Debug.i("task-list click, isDone: ${span.isDone}, content: '$content'")
+    }
+  }
+}

app-sample/src/main/java/io/noties/markwon/app/samples/tasklist/TaskListMutateSample.java

@@ -32,6 +32,10 @@ import static io.noties.markwon.app.samples.tasklist.shared.TaskListHolder.MD;
 public class TaskListMutateSample extends MarkwonTextViewSample {
   @Override
   public void render() {
+
+    // NB! this sample works for a single level task list,
+    //  if you have multiple levels, then see the `TaskListMutateNestedSample`
+
     final Markwon markwon = Markwon.builder(context)
       .usePlugin(TaskListPlugin.create(context))
       .usePlugin(new AbstractMarkwonPlugin() {
@@ -63,9 +67,8 @@ public class TaskListMutateSample extends MarkwonTextViewSample {
 
     markwon.setMarkdown(textView, MD);
   }
-}
 
-class TaskListToggleSpan extends ClickableSpan {
+  static class TaskListToggleSpan extends ClickableSpan {
 
     private final TaskListSpan span;
 
@@ -98,4 +101,5 @@ class TaskListToggleSpan extends ClickableSpan {
     public void updateDrawState(@NonNull TextPaint ds) {
       // no op, so text is not rendered as a link
     }
+  }
 }