add: syntax and api document

app/src/main/java/com/stardust/view/MarkdownView.java

@@ -0,0 +1,61 @@
+package com.stardust.view;
+
+import android.content.Context;
+import android.os.Build;
+import android.support.annotation.RequiresApi;
+import android.text.Html;
+import android.text.Spanned;
+import android.text.method.ScrollingMovementMethod;
+import android.util.AttributeSet;
+import android.widget.TextView;
+
+import com.zzhoujay.markdown.MarkDown;
+
+/**
+ * Created by Stardust on 2017/2/1.
+ */
+
+public class MarkdownView extends TextView {
+    public MarkdownView(Context context) {
+        super(context);
+        init();
+    }
+
+    public MarkdownView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        init();
+    }
+
+    public MarkdownView(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+        init();
+    }
+
+    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
+    public MarkdownView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
+        super(context, attrs, defStyleAttr, defStyleRes);
+        init();
+    }
+
+    private void init() {
+        setMovementMethod(ScrollingMovementMethod.getInstance());
+        setVerticalScrollBarEnabled(true);
+        setTextIsSelectable(true);
+        setClickable(true);
+    }
+
+    public void loadMarkdown(final String text, final Html.ImageGetter imageGetter) {
+        post(new Runnable() {
+            @Override
+            public void run() {
+                Spanned spanned = MarkDown.fromMarkdown(text, imageGetter, MarkdownView.this);
+                setText(spanned);
+            }
+        });
+    }
+
+    public void loadMarkdown(final String text) {
+        loadMarkdown(text, null);
+    }
+
+}