diff --git a/README.md b/README.md
index 8f2971a..ec9c615 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ repositories {
 - add to your module gradle file
 
 ```gradle
-implementation 'com.github.dtboy1995:android-sex-ring:0.2.2'
+implementation 'com.github.dtboy1995:android-sex-ring:0.2.3'
 ```
 
 # screenshot
@@ -54,20 +54,22 @@ implementation 'com.github.dtboy1995:android-sex-ring:0.2.2'
 RingView rv = (RingView)findViewById(R.id.ring_view);
 // set progress - true is animated
 rv.go(20, true);
+// set prgress range mapped
+rv.go(10, -20, 30, true);
 // set progress callback
 rv.setCallback(new AVCallback() {
+    // progress 0~100
     @Override
     public void step(int progress) {
-      // progress 0~100
-      tv.setText(String.valueOf(progress));
+
     }
 });
 // set range mapped progress callback [0, 100] map to => [-20, 30]
 rv.setCallback(new AVRangeMapCallback(-20, 30) {
+    // progress -20~30
     @Override
     public void step(int progress) {
-      // progress -20~30
-      tv.setText(String.valueOf(progress));
+
     }
 });
 ```
diff --git a/example/src/main/java/org/ithot/android/example/ring/ExampleActivity.java b/example/src/main/java/org/ithot/android/example/ring/ExampleActivity.java
index 1c244e8..93e0d94 100644
--- a/example/src/main/java/org/ithot/android/example/ring/ExampleActivity.java
+++ b/example/src/main/java/org/ithot/android/example/ring/ExampleActivity.java
@@ -29,6 +29,10 @@ public void go2(View v) {
         ring2.go(30, true);
     }
 
+    public void goRangeMapped(View v) {
+        ring1.go(-20, -20, 30, true);
+    }
+
     public void step1(int progress) {
         tv1.setText(String.valueOf(progress));
     }
diff --git a/example/src/main/res/layout/activity_main.xml b/example/src/main/res/layout/activity_main.xml
index 1db19fb..53e9e0b 100644
--- a/example/src/main/res/layout/activity_main.xml
+++ b/example/src/main/res/layout/activity_main.xml
@@ -53,12 +53,22 @@
     <Button
         android:onClick="go1"
         android:layout_width="200dp"
-        android:layout_height="50dp"
+        android:layout_height="40dp"
         android:layout_gravity="center_horizontal"
         android:layout_marginTop="5dp"
         android:text="GO"
         android:textColor="#646464"
-        android:textSize="20sp" />
+        android:textSize="17sp" />
+
+    <Button
+        android:onClick="goRangeMapped"
+        android:layout_width="200dp"
+        android:layout_height="40dp"
+        android:layout_gravity="center_horizontal"
+        android:layout_marginTop="5dp"
+        android:text="GO Range Mapped"
+        android:textColor="#646464"
+        android:textSize="17sp" />
 
     <RelativeLayout
         android:layout_width="150dp"
@@ -108,10 +118,10 @@
     <Button
         android:onClick="go2"
         android:layout_width="200dp"
-        android:layout_height="50dp"
+        android:layout_height="40dp"
         android:layout_gravity="center_horizontal"
         android:layout_marginTop="5dp"
         android:text="GO"
         android:textColor="#646464"
-        android:textSize="20sp" />
+        android:textSize="17sp" />
 </LinearLayout>
diff --git a/ring/build.gradle b/ring/build.gradle
index 1b6d372..ed265e3 100644
--- a/ring/build.gradle
+++ b/ring/build.gradle
@@ -8,8 +8,8 @@ android {
     defaultConfig {
         minSdkVersion 14
         targetSdkVersion 26
-        versionCode 3
-        versionName "0.2.2"
+        versionCode 4
+        versionName "0.2.3"
     }
 
     buildTypes {
diff --git a/ring/src/main/java/org/ithot/android/view/RingView.java b/ring/src/main/java/org/ithot/android/view/RingView.java
index 147a1d9..00dd3a8 100644
--- a/ring/src/main/java/org/ithot/android/view/RingView.java
+++ b/ring/src/main/java/org/ithot/android/view/RingView.java
@@ -328,6 +328,16 @@ public void go(int progress) {
         go(progress, false);
     }
 
+    public void go(int progress, int min, int max) {
+        float unit = (max - min) / MAX_PROGRESS;
+        go((int) ((progress - min) / unit));
+    }
+
+    public void go(int progress, int min, int max, boolean animate) {
+        float unit = (max - min) / MAX_PROGRESS;
+        go((int) ((progress - min) / unit), true);
+    }
+
     @Override
     protected void onDraw(Canvas canvas) {
         super.onDraw(canvas);