Add OnProgressChangeListener (close #11)

README.md

@@ -171,6 +171,18 @@ Acceptable values are from 0 to 360 degrees. But be aware that they go clockwise
 
 ---
 
+#### Listening to progress changes
+```java
+circularProgress.setOnProgressChangeListener(new CircularProgressIndicator.OnProgressChangeListener() {
+            @Override
+            public void onProgressChanged(double progress, double maxProgress) {
+                Log.d("PROGRESS", String.format("Current: %1$.0f, max: %2$.0f", progress, maxProgress));
+            }
+        });
+```
+
+---
+
 ### Download using Gradle
 
 Add this in your root `build.gradle` at the end of `repositories` in `allprojects` section:

circularprogressindicator/src/main/java/antonkozyriatskyi/circularprogressindicator/CircularProgressIndicator.java

@@ -84,6 +84,9 @@ public class CircularProgressIndicator extends View {
     @NonNull
     private ProgressTextAdapter progressTextAdapter;
 
+    @Nullable
+    private OnProgressChangeListener onProgressChangeListener;
+
     public CircularProgressIndicator(Context context) {
         super(context);
         init(context, null);
@@ -334,6 +337,10 @@ public void setProgress(double current, double max) {
         maxProgressValue = max;
         progressValue = Math.min(current, max);
 
+        if (onProgressChangeListener != null) {
+            onProgressChangeListener.onProgressChanged(progressValue, maxProgressValue);
+        }
+
         reformatProgressText();
         calculateTextBounds();
 
@@ -574,6 +581,15 @@ public void setProgressStrokeCap(@Cap int cap) {
         }
     }
 
+    public void setOnProgressChangeListener(@Nullable OnProgressChangeListener onProgressChangeListener) {
+        this.onProgressChangeListener = onProgressChangeListener;
+    }
+
+    @Nullable
+    public OnProgressChangeListener getOnProgressChangeListener() {
+        return onProgressChangeListener;
+    }
+
     @IntDef({DIRECTION_CLOCKWISE, DIRECTION_COUNTERCLOCKWISE})
     public @interface Direction {
     }
@@ -587,4 +603,8 @@ public interface ProgressTextAdapter {
         @NonNull
         String formatText(double currentProgress);
     }
+
+    public interface OnProgressChangeListener {
+        void onProgressChanged(double progress, double maxProgress);
+    }
 }

example/src/main/java/antonkozyriatskyi/circularprogressindicatorexample/MainActivity.java

@@ -3,6 +3,7 @@
 import android.graphics.Color;
 import android.os.Bundle;
 import android.support.v7.app.AppCompatActivity;
+import android.util.Log;
 import android.view.View;
 import android.widget.Button;
 import android.widget.CheckBox;
@@ -80,6 +81,13 @@ public void onCheckedChanged(RadioGroup group, int checkedId) {
                 }
             }
         });
+
+        circularProgress.setOnProgressChangeListener(new CircularProgressIndicator.OnProgressChangeListener() {
+            @Override
+            public void onProgressChanged(double progress, double maxProgress) {
+                Log.d("PROGRESS", String.format("Current: %1$.0f, max: %2$.0f", progress, maxProgress));
+            }
+        });
     }
 
     @Override