增加setOnSlideListener方法，获取当前所选项index

README.md

@@ -73,7 +73,9 @@ CSDN:[http://blog.csdn.net/iamdingruihaha/article/details/71422269](http://blog.
     hsMain.setAnRightOffset();//向右移动一个单元
 
     hsMain.getSelectedString();//获得被选中的文本
-
+
+    hsMain.setOnSlideListener();//当左右滑动时，获取当前所选项的指针
+
 
 ```
 

app/src/main/java/com/example/horizontalscrollselectedview/MainActivity.java

@@ -11,14 +11,15 @@
 import java.util.ArrayList;
 import java.util.List;
 
-public class MainActivity extends AppCompatActivity implements View.OnClickListener {
+public class MainActivity extends AppCompatActivity implements View.OnClickListener, HorizontalselectedView.OnHorizontalViewSlideListener {
 
     private View leftImageView;
     private View rightImageView;
     private HorizontalselectedView hsMain;
     private Button btMain;
     List<String> strings = new ArrayList<String>();
     private TextView tvMain;
+    private TextView tvMainCurrent;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -42,11 +43,12 @@ private void initView() {
         rightImageView = findViewById(R.id.iv_right);
         btMain = ((Button) findViewById(R.id.bt_main));
         tvMain = ((TextView) findViewById(R.id.tv_main));
-
+        tvMainCurrent = ((TextView) findViewById(R.id.tv_main_current));
 
         leftImageView.setOnClickListener(this);
         rightImageView.setOnClickListener(this);
         btMain.setOnClickListener(this);
+        hsMain.setOnSlideListener(this);
     }
 
 
@@ -68,4 +70,9 @@ public void onClick(View view) {
                 break;
         }
     }
+
+    @Override
+    public void currentIndex(int index) {
+        tvMainCurrent.setText("所选项指针：" + index);
+    }
 }

app/src/main/res/layout/activity_main.xml

@@ -84,4 +84,15 @@
         android:layout_marginTop="20dp"
         android:background="@color/gray" />
 
+    <TextView
+        android:padding="5dp"
+        android:gravity="center"
+        android:id="@+id/tv_main_current"
+        android:layout_gravity="center_horizontal"
+        android:layout_width="wrap_content"
+        android:layout_height="50dp"
+        android:textSize="20sp"
+        android:layout_marginTop="20dp"
+        android:background="@color/gray" />
+
 </LinearLayout>

horizontalselectedviewlibrary/src/main/java/com/example/horizontalselectedviewlibrary/HorizontalselectedView.java

@@ -50,6 +50,7 @@ public class HorizontalselectedView extends View {
     private int textWidth = 0;
     private int textHeight = 0;
     private int centerTextHeight = 0;
+    private OnHorizontalViewSlideListener horizontalView;
 
 
     public HorizontalselectedView(Context context) {
@@ -120,6 +121,10 @@ public boolean onTouchEvent(MotionEvent event) {
                             anOffset = 0;
                             n = n - 1;
                             downX = scrollX;
+                            // 回调
+                            if (null != horizontalView) {
+                                horizontalView.currentIndex(n);
+                            }
                         }
                     }
                 } else {
@@ -131,6 +136,10 @@ public boolean onTouchEvent(MotionEvent event) {
                             anOffset = 0;
                             n = n + 1;
                             downX = scrollX;
+                            // 回调
+                            if (null != horizontalView) {
+                                horizontalView.currentIndex(n);
+                            }
                         }
                     }
                 }
@@ -162,6 +171,10 @@ protected void onDraw(Canvas canvas) {
         if (n >= 0 && n <= strings.size() - 1) {//加个保护；防止越界
 
             String s = strings.get(n);//得到被选中的文字
+            // 回调
+            if (null != horizontalView) {
+                horizontalView.currentIndex(n);
+            }
             /**
              * 得到被选中文字 绘制时所需要的宽高
              */
@@ -251,4 +264,19 @@ public String getSelectedString() {
         }
         return null;
     }
+
+    /**
+     * 设置回调函数
+     * @param horizontalView
+     */
+    public void setOnSlideListener(OnHorizontalViewSlideListener horizontalView) {
+        this.horizontalView = horizontalView;
+    }
+
+    /**
+     * 回调函数
+     */
+    public interface OnHorizontalViewSlideListener {
+        void currentIndex(int index);
+    }
 }