Android仿微信activity滑动关闭效果

BaseActivity:
public class BaseSlideCloseActivity extends AppCompatActivity implements
  SlidingPaneLayout.PanelSlideListener {

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  initSlideBackClose();
  super.onCreate(savedInstanceState);
 }

 private void initSlideBackClose() {
  if (isSupportSwipeBack()) {
   SlidingPaneLayout slidingPaneLayout = new SlidingPaneLayout(this);
   // 通过反射改变mOverhangSize的值为0，
   // 这个mOverhangSize值为菜单到右边屏幕的最短距离，
   // 默认是32dp，现在给它改成0
   try {
    Field overhangSize = SlidingPaneLayout.class.getDeclaredField("mOverhangSize");
    overhangSize.setAccessible(true);
    overhangSize.set(slidingPaneLayout, 0);
   } catch (Exception e) {
    e.printStackTrace();
   }
   slidingPaneLayout.setPanelSlideListener(this);
   slidingPaneLayout.setSliderFadeColor(getResources()
     .getColor(android.R.color.transparent));

   // 左侧的透明视图
   View leftView = new View(this);
   leftView.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
   slidingPaneLayout.addView(leftView, 0);

   ViewGroup decorView = (ViewGroup) getWindow().getDecorView();


   // 右侧的内容视图
   ViewGroup decorChild = (ViewGroup) decorView.getChildAt(0);
   decorChild.setBackgroundColor(getResources()
     .getColor(android.R.color.white));
   decorView.removeView(decorChild);
   decorView.addView(slidingPaneLayout);

   // 为 SlidingPaneLayout 添加内容视图
   slidingPaneLayout.addView(decorChild, 1);
  }
 }

 protected boolean isSupportSwipeBack() {
  return true;
 }

 @Override
 public void onPanelSlide(View panel, float slideOffset) {

 }

 @Override
 public void onPanelOpened(View panel) {
  finish();
 }

 @Override
 public void onPanelClosed(View panel) {

 }
}