Android HorizontalScrollView内子控件横向拖拽实例代码
投稿:lqh
本文主要介绍Android HorizontalScrollView的使用,这里给大家一个实例来展示HorizontalScrollView内子控件横向拖拽的效果实现,有需要的小伙伴可以参考下
前言
网上ListView上下拖动的例子有,效果也很好,但是项目要横着拖的,只要硬着头皮自己写(主要是没找到合适的),参考文章1修改而来,分享一下。
正文
截图
实现代码:
public class HoDragActivity extends Activity { private LinearLayout main; private GestureDetector mGestureDetector; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main_cc); main = (LinearLayout) findViewById(R.id.main); bindDrapListener(R.id.myimage1); bindDrapListener(R.id.myimage2); bindDrapListener(R.id.myimage3); bindDrapListener(R.id.myimage4); bindDrapListener(R.id.myimage5); bindDrapListener(R.id.myimage6); bindDrapListener(R.id.myimage7); bindDrapListener(R.id.myimage8); bindDrapListener(R.id.myimage9); bindDrapListener(R.id.myimage10); bindDrapListener(R.id.myimage11); bindDrapListener(R.id.myimage12); mGestureDetector = new GestureDetector(this, new DrapGestureListener()); } private View mDrapView; private void bindDrapListener(int id) { View v = findViewById(id); v.setOnTouchListener(mOnTouchListener); v.setOnDragListener(mOnDragListener); } private OnTouchListener mOnTouchListener = new OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { mDrapView = v; if (mGestureDetector.onTouchEvent(event)) return true; switch (event.getAction() & MotionEvent.ACTION_MASK) { case MotionEvent.ACTION_UP: break; } return false; } }; private OnDragListener mOnDragListener = new OnDragListener() { @Override public boolean onDrag(View v, DragEvent event) { switch (event.getAction()) { case DragEvent.ACTION_DRAG_STARTED: // Do nothing break; case DragEvent.ACTION_DRAG_ENTERED: v.setAlpha(0.5F); break; case DragEvent.ACTION_DRAG_EXITED: v.setAlpha(1F); break; case DragEvent.ACTION_DROP: View view = (View) event.getLocalState(); for (int i = 0, j = main.getChildCount(); i < j; i++) { if (main.getChildAt(i) == v) { // 当前位置 main.removeView(view); main.addView(view, i); break; } } break; case DragEvent.ACTION_DRAG_ENDED: v.setAlpha(1F); default: break; } return true; } }; private class DrapGestureListener extends SimpleOnGestureListener { @Override public boolean onSingleTapConfirmed(MotionEvent e) { return super.onSingleTapConfirmed(e); } @Override public void onLongPress(MotionEvent e) { super.onLongPress(e); ClipData data = ClipData.newPlainText("", ""); MyDragShadowBuilder shadowBuilder = new MyDragShadowBuilder( mDrapView); mDrapView.startDrag(data, shadowBuilder, mDrapView, 0); } @Override public boolean onDown(MotionEvent e) { return true; } } private class MyDragShadowBuilder extends View.DragShadowBuilder { private final WeakReference<View> mView; public MyDragShadowBuilder(View view) { super(view); mView = new WeakReference<View>(view); } @Override public void onDrawShadow(Canvas canvas) { canvas.scale(1.5F, 1.5F); super.onDrawShadow(canvas); } @Override public void onProvideShadowMetrics(Point shadowSize, Point shadowTouchPoint) { // super.onProvideShadowMetrics(shadowSize, shadowTouchPoint); final View view = mView.get(); if (view != null) { shadowSize.set((int) (view.getWidth() * 1.5F), (int) (view.getHeight() * 1.5F)); shadowTouchPoint.set(shadowSize.x / 2, shadowSize.y / 2); } else { // Log.e(View.VIEW_LOG_TAG, // "Asked for drag thumb metrics but no view"); } } } }
代码说明
1、 MyDragShadowBuilder主要用于缩放拖拽的ImageView,这里放大了1.5倍,而又不至于影响原控件,这里是放大两倍
2、这里是通过长按来唤起拖拽操作,所以监听了onLongPress。
3、注意拖拽onDragListener是Android 3.0才新增的API。
以上就是Android HorizontalScrollView内子控件横向拖拽实例,欢迎交流,有需要参考下。