Android TouchListener实现拖拽删实例代码

importandroid.util.Log;

importandroid.view.MotionEvent;

importandroid.view.View;

importandroid.view.ViewGroup;

/**

 * Created by zhangjg on 14-10-10.

 */

publicclassDragTouchListenerimplementsView.OnTouchListener {

  /**

   * drag directions

   */

  publicstaticfinalintDIRECTION_UP =0;

  publicstaticfinalintDIRECTION_DOWN =1;

  publicstaticfinalintDIRECTION_LEFT =2;

  publicstaticfinalintDIRECTION_RIGHT =3;

  privateintmDragDirection = -1;

  privateintmDragDistance = -1;

  privateViewGroup.MarginLayoutParams mParams;

  privateViewGroup.MarginLayoutParams mOriginParams;

  privateintviewOriginMargin = -1000;

  privatefloatmStartY =0;

  privatefloatmStartX =0;

  privatebooleanisTouched =false;

  publicDragTouchListener(intdragDirection,intdragDistance){

    mDragDirection = dragDirection;

    mDragDistance = dragDistance;

  }

  protectedvoidonClick(View view){

  }

  protectedvoidonDragComplete(View view){

  }

  protectedvoidonDragRebound(View view){

  }

  @Override

  publicbooleanonTouch(View view, MotionEvent motionEvent) {

    if(viewOriginMargin == -1000){

      mParams = (ViewGroup.MarginLayoutParams)view.getLayoutParams();

      if(mDragDirection == DIRECTION_UP) {

        viewOriginMargin = mParams.bottomMargin;

      }elseif(mDragDirection == DIRECTION_DOWN){

        viewOriginMargin = mParams.topMargin;

      }elseif(mDragDirection == DIRECTION_LEFT){

        viewOriginMargin = mParams.rightMargin;

      }elseif(mDragDirection == DIRECTION_RIGHT){

        viewOriginMargin = mParams.leftMargin;

      }

    }

    intaction = motionEvent.getAction();

    switch(action){

      caseMotionEvent.ACTION_DOWN:

        isTouched =true;

        mStartY = motionEvent.getY();

        mStartX = motionEvent.getX();

        returntrue;

      caseMotionEvent.ACTION_MOVE:

        floaty = motionEvent.getY();

        floatx = motionEvent.getX();

        if(mDragDirection == DIRECTION_UP){

          if(y < mStartY){

            mParams.bottomMargin = viewOriginMargin +(int) (mStartY - y);

          }

        }elseif(mDragDirection == DIRECTION_DOWN){

          if(y > mStartY){

            mParams.topMargin = viewOriginMargin + (int) (y - mStartY);

          }

        }elseif(mDragDirection == DIRECTION_LEFT){

          if(x < mStartX){

            mParams.rightMargin = viewOriginMargin + (int) (mStartX - x);

          }

        }elseif(mDragDirection == DIRECTION_RIGHT){

          if(x > mStartX){

            mParams.leftMargin = viewOriginMargin + (int) (x - mStartX);

          }

        }

        view.setLayoutParams(mParams);

        break;

      caseMotionEvent.ACTION_UP:

        floatnowY = motionEvent.getY();

        floatnowX = motionEvent.getX();

        intdeltaX = (int)nowX - (int)mStartX;

        intdeltaY = (int)nowY - (int)mStartY;

        if(isTouched && Math.abs(deltaX)<5&& Math.abs(deltaY) <5){

          onClick(view);

          break;

        }

        if(mDragDirection == DIRECTION_UP){

          if(isTouched && mStartY - nowY > mDragDistance){

//            Log.i("test-drag", "direction up , startY = " + mStartY + ", nowY = " + nowY +

//                ", startY - nowY = " + (mStartY - nowY) + ", dragDistance : " + mDragDistance);

            onDragComplete(view);

          }elseif(mStartY - nowY >0&& mStartY - nowY < mDragDistance ){

            mParams.bottomMargin = viewOriginMargin;

            view.setLayoutParams(mParams);

            onDragRebound(view);

          }

        }elseif(mDragDirection == DIRECTION_DOWN){

          if(isTouched && nowY - mStartY > mDragDistance){

            onDragComplete(view);

          }elseif( nowY - mStartY >0&& nowY - mStartY < mDragDistance ){

            mParams.topMargin = viewOriginMargin;

            view.setLayoutParams(mParams);

            onDragRebound(view);

          }

        }elseif(mDragDirection == DIRECTION_LEFT){

          if(isTouched && mStartX - nowX > mDragDistance){

            onDragComplete(view);

          }elseif( mStartX - nowX >0&& mStartX - nowX < mDragDistance ){

            mParams.rightMargin = viewOriginMargin;

            view.setLayoutParams(mParams);

            onDragRebound(view);

          }

        }elseif(mDragDirection == DIRECTION_RIGHT){

          if(isTouched && nowX - mStartX > mDragDistance){

            onDragComplete(view);

          }elseif( nowX - mStartX >0&& nowX - mStartX < mDragDistance ){

            mParams.leftMargin = viewOriginMargin;

            view.setLayoutParams(mParams);

            onDragRebound(view);

          }

        }

        isTouched =false;

        break;

    }

    returnfalse;

  }

}