RemoveView.java

package com.premnirmal.Magnet;

import android.content.Context;
import android.graphics.PixelFormat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.WindowManager;
import android.view.animation.Animation;
import android.widget.ImageView;

/**
 * Created by prem on 7/20/14.
 * ViewHolder for the remove Icon.
 */
class RemoveView {

  View mLayout;
  View mButton;
  View mShadow;
  ImageView mButtonImage;
  private WindowManager mWindowManager;
  private SimpleAnimator mShowAnim;
  private SimpleAnimator mHideAnim;

  private SimpleAnimator mShadowFadeOut;
  private SimpleAnimator mShadowFadeIn;

  private final int buttonBottomPadding;

  boolean shouldBeResponsive = true;

  RemoveView(Context context) {
    mLayout = LayoutInflater.from(context).inflate(R.layout.x_button_holder, null);
    mButton = mLayout.findViewById(R.id.xButton);
    mButtonImage = (ImageView) mLayout.findViewById(R.id.xButtonImg);
    mButtonImage.setImageResource(R.drawable.trash);
    buttonBottomPadding = mButton.getPaddingBottom();
    mShadow = mLayout.findViewById(R.id.shadow);
    mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
    addToWindow(mLayout);
    mShowAnim = new SimpleAnimator(mButton, R.anim.slide_up);
    mHideAnim = new SimpleAnimator(mButton, R.anim.slide_down);
    mShadowFadeIn = new SimpleAnimator(mShadow, android.R.anim.fade_in);
    mShadowFadeOut = new SimpleAnimator(mShadow, android.R.anim.fade_out);
    hide();
  }

  void setIconResId(int id) {
    mButtonImage.setImageResource(id);
  }

  void setShadowBG(int shadowBG) {
    mShadow.setBackgroundResource(shadowBG);
  }

  void show() {
    if (mLayout != null && mLayout.getParent() == null) {
      addToWindow(mLayout);
    }
    mShadowFadeIn.startAnimation();
    mShowAnim.startAnimation();
  }

  void hide() {
    mShadowFadeOut.startAnimation();
    mHideAnim.startAnimation(new Animation.AnimationListener() {
      @Override public void onAnimationStart(Animation animation) {

      }

      @Override public void onAnimationEnd(Animation animation) {
        if (mLayout != null && mLayout.getParent() != null) {
          mWindowManager.removeView(mLayout);
        }
      }

      @Override public void onAnimationRepeat(Animation animation) {

      }
    });
  }

  void onMove(final float x, final float y) {
    if (shouldBeResponsive) {
      final int xTransformed = (int) Math.abs(
          x * 100 / (mButton.getContext().getResources().getDisplayMetrics().widthPixels / 2));
      final int bottomPadding = buttonBottomPadding - (xTransformed / 5);
      if (x < 0) {
        mButton.setPadding(0, 0, xTransformed, bottomPadding);
      } else {
        mButton.setPadding(xTransformed, 0, 0, bottomPadding);
      }
    }
  }

  void destroy() {
    if (mLayout != null && mLayout.getParent() != null) {
      mWindowManager.removeView(mLayout);
    }
    mLayout = null;
    mWindowManager = null;
  }

  private void addToWindow(View layout) {
    WindowManager.LayoutParams params =
        new WindowManager.LayoutParams(WindowManager.LayoutParams.MATCH_PARENT,
            WindowManager.LayoutParams.MATCH_PARENT, WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY,
            WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
                | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN, PixelFormat.TRANSLUCENT);
    mWindowManager.addView(layout, params);
  }
}