SwipeBackActivity.java

package com.bob.digcsdn.utils;

import android.app.Activity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.RelativeLayout.LayoutParams;

import com.bob.digcsdn.R;

/**
 * Created by Eric on 15/3/3.
 */
public class SwipeBackActivity extends Activity implements SwipeBackLayout.SwipeBackListener {

    private SwipeBackLayout swipeBackLayout;
    private ImageView ivShadow;

    @Override
    public void setContentView(int layoutResID) {
        super.setContentView(getContainer());
        View view = LayoutInflater.from(this).inflate(layoutResID, null);
        swipeBackLayout.addView(view);
    }

    private View getContainer() {
        RelativeLayout container = new RelativeLayout(this);
        swipeBackLayout = new SwipeBackLayout(this);
        swipeBackLayout.setOnSwipeBackListener(this);
        ivShadow = new ImageView(this);
        ivShadow.setBackgroundColor(getResources().getColor(R.color.black));
        LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
        container.addView(ivShadow, params);
        container.addView(swipeBackLayout);
        return container;
    }

    public void setDragEdge(SwipeBackLayout.DragEdge dragEdge) {
        swipeBackLayout.setDragEdge(dragEdge);
    }

    public SwipeBackLayout getSwipeBackLayout() {
        return swipeBackLayout;
    }

    @Override
    public void onViewPositionChanged(float fractionAnchor, float fractionScreen) {
        ivShadow.setAlpha(1 - fractionScreen);
    }

}