仿微信滑动返回

核心代码：

import java.io.File;
import java.io.FileOutputStream;
import java.lang.reflect.Field;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Rect;
import android.os.Bundle;
import android.support.v4.widget.SlidingPaneLayout;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.LinearLayout;

/**
* @Title: ${file_name}
* @Description: 带视觉差的滑动返回
*/
public class ParallaxSwipeBackActivity extends  Activity implements SlidingPaneLayout.PanelSlideListener {

private final static String TAG = ParallaxSwipeBackActivity.class.getSimpleName();
private final static String WINDOWBITMAP = "screenshots.jpg";
private File mFileTemp;
private SlidingPaneLayout slidingPaneLayout;
private FrameLayout frameLayout;
private ImageView behindImageView;
private ImageView shadowImageView;
private int defaultTranslationX = 100;
private int shadowWidth = 20;

@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
//通过反射来改变SlidingPanelayout的值
try {
slidingPaneLayout = new SlidingPaneLayout(this);
Field f_overHang = SlidingPaneLayout.class.getDeclaredField("mOverhangSize");
f_overHang.setAccessible(true);
f_overHang.set(slidingPaneLayout, 0);
slidingPaneLayout.setPanelSlideListener(this);
slidingPaneLayout.setSliderFadeColor(getResources().getColor(android.R.color.transparent));
} catch (Exception e) {
e.printStackTrace();
}
super.onCreate(savedInstanceState);
mFileTemp = new File(getCacheDir(), WINDOWBITMAP);
defaultTranslationX = dip2px(defaultTranslationX);
shadowWidth = dip2px(shadowWidth);
//behindframeLayout
FrameLayout behindframeLayout = new FrameLayout(this);
behindImageView = new ImageView(this);
behindImageView.setLayoutParams(new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT, FrameLayout.LayoutParams.MATCH_PARENT));
behindframeLayout.addView(behindImageView, 0);

//containerLayout
LinearLayout containerLayout = new LinearLayout(this);
containerLayout.setOrientation(LinearLayout.HORIZONTAL);
containerLayout.setBackgroundColor(getResources().getColor(android.R.color.transparent));
containerLayout.setLayoutParams(new ViewGroup.LayoutParams(getWindowManager().getDefaultDisplay().getWidth() + shadowWidth, ViewGroup.LayoutParams.MATCH_PARENT));
//you view container
frameLayout = new FrameLayout(this);
frameLayout.setBackgroundColor(getResources().getColor(android.R.color.white));
frameLayout.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT));

//add shadow
shadowImageView = new ImageView(this);
shadowImageView.setBackgroundResource(R.drawable.shadow);
shadowImageView.setLayoutParams(new LinearLayout.LayoutParams(shadowWidth, LinearLayout.LayoutParams.MATCH_PARENT));
containerLayout.addView(shadowImageView);
containerLayout.addView(frameLayout);
containerLayout.setTranslationX(-shadowWidth);
//添加两个view
slidingPaneLayout.addView(behindframeLayout, 0);
slidingPaneLayout.addView(containerLayout, 1);
}

@Override
public void setContentView(int id) {
setContentView(getLayoutInflater().inflate(id, null));
}

@Override
public void setContentView(View v) {
setContentView(v, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
try {
behindImageView.setScaleType(ImageView.ScaleType.FIT_XY);
behindImageView.setImageBitmap(getBitmap());
} catch (Exception e) {
e.printStackTrace();
}
}

@Override
public void setContentView(View v, ViewGroup.LayoutParams params) {
super.setContentView(slidingPaneLayout, params);
frameLayout.removeAllViews();
frameLayout.addView(v, params);
}

@Override
public void onPanelClosed(View view) {

}

@Override
public void onPanelOpened(View view) {
finish();
this.overridePendingTransition(0, 0);
}

@SuppressLint("NewApi")
@Override
public void onPanelSlide(View view, float v) {
Log.e(TAG, "onPanelSlide ：" + v);
//duang duang duang 你可以在这里加入很多特效
behindImageView.setTranslationX(v * defaultTranslationX - defaultTranslationX);
shadowImageView.setAlpha(v<0.8?1:(1.5f-v));
}

/**
* 取得视觉差背景图
*
* @return
*/
public Bitmap getBitmap() {
return BitmapFactory.decodeFile(mFileTemp.getAbsolutePath());
}

/**
* 启动视觉差返回Activity
*
* @param activity
* @param intent
*/
public void startParallaxSwipeBackActivty(Activity activity, Intent intent) {
startParallaxSwipeBackActivty(activity, intent, false);
}

/**
* startParallaxSwipeBackActivty
*
* @param activity
* @param intent
* @param isFullScreen
*/
public void startParallaxSwipeBackActivty(Activity activity, Intent intent, boolean isFullScreen) {
screenshots(activity, isFullScreen);
startActivity(intent);
this.overridePendingTransition(R.anim.slide_in_right, R.anim.slide_out_right);
}

/**
* this screeshots form
*
* @param activity
* @param isFullScreen
*/
public void screenshots(Activity activity, boolean isFullScreen) {
try {
//View是你需要截图的View
View decorView = activity.getWindow().getDecorView();
decorView.setDrawingCacheEnabled(true);
decorView.buildDrawingCache();
Bitmap b1 = decorView.getDrawingCache();
// 获取状态栏高度 /
Rect frame = new Rect();
activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
int statusBarHeight = frame.top;
Log.e(TAG, "statusBarHeight:" + statusBarHeight);
// 获取屏幕长和高 Get screen width and height
int width = activity.getWindowManager().getDefaultDisplay().getWidth();
int height = activity.getWindowManager().getDefaultDisplay().getHeight();
// 去掉标题栏 Remove the statusBar Height
Bitmap bitmap;
if (isFullScreen) {
bitmap = Bitmap.createBitmap(b1, 0, 0, width, height);
} else {
bitmap = Bitmap.createBitmap(b1, 0, statusBarHeight, width, height - statusBarHeight);
}
decorView.destroyDrawingCache();
FileOutputStream out = new FileOutputStream(mFileTemp);
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out);
} catch (Exception e) {
e.printStackTrace();
}
}

/**
* 根据手机的分辨率从 dip 的单位 转成为 px(像素)
*/
public int dip2px(float dpValue) {
final float scale = getResources().getDisplayMetrics().density;
return (int) (dpValue * scale + 0.5f);
}
}

资源文件：

anim

slide_in_right.xml

<?xml version="1.0" encoding="utf-8"?>
<set
xmlns:android="http://schemas.android.com/apk/res/android"
android:shareInterpolator="false"
android:zAdjustment="top">
<translate
android:duration="200"
android:fromXDelta="100.0%p"
android:toXDelta="0.0" />
</set>

slide_out_right.xml

<?xml version="1.0" encoding="utf-8"?>
<set
xmlns:android="http://schemas.android.com/apk/res/android"
android:shareInterpolator="false"
android:zAdjustment="top">
<translate
android:duration="200"
android:fromXDelta="0.0"
android:toXDelta="100.0%p" />
</set>

drawable



使用方法很简单，当前类继成ParallaxSwipeBackActivity就好了

源码地址：https://github.com/bushijie/ParallaxSwipeBack