Utils.java

package com.example.administrator.searchpicturetool.util;
import android.content.Context;
import android.content.Intent;
import android.content.res.Resources;
import android.net.Uri;
import android.os.Environment;
import android.view.KeyCharacterMap;
import android.view.KeyEvent;
import android.view.ViewConfiguration;

import com.example.administrator.searchpicturetool.app.APP;
import java.io.File;
import java.lang.reflect.Method;

/**
 * Created by wenhuaijun on 2015/11/7 0007.
 */
public class Utils {
    public static String getSDPath(){
        File sdDir;
        boolean sdCardExist = Environment.getExternalStorageState()
                .equals(android.os.Environment.MEDIA_MOUNTED); //判断sd卡是否存在
        if (sdCardExist)
        {
            sdDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);//获取图片目录
        }else {
            sdDir =  APP.getInstance().getFilesDir();
        }
        return sdDir.toString();
    }

    //分享图片
    public  static void  startShareImg(String path,Context context){
        Intent shareIntent = new Intent(Intent.ACTION_SEND);
        shareIntent.setType("image/*");
        File file = new File(path);
        Uri uri = Uri.fromFile(file);
        shareIntent.putExtra(Intent.EXTRA_STREAM, uri);
        context.startActivity(Intent.createChooser(shareIntent, "请选择"));
    }

    public static boolean checkDeviceHasNavigationBar(Context activity) {

        //通过判断设备是否有返回键、菜单键(不是虚拟键,是手机屏幕外的按键)来确定是否有navigation bar
        boolean hasMenuKey = ViewConfiguration.get(activity)
                .hasPermanentMenuKey();
        boolean hasBackKey = KeyCharacterMap
                .deviceHasKey(KeyEvent.KEYCODE_BACK);

        if (!hasMenuKey && !hasBackKey) {
            // 没有物理按键则一定有navigationbar，不然怎么退出
            return true;
        }
        //有物理按键依然可能有navigationbar，给华为，魅族跪了。。
        return checkDeviceHasNavigationBarAgain(activity);
    }

    private static boolean checkDeviceHasNavigationBarAgain(Context context) {
        boolean hasNavigationBar = false;
        Resources rs = context.getResources();
        int id = rs.getIdentifier("config_showNavigationBar", "bool", "android");
        if (id > 0) {
            hasNavigationBar = rs.getBoolean(id);
        }
        try {
            Class systemPropertiesClass = Class.forName("android.os.SystemProperties");
            Method m = systemPropertiesClass.getMethod("get", String.class);
            String navBarOverride = (String) m.invoke(systemPropertiesClass, "qemu.hw.mainkeys");
            if ("1".equals(navBarOverride)) {
                hasNavigationBar = false;
            } else if ("0".equals(navBarOverride)) {
                hasNavigationBar = true;
            }
        } catch (Exception e) {
        }

        return hasNavigationBar;

    }

    public static int getNavigationBarHeight(Context context) {
        int navigationBarHeight = 0;
        Resources rs = context.getResources();
        int id = rs.getIdentifier("navigation_bar_height", "dimen", "android");
        if (id > 0 && checkDeviceHasNavigationBar(context)) {
            navigationBarHeight = rs.getDimensionPixelSize(id);
        }
        return navigationBarHeight;
    }


}