android 已省内存方式把图片加载到内存
这里，有个异步处理图片的方法，我直接把我这个类复制粘贴进来。注意内存要及时回收。android内存比较局限。
<span style="font-size:14px;">package com.commons.utils.image;
import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.*;
import android.os.Build;
import android.util.Log;
import com.commons.config.GlobalConfig;
import com.commons.utils.memory.MemoryUtils;
import java.io.*;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
/**
* 从DrawableUtil类中分离出来这个类,为了使代码看起来更加简洁明了
* 用于Bitmap处理的一些方法
*/
public class BitmapUtils {
public static final int ARGB8888_MODEL=4;//ARGB8888模式下消耗内存,为像素数乘以4个字节.
public static final int RGB565_MODEL=2;//RGB565模式下消耗内存,为像素数乘以4个字节.
/**
* 获取APP剩余可申请内存,判断是否够大,以手机分辨率为基础,进行计算图片处理所需要消耗的内存.
* @return
*
* !!!这里获取的不是手机的剩余内存而是APP的
*/
public static boolean isBigSurpluseMemory(Context context)
{
boolean isbig=true;//默认
long appsurplusMe= MemoryUtils.getAppSurplusMe();//这里单位是Byte
long phonesurplusMe= MemoryUtils.getPhoneSurplusMe(context);//这里单位是Byte
long bitmapoptNeedmemory=GlobalConfig.scrwid*GlobalConfig.scrhei*ARGB8888_MODEL;//单位依旧是Byte
//在进行图片处理的时候会把图片分辨率缩小到屏幕分辨率大小,所以这里消耗内存的计算是以屏幕分辨率所谓基础的.
if(bitmapoptNeedmemory*2 > appsurplusMe)//为了其他考虑,剩余内存应该大于所需要内存的两倍
{
return false;
}
if(bitmapoptNeedmemory*2>phonesurplusMe)
{
return false;
}//这里一定要判断手机剩余内存,上面的判断只是app的理论上的内存限制,而如果手机本身就已经没有内存了,
// 会有两种情况 1.自动清理一些内存 来给当前app用,2.本身就是内存太小,现在占内存的应用都是系统级别的清理不掉,那就坑了
// 举个例子：125M内存的手机上就会发生当手机时，我发现内存不够的时候，android的自动杀进程的机制就没法用了
//请看如下的我在410M的手机上运行的结果
return isbig;
}
/**
12-11 16:52:35.260 441-441/com.jsdx.zqysypt D/MemoryUtils.printMemoryInfo()﹕ 常规应用最大内存限制:64M 流氓应用最大内存限制:128M
12-11 16:52:35.270 441-441/com.jsdx.zqysypt D/MemoryUtils.printMemoryInfo()﹕ APP当前内存状态: 最大可申请内存:128MB 已申请内存:21MB 空闲内存:4MB
12-11 16:52:35.270 441-441/com.jsdx.zqysypt D/MemoryUtils.printMemoryInfo()﹕ 手机剩余内存:70.12109MB 手机总内存:410.54297MB
这里可以明显看出app剩余可申请的内存要大于手机的剩余内存的.当申请更多内存的时候android就会自动清理
*/
/**
* 创建倒影图片
* @throws IOException
*/
public static Bitmap createReflectedBitmap(Bitmap srcBitmap) {
if (null == srcBitmap) {
return null;
}
// The gap between the reflection bitmap and original bitmap.
final int REFLECTION_GAP = 4;
int srcWidth = srcBitmap.getWidth();
int srcHeight = srcBitmap.getHeight();
int reflectionWidth = srcBitmap.getWidth();
int reflectionHeight = srcBitmap.getHeight() / 2;
if (0 == srcWidth || srcHeight == 0) {
return null;
}
// The matrix
Matrix matrix = new Matrix();
matrix.preScale(1, -1);
try {
// The reflection bitmap, width is same with original's, height is half of original's.
Bitmap reflectionBitmap = Bitmap.createBitmap(
srcBitmap,
0,
srcHeight / 2,
srcWidth,
srcHeight / 2,
matrix,
false);
if (null == reflectionBitmap) {
return null;
}
// Create the bitmap which contains original and reflection bitmap.
Bitmap bitmapWithReflection = Bitmap.createBitmap(
reflectionWidth,
srcHeight + reflectionHeight + REFLECTION_GAP,
Bitmap.Config.ARGB_8888);
if (null == bitmapWithReflection) {
return null;
}
// Prepare the canvas to draw stuff.
Canvas canvas = new Canvas(bitmapWithReflection);
// Draw the original bitmap.
canvas.drawBitmap(srcBitmap, 0, 0, null);
// Draw the reflection bitmap.
canvas.drawBitmap(reflectionBitmap, 0, srcHeight + REFLECTION_GAP, null);
Paint paint = new Paint();
paint.setAntiAlias(true);
LinearGradient shader = new LinearGradient(
0,
srcHeight,
0,
bitmapWithReflection.getHeight() + REFLECTION_GAP,
0x70FFFFFF,
0x00FFFFFF,
Shader.TileMode.MIRROR);
paint.setShader(shader);
paint.setXfermode(new PorterDuffXfermode(android.graphics.PorterDuff.Mode.DST_IN));
// Draw the linear shader.
canvas.drawRect(
0,
srcHeight,
srcWidth,
bitmapWithReflection.getHeight() + REFLECTION_GAP,
paint);
return bitmapWithReflection;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public static Bitmap revitionImageSize(String path, int max_w, int max_h) throws IOException {
BufferedInputStream in = new BufferedInputStream(new FileInputStream(
new File(path)));
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(in, null, options);
in.close();
int i = 0;
Bitmap bitmap = null;
while (true) {
if ((options.outWidth >> i <= max_w)
&& (options.outHeight >> i <= max_h)) {
in = new BufferedInputStream(
new FileInputStream(new File(path)));
options.inSampleSize = (int) Math.pow(2.0D, i);
options.inJustDecodeBounds = false;
bitmap = BitmapFactory.decodeStream(in, null, options);
break;
}
i += 1;
}
return bitmap;
}
/**
*将Bitmap保存到本地
* @param bitmap
* @param imgurl imgurl 不带file了开头的路径,如: /strange/sdcard/asdasd.jpg
*/
public static void savePictureToLocal(Bitmap bitmap, String imgurl) {
FileOutputStream b = null;
File file = new File(imgurl);
file.getParentFile().mkdirs();// 创建文件夹
//对图片质量进行压缩,这样保存的图片就变小了
int yasuolv = 60;
try {
b = new FileOutputStream(imgurl);
bitmap.compress(Bitmap.CompressFormat.JPEG, yasuolv, b);// 把数据写入文件
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
try {
b.flush();
b.close();
//bitmap.recycle();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 得到本地或者网络上的bitmap url - 网络或者本地图片的绝对路径,比如:
* <p/>
* A.网络路径: url="http://blog.foreverlove.us/girl2.png" ;
* <p/>
* B.本地路径:url="mnt/sdcard/photo/image.png"; 不带 file: 头
* <p/>
* C.支持的图片格式 ,png, jpg,bmp,gif等等
*
* @param path
* @return
*/
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR1)
public static Bitmap GetLocalOrNetBitmap(String path) {
final String TAG="GetLocalOrNetBitmap";
Bitmap bitmap = null;
try {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
bitmap = BitmapFactory.decodeFile(path, options); //此时返回 bm 为空
options.inJustDecodeBounds = false; //缩放比。由于是固定比例缩放，只用高或者宽其中一个数据进行计算即可
int hi = (int) (options.outHeight / (float) GlobalConfig.scrhei);//以屏幕高度作为显示依据
int wi = (int) (options.outWidth / (float) GlobalConfig.scrwid);//以屏幕高度作为显示依据
int be = 0;
if (wi > hi)
be = hi;
else
be = wi;
Log.d(TAG, "缩放比:"+be); //缩放之后
Log.d(TAG, "原图宽高:"+options.outWidth+" "+options.outHeight); //缩放之后
if (be <= 0)
be = 1;
options.inSampleSize = be; //重新读入图片，注意此时已经把 options.inJustDecodeBounds 设回 false 了
options.inPreferredConfig = Bitmap.Config.RGB_565;//使用RGB_565后会是内存降低一半但是,不适合decode带有透明区域的PNG
bitmap = BitmapFactory.decodeFile(path, options);
int w = bitmap.getWidth();
int h = bitmap.getHeight();
Log.d(TAG, "缩放后:宽"+w + " 高" + h); //缩放之后
Log.d(TAG, "RGB_565格式内存:"+bitmap.getByteCount() / 1024 + "KB");
}
catch (Exception ex)
{
if(bitmap!=null&&!bitmap.isRecycled())
bitmap.recycle();
System.gc(); //提醒系统及时回收
}
return bitmap;
}
//同上,最后一个参数可选,配置是否返回高色彩的Bitmap
//本地路径 不带 file: 头
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR1)
public static Bitmap GetLocalOrNetBitmap(String path, boolean isRGb_565) {
final String TAG="GetLocalOrNetBitmap";
Bitmap bitmap = null;
try {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
bitmap = BitmapFactory.decodeFile(path, options); //此时返回 bm 为空
options.inJustDecodeBounds = false; //缩放比。由于是固定比例缩放，只用高或者宽其中一个数据进行计算即可
int hi = (int) (options.outHeight / (float) GlobalConfig.scrhei);//以屏幕高度作为显示依据
int wi = (int) (options.outWidth / (float) GlobalConfig.scrwid);//以屏幕高度作为显示依据
int be = 0;
if (wi > hi)
be = hi;
else
be = wi;
Log.d(TAG, "缩放比:"+be); //缩放之后
Log.d(TAG, "原图宽高:"+options.outWidth+" "+options.outHeight); //缩放之后
if (be <= 0)
be = 1;
options.inSampleSize = be; //重新读入图片，注意此时已经把 options.inJustDecodeBounds 设回 false 了
if(isRGb_565)
options.inPreferredConfig = Bitmap.Config.RGB_565;//使用RGB_565后会是内存降低一半但是,不适合decode带有透明区域的PNG
bitmap = BitmapFactory.decodeFile(path, options);
int w = bitmap.getWidth();
int h = bitmap.getHeight();
Log.d(TAG, "缩放后:宽" + w + " 高" + h); //缩放之后
Log.d(TAG, "RGB_565格式内存:"+bitmap.getByteCount() / 1024 + "KB");
}
catch (Exception ex)
{
if(bitmap!=null&&!bitmap.isRecycled())
bitmap.recycle();
System.gc(); //提醒系统及时回收
}
return bitmap;
}
//同上,最后一个参数可选,配置是否返回高色彩的Bitmap
//本地路径 不带 file: 头
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR1)
public static Bitmap GetLocalOrNetBitmap(String path, boolean isRGb_565,int maxwidth,int maxheight) {
final String TAG="GetLocalOrNetBitmap";
Bitmap bitmap = null;
try {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
Log.d("GetLocalOrNetBitmap",path);
bitmap = BitmapFactory.decodeFile(path, options); //此时返回 bm 为空
options.inJustDecodeBounds = false; //缩放比。由于是固定比例缩放，只用高或者宽其中一个数据进行计算即可
int hi = (int) (options.outHeight / (float) maxwidth);//以指定宽度作为显示依据
int wi = (int) (options.outWidth / (float) maxheight);//以指定高度作为显示依据
int be = 0;
if (wi < hi)
be = hi;
else
be = wi;
Log.d(TAG, "缩放比:"+be); //缩放之后
Log.d(TAG, "原图宽高:"+options.outWidth+" "+options.outHeight); //缩放之后
if (be <= 0)
be = 1;
options.inSampleSize = be; //重新读入图片，注意此时已经把 options.inJustDecodeBounds 设回 false 了
if(isRGb_565)
options.inPreferredConfig = Bitmap.Config.RGB_565;//使用RGB_565后会是内存降低一半但是,不适合decode带有透明区域的PNG
bitmap = BitmapFactory.decodeFile(path, options);
int w = bitmap.getWidth();
int h = bitmap.getHeight();
Log.d(TAG, "缩放后:宽" + w + " 高" + h); //缩放之后
Log.d(TAG, "RGB_565格式内存:"+bitmap.getByteCount() / 1024 + "KB");
}
catch (Exception ex)
{
if(bitmap!=null&&!bitmap.isRecycled())
bitmap.recycle();
System.gc(); //提醒系统及时回收
}
return bitmap;
}
public static void createPath(String path) {
File file = new File(path);
if (!file.exists()) {
file.mkdir();
}
}
//传递两个参数即可 第一个是bitmap 第二个是目录名称,第二个参数为空时 保存在SD卡上
public static void saveMyBitmap(Bitmap bmp, String directory, String filename) {
String direc = "";
if (directory.length() < 1) {
direc = GlobalConfig.sdPath + "/";
} else {
direc = GlobalConfig.sdPath + "/" + directory + "/";
createPath(direc);
}
File f = null;
if (filename.length() < 1) {
try {
Date date = new Date();
DateFormat format = new SimpleDateFormat("yyyy-MM-dd HH_mm_ss_");
filename = "www.njoki.com__" + format.format(date);
} catch (Exception e) {
filename = "未知";
}
f = new File(direc + filename + ".png");
} else {
f = new File(direc + filename + ".png");
}
FileOutputStream fOut = null;
try {
f.createNewFile();
fOut = new FileOutputStream(f);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
//Bitmap bitmap = ((BitmapDrawable)mImageView.getDrawable()).getBitmap();
//bitmap.compress(Bitmap.CompressFormat.PNG, 100, fOut);
bmp.compress(Bitmap.CompressFormat.PNG, 100, fOut);
try {
fOut.flush();
} catch (IOException e) {
e.printStackTrace();
}
try {
fOut.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}</span>
//上log
12-11 10:10:18.429 9782-9782/com.oki.lyw.activity D/lessenUriImage﹕ 缩放比:3
12-11 10:10:18.429 9782-9782/com.oki.lyw.activity D/lessenUriImage﹕ 原图宽高:3920 2204
12-11 10:10:18.870 9782-9782/com.oki.lyw.activity D/lessenUriImage﹕ 缩放后:宽1960 高1102
12-11 10:10:18.870 9782-9782/com.oki.lyw.activity D/lessenUriImage﹕ 内存:8437KB
12-11 10:14:39.684 12101-12101/com.oki.lyw.activity D/lessenUriImage﹕ 缩放比:3
12-11 10:14:39.684 12101-12101/com.oki.lyw.activity D/lessenUriImage﹕ 原图宽高:3920 2204
12-11 10:14:40.115 12101-12101/com.oki.lyw.activity D/lessenUriImage﹕ 缩放后:宽1960 高1102
12-11 10:14:40.115 12101-12101/com.oki.lyw.activity D/lessenUriImage﹕ RGB_565格式内存:4218KB
12-11 10:14:40.635 12101-12101/com.oki.lyw.activity D/imageloader消耗内存﹕ 4218KB
//从上面可以看出使用imageloader和我的这个方法消耗的内存是一致的
//上图
while(true) {
Runtime rt = Runtime.getRuntime();
try {
bitlist.add(BitmapUtils.lessenUriImage(input));
bitlist.add(BitmapUtils.lessenUriImage(input));
Log.d("TAG", "系统当前内存状态:已申请内存:" + rt.totalMemory() / 1024 + "KB 最大可申请内存:" + rt.maxMemory() / 1024 + "KB");
} catch (OutOfMemoryError error) {
Log.d("TAG", "系统当前内存状态:已申请内存:" + rt.totalMemory() / 1024 + "KB 最大可申请内存:" + rt.maxMemory() / 1024 + "KB"+" 空闲内存:"+rt.freeMemory()/1024+"KB");
Log.d("内存", "OOM了");
break;
}
};
bitlist=null;
System.gc();
if(true)
return ;