Android 无法将图像从sd卡加载到gridview

嗨，我想把从相机拍摄的所有图像加载到网格视图中。但我有一个奇怪的例外。如果我只是尝试加载2或3个图像，所有的都进行得很顺利，但是当我尝试加载所有图像时，出现了错误。我的

SD卡中大约有20个图像。这是我的代码

package com.example.imagegridview;

import java.io.File;
import java.util.ArrayList;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Menu;
import android.widget.GridView;
import android.widget.Toast;

@SuppressLint("NewApi")
public class MainActivity extends Activity {

    ArrayList<Bitmap> data;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        String sdCardRootPath = Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_DCIM).toString()+"/Camera";
        File rootFolder = new File(sdCardRootPath);
        File[] picFiles = rootFolder.listFiles();
        data = new ArrayList<Bitmap>();
        for (File pic:picFiles) {
            Bitmap b= BitmapFactory.decodeFile(pic.getAbsolutePath());
            data.add(b);
        }
        GridView gv = (GridView) findViewById(R.id.gridview);
        gv.setAdapter(new MAdapter(this,data));

    }

}

你可能需要检查一下这个文件

我建议在直接添加图像之前，先缩放每个图像。
来自相机的图像实际上是一个相当大的尺寸，当你尝试添加20个这样的图像时，它肯定会在移动设备上溢出。
因此，在上传之前，请缩放每个图像，并确保其正常工作。
在加载ie之前，请先调整位图大小，然后使用下面的代码对位图进行解码。`

     public Bitmap decodeFile(File f, int size) {

            try {
        // decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(new FileInputStream(f), null, o);

        // Find the correct scale value. It should be the power of 2.
        final int REQUIRED_SIZE = size;
        int width_tmp = o.outWidth, height_tmp = o.outHeight;
        int scale = 1;
        while (true) {
            if (width_tmp / 2 < REQUIRED_SIZE
                    || height_tmp / 2 < REQUIRED_SIZE)
                break;
            width_tmp /= 2;
            height_tmp /= 2;
            scale *= 2;
        }

        // decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        o2.outWidth = width_tmp;
        o2.outHeight = height_tmp;
        return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
    } catch (FileNotFoundException e) {
    }
    return null;
}`

公共位图解码文件（文件f，int size）{
试一试{
//解码图像大小
BitmapFactory.Options o=新的BitmapFactory.Options（）；
o、 inJustDecodeBounds=true；
解码流（新的FileInputStream（f），null，o）；
//找到正确的刻度值。它应该是2的幂。
所需最终整型尺寸=尺寸；
内部宽度=o.向外宽度，高度=o.向外高度；
int标度=1；
while（true）{
如果（宽度\u tmp/2<要求的\u尺寸
||高度（tmp/2<所需尺寸）
打破
宽度_tmp/=2；
高度_tmp/=2；
比例*=2；
}
//用inSampleSize解码
BitmapFactory.Options o2=新的BitmapFactory.Options（）；
o2.inSampleSize=刻度；
o2.outWidth=宽度\u tmp；
o2.outHeight=高度\u tmp；
返回BitmapFactory.decodeStream（新文件输入流（f），null，o2）；
}catch（filenotfounde异常）{
}
返回null；
}`

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent" 
    android:orientation="vertical">
<GridView
    android:id="@+id/gridview"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
    android:columnWidth="90dp"
    android:numColumns="auto_fit"
    android:verticalSpacing="10dp"
    android:horizontalSpacing="10dp"
    android:stretchMode="columnWidth"
    android:gravity="center"/>

</LinearLayout>

03-13 23:39:22.632: E/AndroidRuntime(13228): java.lang.OutOfMemoryError: bitmap size exceeds VM budget
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:562)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:371)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:399)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at com.example.imagegridview.MainActivity.onCreate(MainActivity.java:32)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2633)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2685)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.app.ActivityThread.access$2300(ActivityThread.java:126)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2038)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.os.Handler.dispatchMessage(Handler.java:99)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.os.Looper.loop(Looper.java:123)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at android.app.ActivityThread.main(ActivityThread.java:4633)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at java.lang.reflect.Method.invokeNative(Native Method)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at java.lang.reflect.Method.invoke(Method.java:521)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
03-13 23:39:22.632: E/AndroidRuntime(13228):    at dalvik.system.NativeStart.main(Native Method)

     public Bitmap decodeFile(File f, int size) {

            try {
        // decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(new FileInputStream(f), null, o);

        // Find the correct scale value. It should be the power of 2.
        final int REQUIRED_SIZE = size;
        int width_tmp = o.outWidth, height_tmp = o.outHeight;
        int scale = 1;
        while (true) {
            if (width_tmp / 2 < REQUIRED_SIZE
                    || height_tmp / 2 < REQUIRED_SIZE)
                break;
            width_tmp /= 2;
            height_tmp /= 2;
            scale *= 2;
        }

        // decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        o2.outWidth = width_tmp;
        o2.outHeight = height_tmp;
        return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
    } catch (FileNotFoundException e) {
    }
    return null;
}`