显示Android的巨大图片 [英] display huge Images in Android

问题描述

我打算在Android中显示的图像非常大。

我的第一个解决方案 - 以供应为PDF - 失败，因为不是每个手持得到的PDF阅读器preinstalled，我不想要求用户安装一。

I'm intending to display very large Images in Android.

My first solution - to supply them as pdf - fails because not every handheld got a pdf-viewer preinstalled, and I don't want to require the users to install one.

所以我有一个PNG现在的（宽度= 3998px高度= 2827px）我要显示。我下载了这个形象来测试它会显示在画廊。这是相当痛苦的。看来，galery呈现此画面只有一次，如果我放大，我看​​不懂的文字都没有。

所以我写了testActivity它只是有嵌套在一个LinearLayout中的ImageView的。我把图像转换成可绘制，并将其设置为ImageView的形象来源。 Unforunately应用程序崩溃立刻，由于一个

So I have a png now (width = 3998px height=2827px) that I want to display. I downloaded this image to test how it would be displayed the gallery. It was quite painful. It seems that the galery renders this picture only once, and if I Zoom in, I cannot read the text at all.

So I wrote a testActivity which simply has an ImageView nested in a LinearLayout. I put the image into the drawable and set it as ImageView's image-source. Unforunately the app crashes immediatly, due to an "

 ERROR/AndroidRuntime(8906): Caused by: java.lang.OutOfMemoryError: bitmap size exceeds VM budget"  

我没想到的是一个单一的图像可以太大虚拟机的内存。我打得有点绕，设置 ImageViews 大小 3998及放大器; 2827px ，把图像到 SD卡和手动读取它的FileInputStream 。
为了我的大惊喜，现在显示了我的形象，但如果我把我的 Nexus S的水平我得到同样的的OutOfMemoryError 和以前一样。照片< BR> recieving通过的FileInputStream A位图之间可以somewone点我的主要区别，或将其设置为的ImageView 来源。

另外，我无法滚动的舒适与两家母公司 scrollViews

我寻找一个简单的解决方案，以显示一个大图像在与能力滚动水平和垂直同时能够一次为放大和缩小。

I didn't expect that ONE single Image can be too large forVM's memory. I played a little bit around, set ImageViews size to 3998 & 2827px , put the Image to sdCard and read it manually with a fileInputStream.
To my big surprise it now shows my image, but if I turn my Nexus S horizontal I get the same OutOfMemoryError as before.

Can somewone point me the main difference between recieving a Bitmap through a FileInputStream or to set it as ImageView's source.

Also I'm not able to scroll comfortable with two parent scrollViews

I searching for a simple solution to display ONE large image at a time with the ability to scroll horizontal and vertical while able to zoom in and out.

下面是图片的我想显示的样本

here is a sample of the image I want to display

推荐答案

我知道这是一个老的文章，但我花了很多时间在这个问题上，所以这里是我的解决方案。

I know it's an old post but I spent a lot of time on this problem, so here's my solution.

我想显示2000×3000的图片，但我离开了内存或图片过大，无法显示。

I wanted to display a 2000×3000 picture but I got out of memory or the image was too large to be displayed.

首先，我得到的图片的尺寸：

To begin, I get the dimensions of the picture:

o = new BitmapFactory.Options();
o.inJustDecodeBounds=true;
pictures = BitmapFactory.decodeStream(new FileInputStream(f), null, o);

然后我将它分成四个部分，并用四个ImageViews显示它们。 我试图加载的完整画面，并把它切成四（使用 BitmapFactory.create（位图，INT，INT，INT，INT）），但得到的内存不足了。

Then I cut it up into four parts and displayed them with four ImageViews. I tried to load the full picture and cut it into four (using BitmapFactory.create(bitmap,int,int,int,int)) but got out of memory again.

所以，我决定用一些BitMa pregionDe codeR：

So I decided to use some BitMapRegionDecoder:

for (int i = 0; i < 2; i++) {
    for (int j = 0; j < 2; j++) {
        ImageView iv = new ImageView(this);         
        InputStream istream =   null;
        try {
         istream = this.getContentResolver().openInputStream(Uri.fromFile(f));
        } catch (FileNotFoundException e1) {
         e1.printStackTrace();
        }
        BitmapRegionDecoder decoder     =   null;
        try {
        decoder = BitmapRegionDecoder.newInstance(istream, false);
        } catch (IOException e) {
                    e.printStackTrace();
        }
    int nw = (j*width/k);
    int nh = (i*height/k);

    Bitmap bMap = decoder.decodeRegion(new Rect(nw,nh, (nw+width/k),(nh+height/k)), null);    
    iv.setImageBitmap(bMap);

    }
}

这工作。

这篇关于显示Android的巨大图片的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！