Android加载离线和网络git

本文介绍如何将android-gif-drawable集成到项目中，并且如何使用android-gif-drawable加载离线和网络Gif动图。

android-gif-drawable的集成

在线集成

Github上相关教程，也比较简单，将依赖添加到项目的build.gradle文件即可：

dependencies {

    compile 'pl.droidsonroids.gif:android-gif-drawable:1.2.11'

}

离线集成

Android Studio 3.0中有效

1. 
   

2. 进入Github上的realease页面-realease点我

   
   

3. 下载其中的android-gif-drawable-1.2.11.aar

   
   

4. 将android-gif-drawable-1.2.11.aar添加到项目的libs目录中

   
   

5. 在项目的build.gradle中添加该arr文件

   
   

compile(name:'android-gif-drawable-1.2.11', ext:'aar')

1. 
   
2. 集成完毕，可以进行测试。
   

android-gif-drawable的使用

android-gif-drawable有四种控件：GifImageView、GifImageButton、GifTextView、GifTextureView。这里以ImageView为例进行介绍。

加载本地图片

1. 
   
2. 直接在布局中选定资源文件
   

<pl.droidsonroids.gif.GifImageView
    android:id="@+id/fragment_gif_local"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/dog"/>

1. 
   
2. 通过代码进行动态添加gif动图
   

//1. 构建GifDrawable

GifDrawable gifFromResDrawable = new GifDrawable( getResources(), R.drawable.dog );
//2. 设置给GifImageView控件

gifImageView.setImageDrawable(gifFromResDrawable);

GifDrawable

GifDrawable是用于该开源库的Drawable类。构造方法大致有9种：

//1. asset file

GifDrawable gifFromAssets = new GifDrawable( getAssets(), "anim.gif" );

//2. resource (drawable or raw)

GifDrawable gifFromResource = new GifDrawable( getResources(), R.drawable.anim );

//3. byte array
byte[] rawGifBytes = ...

GifDrawable gifFromBytes = new GifDrawable( rawGifBytes );

//4. FileDescriptor

FileDescriptor fd = new RandomAccessFile( "/path/anim.gif", "r" ).getFD();

GifDrawable gifFromFd = new GifDrawable( fd );

//5. file path

GifDrawable gifFromPath = new GifDrawable( "/path/anim.gif" );

//6. file

File gifFile = new File(getFilesDir(),"anim.gif");

GifDrawable gifFromFile = new GifDrawable(gifFile);

//7. AssetFileDescriptor

AssetFileDescriptor afd = getAssets().openFd( "anim.gif" );

GifDrawable gifFromAfd = new GifDrawable( afd );

//8. InputStream (it must support marking)

InputStream sourceIs = ...

BufferedInputStream bis = new BufferedInputStream( sourceIs, GIF_LENGTH );

GifDrawable gifFromStream = new GifDrawable( bis );

//9. direct ByteBuffer

ByteBuffer rawGifBytes = ...

GifDrawable gifFromBytes = new GifDrawable( rawGifBytes );

加载网络Gif

我们解决的办法是将Gif图片下载到缓存目录中，然后从磁盘缓存中获取该Gif动图进行显示。

1、下载工具DownloadUtils.java

public class DownloadUtils {
private final int DOWN_START = 1; // Handler消息类型(开始下载)
private final int DOWN_POSITION = 2; // Handler消息类型(下载位置)
private final int DOWN_COMPLETE = 3; // Handler消息类型(下载完成)
private final int DOWN_ERROR = 4; // Handler消息类型(下载失败)
private OnDownloadListener onDownloadListener;

public void setOnDownloadListener(OnDownloadListener onDownloadListener) {
this.onDownloadListener = onDownloadListener;

    }

/**

     * 下载文件

     *

     * @param url      文件路径

     * @param filepath 保存地址

     */
public void download(String url, String filepath) {

        MyRunnable mr = new MyRunnable();

        mr.url = url;

        mr.filepath = filepath;
new Thread(mr).start();

    }

@SuppressWarnings("unused")
private void sendMsg(int what) {

        sendMsg(what, null);

    }

private void sendMsg(int what, Object mess) {

        Message m = myHandler.obtainMessage();

        m.what = what;

        m.obj = mess;

        m.sendToTarget();

    }


    Handler myHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case DOWN_START: // 开始下载
int filesize = (Integer) msg.obj;

                    onDownloadListener.onDownloadConnect(filesize);
break;
case DOWN_POSITION: // 下载位置
int pos = (Integer) msg.obj;

                    onDownloadListener.onDownloadUpdate(pos);
break;
case DOWN_COMPLETE: // 下载完成

                    String url = (String) msg.obj;

                    onDownloadListener.onDownloadComplete(url);
break;
case DOWN_ERROR: // 下载失败

                    Exception e = (Exception) msg.obj;

                    e.printStackTrace();

                    onDownloadListener.onDownloadError(e);
break;

            }
super.handleMessage(msg);

        }

    };


    class MyRunnable implements Runnable {
private String url = "";
private String filepath = "";

@Override
public void run() {
try {

                doDownloadTheFile(url, filepath);

            } catch (Exception e) {

                sendMsg(DOWN_ERROR, e);

            }

        }

    }

/**

     * 下载文件

     *

     * @param url      下载路劲

     * @param filepath 保存路径

     * @throws Exception

     */
private void doDownloadTheFile(String url, String filepath) throws Exception {
if (!URLUtil.isNetworkUrl(url)) {

            sendMsg(DOWN_ERROR, new Exception("不是有效的下载地址：" + url));
return;

        }

        URL myUrl = new URL(url);

        URLConnection conn = myUrl.openConnection();

        conn.connect();

        InputStream is = null;
int filesize = 0;
try {

            is = conn.getInputStream();

            filesize = conn.getContentLength();// 根据响应获取文件大小

            sendMsg(DOWN_START, filesize);

        } catch (Exception e) {

            sendMsg(DOWN_ERROR, new Exception(new Exception("无法获取文件")));
return;

        }

        FileOutputStream fos = new FileOutputStream(filepath); // 创建写入文件内存流，
// 通过此流向目标写文件
byte buf[] = new byte[1024];
int numread = 0;
int temp = 0;
while ((numread = is.read(buf)) != -1) {

            fos.write(buf, 0, numread);

            fos.flush();

            temp += numread;

            sendMsg(DOWN_POSITION, temp);

        }

        is.close();

        fos.close();

        sendMsg(DOWN_COMPLETE, filepath);

    }


    interface OnDownloadListener{
public void onDownloadUpdate(int percent);

public void onDownloadError(Exception e);

public void onDownloadConnect(int filesize);

public void onDownloadComplete(Object result);

    }

}

2、调用DonwloadUtils进行下载，下载完成后加载本地图片

//1. 下载gif图片(文件名自定义可以通过Hash值作为key)

DownloadUtils downloadUtils = new DownloadUtils();

downloadUtils.download(gifUrlArray[0],

                getDiskCacheDir(getContext())+"/0.gif");
//2. 下载完毕后通过“GifDrawable”进行显示

downloadUtils.setOnDownloadListener(new DownloadUtils.OnDownloadListener() {
@Override
public void onDownloadUpdate(int percent) {

            }
@Override
public void onDownloadError(Exception e) {

            }
@Override
public void onDownloadConnect(int filesize) {

            }
//下载完毕后进行显示
@Override
public void onDownloadComplete(Object result) {
try {

                    GifDrawable gifDrawable = new GifDrawable(getDiskCacheDir(getContext())+"/0.gif");

                    mGifOnlineImageView.setImageDrawable(gifDrawable);

                } catch (IOException e) {

                    e.printStackTrace();

                }

            }

        });

//获取缓存的路径
public String getDiskCacheDir(Context context) {

    String cachePath = null;
if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())

            || !Environment.isExternalStorageRemovable()) {
// 路径：/storage/emulated/0/Android/data/<application package>/cache

        cachePath = context.getExternalCacheDir().getPath();

    } else {
// 路径：/data/data/<application package>/cache

        cachePath = context.getCacheDir().getPath();

    }
return cachePath;

}

github地址：https://github.com/koral--/android-gif-drawable

转载请注明链接：http://blog.csdn.net/feather_wch/article/details/79558240