Java tutorial
/* * Copyright (c) 2015 PocketHub * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.github.pockethub.util; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.net.Uri; import android.text.Html.ImageGetter; import android.text.TextUtils; import android.util.Base64; import android.util.Log; import android.widget.TextView; import com.alorma.github.sdk.bean.dto.request.RequestMarkdownDTO; import com.alorma.github.sdk.services.content.GetMarkdownClient; import com.bugsnag.android.Bugsnag; import com.github.pockethub.R; import com.github.pockethub.rx.ObserverAdapter; import com.google.inject.Inject; import com.squareup.okhttp.OkHttpClient; import com.squareup.okhttp.Request; import org.eclipse.egit.github.core.RepositoryContents; import org.eclipse.egit.github.core.RepositoryId; import org.eclipse.egit.github.core.service.ContentsService; import java.io.File; import java.io.IOException; import java.util.HashMap; import java.util.List; import java.util.Map; import rx.Observable; import rx.android.schedulers.AndroidSchedulers; import rx.functions.Func1; import rx.schedulers.Schedulers; import static android.util.Base64.DEFAULT; import static android.view.View.GONE; import static android.view.View.VISIBLE; import static java.lang.Integer.MAX_VALUE; import static org.eclipse.egit.github.core.client.IGitHubConstants.HOST_DEFAULT; /** * Getter for an image */ public class HttpImageGetter implements ImageGetter { private static class LoadingImageGetter implements ImageGetter { private final Drawable image; private LoadingImageGetter(final Context context, final int size) { int imageSize = ServiceUtils.getIntPixels(context, size); image = context.getResources().getDrawable(R.drawable.image_loading_icon); image.setBounds(0, 0, imageSize, imageSize); } @Override public Drawable getDrawable(String source) { return image; } } private static boolean containsImages(final String html) { return html.contains("<img"); } private final LoadingImageGetter loading; private final Context context; private final File dir; private final int width; private final Map<Object, CharSequence> rawHtmlCache = new HashMap<>(); private final Map<Object, CharSequence> fullHtmlCache = new HashMap<>(); private final ContentsService service; private final OkHttpClient okHttpClient; /** * Create image getter for context * * @param context * @param service */ @Inject public HttpImageGetter(Context context, ContentsService service) { this.context = context; this.service = service; dir = context.getCacheDir(); width = ServiceUtils.getDisplayWidth(context); loading = new LoadingImageGetter(context, 24); okHttpClient = new OkHttpClient(); } private HttpImageGetter show(final TextView view, final CharSequence html) { if (TextUtils.isEmpty(html)) return hide(view); view.setText(trim(html)); view.setVisibility(VISIBLE); view.setTag(null); return this; } private HttpImageGetter hide(final TextView view) { view.setText(null); view.setVisibility(GONE); view.setTag(null); return this; } //All comments end with "\n\n" removing 2 chars private CharSequence trim(CharSequence val) { if (val.charAt(val.length() - 1) == '\n' && val.charAt(val.length() - 2) == '\n') val = val.subSequence(0, val.length() - 2); return val; } /** * Encode given HTML string and map it to the given id * * @param id * @param html * @return this image getter */ public HttpImageGetter encode(final Object id, final String html) { if (TextUtils.isEmpty(html)) return this; CharSequence encoded = HtmlUtils.encode(html, loading); // Use default encoding if no img tags if (containsImages(html)) { CharSequence currentEncoded = rawHtmlCache.put(id, encoded); // Remove full html if raw html has changed if (currentEncoded == null || !currentEncoded.toString().equals(encoded.toString())) fullHtmlCache.remove(id); } else { rawHtmlCache.remove(id); fullHtmlCache.put(id, encoded); } return this; } /** * Bind text view to HTML string * * @param view * @param html * @param id * @return this image getter */ public HttpImageGetter bind(final TextView view, final String html, final Object id) { if (TextUtils.isEmpty(html)) return hide(view); CharSequence encoded = fullHtmlCache.get(id); if (encoded != null) return show(view, encoded); encoded = rawHtmlCache.get(id); if (encoded == null) { if (!html.matches("<[a-z][\\s\\S]*>")) { RequestMarkdownDTO markdownDTO = new RequestMarkdownDTO(); markdownDTO.text = html; new GetMarkdownClient(markdownDTO).observable().subscribeOn(Schedulers.io()) .observeOn(AndroidSchedulers.mainThread()).subscribe(new ObserverAdapter<String>() { @Override public void onNext(String data) { continueBind(view, data, id); } @Override public void onError(Throwable e) { continueBind(view, html, id); } }); } else { return continueBind(view, html, id); } } return this; } private HttpImageGetter continueBind(final TextView view, final String html, final Object id) { CharSequence encoded = HtmlUtils.encode(html, loading); if (containsImages(html)) rawHtmlCache.put(id, encoded); else { rawHtmlCache.remove(id); fullHtmlCache.put(id, encoded); return show(view, encoded); } if (TextUtils.isEmpty(encoded)) return hide(view); show(view, encoded); view.setTag(id); Observable.just(html).subscribeOn(Schedulers.computation()).map(new Func1<String, CharSequence>() { @Override public CharSequence call(String htmlString) { return HtmlUtils.encode(htmlString, HttpImageGetter.this); } }).observeOn(AndroidSchedulers.mainThread()).subscribe(new ObserverAdapter<CharSequence>() { @Override public void onNext(CharSequence htmlCharSequence) { fullHtmlCache.put(id, htmlCharSequence); if (id.equals(view.getTag())) { show(view, htmlCharSequence); } } }); return this; } /** * Request an image using the contents API if the source URI is a path to a * file already in the repository * * @param source * @return * @throws IOException */ private Drawable requestRepositoryImage(final String source) throws IOException { if (TextUtils.isEmpty(source)) return null; Uri uri = Uri.parse(source); if (!HOST_DEFAULT.equals(uri.getHost())) return null; List<String> segments = uri.getPathSegments(); if (segments.size() < 5) return null; String prefix = segments.get(2); // Two types of urls supported: // github.com/github/android/raw/master/app/res/drawable-xhdpi/app_icon.png // github.com/github/android/blob/master/app/res/drawable-xhdpi/app_icon.png?raw=true if (!("raw".equals(prefix) || ("blob".equals(prefix) && !TextUtils.isEmpty(uri.getQueryParameter("raw"))))) return null; String owner = segments.get(0); if (TextUtils.isEmpty(owner)) return null; String name = segments.get(1); if (TextUtils.isEmpty(name)) return null; String branch = segments.get(3); if (TextUtils.isEmpty(branch)) return null; StringBuilder path = new StringBuilder(segments.get(4)); for (int i = 5; i < segments.size(); i++) { String segment = segments.get(i); if (!TextUtils.isEmpty(segment)) path.append('/').append(segment); } if (TextUtils.isEmpty(path)) return null; List<RepositoryContents> contents = service.getContents(RepositoryId.create(owner, name), path.toString(), branch); if (contents != null && contents.size() == 1) { byte[] content = Base64.decode(contents.get(0).getContent(), DEFAULT); Bitmap bitmap = ImageUtils.getBitmap(content, width, MAX_VALUE); if (bitmap == null) return loading.getDrawable(source); BitmapDrawable drawable = new BitmapDrawable(context.getResources(), bitmap); drawable.setBounds(0, 0, bitmap.getWidth(), bitmap.getHeight()); return drawable; } else return null; } @Override public Drawable getDrawable(final String source) { try { Drawable repositoryImage = requestRepositoryImage(source); if (repositoryImage != null) return repositoryImage; } catch (Exception e) { // Ignore and attempt request over regular HTTP request } try { String logMessage = "Loading image: " + source; Log.d(getClass().getSimpleName(), logMessage); Bugsnag.leaveBreadcrumb(logMessage); Request request = new Request.Builder().get().url(source).build(); com.squareup.okhttp.Response response = okHttpClient.newCall(request).execute(); if (!response.isSuccessful()) throw new IOException("Unexpected response code: " + response.code()); Bitmap bitmap = BitmapFactory.decodeStream(response.body().byteStream()); if (bitmap == null) return loading.getDrawable(source); BitmapDrawable drawable = new BitmapDrawable(context.getResources(), bitmap); drawable.setBounds(0, 0, bitmap.getWidth(), bitmap.getHeight()); return drawable; } catch (IOException e) { Log.e(getClass().getSimpleName(), "Error loading image", e); Bugsnag.notify(e); return loading.getDrawable(source); } } /** * Remove Object from cache store. * @param id */ public void removeFromCache(final Object id) { rawHtmlCache.remove(id); fullHtmlCache.remove(id); } }