Utils.java revision ad31f63f5843898de645f6ee1ac244c872ded8cc 
1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5 * in compliance with the License. You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software distributed under the License
10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11 * or implied. See the License for the specific language governing permissions and limitations under
12 * the License.
13 */
14
15package android.support.v17.leanback.supportleanbackshowcase.utils;
16
17import android.content.ContentResolver;
18import android.content.Context;
19import android.graphics.drawable.Drawable;
20import android.net.Uri;
21import android.widget.ImageView;
22
23import com.squareup.picasso.Picasso;
24import com.squareup.picasso.RequestCreator;
25
26import java.io.IOException;
27import java.io.InputStream;
28import java.net.URI;
29
30/**
31 * A collection of utility methods, all static.
32 */
33public class Utils {
34
35    public static int convertDpToPixel(Context ctx, int dp) {
36        float density = ctx.getResources().getDisplayMetrics().density;
37        return Math.round((float) dp * density);
38    }
39
40    /**
41     * Will read the content from a given {@link InputStream} and return it as a {@link String}.
42     *
43     * @param inputStream The {@link InputStream} which should be read.
44     * @return Returns <code>null</code> if the the {@link InputStream} could not be read. Else
45     * returns the content of the {@link InputStream} as {@link String}.
46     */
47    public static String inputStreamToString(InputStream inputStream) {
48        try {
49            byte[] bytes = new byte[inputStream.available()];
50            inputStream.read(bytes, 0, bytes.length);
51            String json = new String(bytes);
52            return json;
53        } catch (IOException e) {
54            return null;
55        }
56    }
57
58    /**
59     * The method uses {@link Picasso} to fetch an image from a given url, resize it (if required)
60     * and display it inside an {@link ImageView}.
61     *
62     * @param context Context which is used to create a {@link Picasso} instance.
63     * @param uri The {@link URI} to fetch the image from.
64     * @param target The {@link ImageView} which shall display the image.
65     * @param resizeWidthInDp The target width of the image. Pass <code>-1</code> if you don't want
66     * to resize the image.
67     * @param resizeHeightInDp The target height of the image. Pass <code>-1</code> if you don't
68     * want to resize the image.
69     * @param centerCrop Centers and scales an image to fit the requested bounds.
70     * @param errorDrawable A drawable which will be shown in case the image could not be fetched
71     * from the server.
72     * @see {@link Picasso#with(Context)}
73     * @see {@link RequestCreator#resize(int, int)}
74     * @see {@link RequestCreator#centerCrop()}
75     * @see {@link RequestCreator#error(Drawable)}
76     */
77    public static void loadImageFromUri(Context context, URI uri, ImageView target,
78                                        int resizeWidthInDp, int resizeHeightInDp,
79                                        boolean centerCrop, Drawable errorDrawable) {
80        if (uri == null) return;
81        RequestCreator builder = Picasso.with(context).load(uri.toString());
82        if (resizeHeightInDp != -1 && resizeWidthInDp != -1)
83            builder.resize(Utils.convertDpToPixel(context, resizeWidthInDp),
84                           Utils.convertDpToPixel(context, resizeHeightInDp));
85        if (centerCrop) builder.centerCrop();
86        builder.error(errorDrawable).into(target);
87    }
88
89    public static Uri getResourceUri(Context context, int resID) {
90        return Uri.parse(ContentResolver.SCHEME_ANDROID_RESOURCE + "://" +
91                                 context.getResources().getResourcePackageName(resID) + '/' +
92                                 context.getResources().getResourceTypeName(resID) + '/' +
93                                 context.getResources().getResourceEntryName(resID));
94    }
95}
96