Android | 通过URL获取网络图片Bitmap格式

一、获取网络图片URL

        1.随便找一张网络图片   

        2.右键打开图像

        3.复制图片URL （.jpg或者其他图像格式结尾的url才是图片的url(统一资源定位器)啊 =>=)

二、代码

        1.初始化绑定视图

    private Bitmap imgBitmap = null;
    private ImageView ivPhoto;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ivPhoto = (ImageView) findViewById(R.id.photo);
        String imgUrl = "https://w.wallhaven.cc/full/l3/wallhaven-l3xk6q.jpg";
        requestWebPhotoBitmap(imgUrl);
    }

        2.网络请求（核心代码）

                 （方法一 ：通过 HttpURLConnection 请求）

    /**
     * 通过 网络图片 url 获取图片 Bitmap
     * @param photoUrl 网络图片 url
     */
    private void requestWebPhotoBitmap(String photoUrl) {
        new Thread(() -> {
            HttpURLConnection connection = null;
            try {
                URL bitmapUrl = new URL(photoUrl);
                connection = (HttpURLConnection) bitmapUrl.openConnection();
                connection.setRequestMethod("GET");
                connection.setConnectTimeout(5000);
                connection.setReadTimeout(5000);

                // 判断是否请求成功
                if (connection.getResponseCode() == 200) {
                    Message hintMessage = new Message();
                    hintMessage.what = HANDLER_START_DOWNLOAD;
                    hintHandler.sendMessage(hintMessage);

                    InputStream inputStream = connection.getInputStream();
                    imgBitmap = BitmapFactory.decodeStream(inputStream);

                    Message message = showHandler.obtainMessage();
                    showHandler.sendMessage(message);
                } else {
                    Message hintMessage = new Message();
                    hintMessage.what = HANDLER_NET_ERROR;
                    hintHandler.sendMessage(hintMessage);
                }
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                if (connection != null) connection.disconnect();
            }
        }).start();
    }
    /**
     * 设置提示
     */
    private final Handler hintHandler = new Handler(Looper.getMainLooper()){
        @Override
        public void handleMessage(Message msg) {
            if(msg.what == HANDLER_START_DOWNLOAD)
                Toast.makeText(MainActivity.this, "获取图片中，请稍等", Toast.LENGTH_SHORT).show();
            else if(msg.what == HANDLER_NET_ERROR)
                Toast.makeText(MainActivity.this, "网络错误，请重试", Toast.LENGTH_SHORT).show();
        }
    };
    /**
     * 展示图片
     */
    @SuppressLint("HandlerLeak")
    private final Handler showHandler = new Handler(Looper.getMainLooper()) {
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            ivPhoto.setImageBitmap(imgBitmap); //填充控件
        }
    };

                （方法二 ： 通过 Glide）

    /**
     * 获取 网络图片 Bitmap
     * @param imgUrl 网络图片url
     */
    private void requestWebPhotoBitmap(String imgUrl) {
        Toast.makeText(MainActivity.this, "获取图片中，请稍等", Toast.LENGTH_SHORT).show();
        Glide.with(MainActivity.this).asBitmap().load(imgUrl).into(new CustomTarget<Bitmap>() {
            @SuppressLint("ClickableViewAccessibility")
            @Override
            public void onResourceReady(@NonNull Bitmap resource, @Nullable Transition<? super Bitmap> transition) {
                imgBitmap = resource;
                ivPhoto.setImageBitmap(imgBitmap)
            }
            @Override
            public void onLoadCleared(@Nullable Drawable placeholder) {

            }
        });
    }

        注意：使用 glide 要在 build.gradle（app）导包

    implementation 'com.github.bumptech.glide:glide:4.11.0'

        3.布局文件

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_gravity="center" >

    <ImageView
        android:id="@+id/photo"
        android:layout_width="match_parent"
        android:layout_height="500dp"
        android:layout_gravity="center"
        android:scaleType="centerInside" >
    </ImageView>

</FrameLayout>

三、效果