Question

我正在尝试在WallpaperManager中使用ViewPager。我有一个按钮，可以将ViewPager中的当前图像设置为壁纸。我的问题来自代码行wallpManager.setResource(newInt); ...它出现的整数总是0（零），因此应用程序崩溃，LogCat说ID＃0x0没有资源。作为一个测试，看看我是否得到了正确的图像URL我已经这样做了：

String newStr = images[position];
CharSequence cs = newStr;
Toast.makeText(UILPager.this, cs, Toast.LENGTH_SHORT).show();

生成的Toast显示正确的图片网址。我无法弄清楚如何将“http://www.example.com/image.jpg”形式的URL转换为整数，以便WallpaperManager可以使用它。这是整个按钮代码的样子：

            wallp_BTN.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                WallpaperManager wallpManager = WallpaperManager.getInstance(getApplicationContext());


                String newStr = images[position];
                int newInt = 0;
                try{
                    newInt = Integer.parseInt(newStr);
                } catch(NumberFormatException nfe) {

                }

                CharSequence cs = newStr;
                try {
                    wallpManager.setResource(newInt);
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                Toast.makeText(UILPager.this, cs, Toast.LENGTH_SHORT).show();

            }

        });

Answer 1

从网址设置壁纸

    try {
        URL url = new URL("http://developer.android.com/assets/images/dac_logo.png");
        Bitmap bitmap = BitmapFactory.decodeStream(url.openStream());
        wallpaperManager.setBitmap(bitmap);
    } catch (MalformedURLException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

享受=）

Answer 2

方法wallpaperManager.setResource（）需要应用程序的资源ID。示例：我带有id＆＃34; myImage＆＃34;的ImageView然后调用该方法将看起来像wallpaperManager.setResource(R.id.myImage)。在您的情况下，您的身份证无效。

Answer 3

您应该使用wallpManager.setResource(0)代替wallpManager.setResource(R.drawable.yourimage)，因为它需要drawable而您的应用中没有{id = 0。

在您的代码中

String newStr = images[position];
int newInt = 0;
try{
    newInt = Integer.parseInt(newStr);
    } catch(NumberFormatException nfe) {

    }

由于newStr永远不是一个数字，因此始终是一个网址，因此始终会抓住NumberFormatException。因此，newInt的值始终初始化为0.因此错误。

Answer 4

我意识到在将其设置为壁纸之前我必须下载图像！感谢您的帮助AndroidWarrior和Owl。当我得到下载代码时，我会发布它。猫头鹰向我展示了如何下载壁纸：

            //--- Wallpaper button
        wallp_BTN.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                try {
                    vpURL = new URL(images[position]);
                } catch (MalformedURLException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }
                WallpaperManager wallpManager = WallpaperManager.getInstance(getApplicationContext());
                 try {
                        Bitmap bitmap = BitmapFactory.decodeStream(vpURL.openStream());
                        wallpManager.setBitmap(bitmap);
                        Toast.makeText(UILPager.this, "The wallpaper has been set!", Toast.LENGTH_LONG).show();
                    } catch (MalformedURLException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
            }

        });
        //--- END Wallpaper button

...我也想出了如何下载ViewPager图片（我需要在我的应用的不同区域同时进行）：

            //--- Wallpaper button
        wallp_BTN.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                String vpURLStr = images[position];
                GetVPImageTask downloadVPImageTask = new GetVPImageTask();
                downloadVPImageTask.execute(new String[] { vpURLStr });
            }

        });
        //--- END Wallpaper button



//--- Download ViewPager Image AsyncTask

private class GetVPImageTask extends AsyncTask<String, Void, Bitmap> {
    ProgressDialog getVPImageDia;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        getVPImageDia = new ProgressDialog(UILNPPager.this);
        getVPImageDia.setMessage("Grabbing the image...");
        getVPImageDia.setIndeterminate(false);
        getVPImageDia.show();
    }



    @Override
    protected Bitmap doInBackground(String... urls) {
        Bitmap map = null;
        for (String url : urls) {
            map = downloadImage(url);
        }
        return map;
    }

    // Sets the Bitmap returned by doInBackground
    @Override
    protected void onPostExecute(Bitmap result) {

        try {
            getVPImageDia.dismiss();
            getVPImageDia = null;
        } catch (Exception e) {
            // nothing
        }

        Toast.makeText(UILNPPager.this, "The image be Downloaded!", Toast.LENGTH_SHORT).show();
        //downloaded_iv.setImageBitmap(result);


    }

    // Creates Bitmap from InputStream and returns it
    private Bitmap downloadImage(String url) {
        Bitmap bitmap = null;
        InputStream stream = null;
        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
        bmOptions.inSampleSize = 1;

        try {
            stream = getHttpConnection(url);
            bitmap = BitmapFactory.
                    decodeStream(stream, null, bmOptions);
            stream.close();
        } catch (IOException e1) {
            e1.printStackTrace();
        }
        return bitmap;
    }

    // Makes HttpURLConnection and returns InputStream
    private InputStream getHttpConnection(String urlString)
            throws IOException {
        InputStream stream = null;
        URL url = new URL(urlString);
        URLConnection connection = url.openConnection();

        try {
            HttpURLConnection httpConnection = (HttpURLConnection) connection;
            httpConnection.setRequestMethod("GET");
            httpConnection.connect();

            if (httpConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
                stream = httpConnection.getInputStream();
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return stream;
    }
}

//--- END Download ViewPager Image AsyncTask

在Android中将字符串转换为整数

4 个答案: