可以在不显示相对视图的情况下加载相对视图吗

Question

我正在尝试用文本保存图像。为了做到这一点，我使用了位图和画布，但保存的图像不清楚，所以我正在尝试这个解决方案

如何将具有Imageview和TextView的RelativeLayout转换为PNG图像？

现在这个东西工作得很好，图像质量也很好，但有一个问题

 RelativeLayout relativeLayout = (RelativeLayout)findViewById(R.id.relativeLayout);
    TextView textView = (TextView)relativeLayout.findViewById(R.id.quote);
     textView.setText("My custom Text adding to Image hare ram");
    Bitmap bitmap = Bitmap.createBitmap(relativeLayout.getWidth(), relativeLayout.getHeight(), Bitmap.Config.ARGB_8888);
    Canvas c = new Canvas(bitmap);
    relativeLayout.draw(c);
    new SaveToGalary(bitmap)

但现在，如果我试图编辑这个相对布局，它会反映在屏幕上，有什么办法可以让我复制一下这个视图吗或我可以加载一个当前未显示的布局吗。例如，我将进行

RelativeLayout relativeLayout = (RelativeLayout)findViewById(R.id.to_save_layout);
    TextView textView = (TextView)relativeLayout.findViewById(R.id.quote);
     textView.setText("My custom Text adding to Image hare ram");
    Bitmap bitmap = Bitmap.createBitmap(relativeLayout.getWidth(), relativeLayout.getHeight(), Bitmap.Config.ARGB_8888);
    Canvas c = new Canvas(bitmap);
    relativeLayout.draw(c);
    new SaveToGalary(bitmap)

在这里，我将创建一个布局，我不会显示，只是保留它来保存图像。我试过了，但这给了我空指针异常。

Answer 1

Mike给出了一个完美的答案，总结起来我们可以做

public void GenerateImageRelative()
{
    LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View view = inflater.inflate(R.layout.to_save_image, null);
    RelativeLayout relativeLayout = (RelativeLayout)view.findViewById(R.id.to_save_image_relative);
    Bitmap bitmap = getLayoutRender(view, -1, -1);
    Canvas c = new Canvas(bitmap);
    relativeLayout.draw(c);
    new SaveToGalary().insertImage(getContentResolver(),bitmap,"man","ram");
}
private Bitmap getLayoutRender(View rootView, int width, int height) {
    TextView textView = (TextView)rootView.findViewById(R.id.quote_to_save);
    textView.setText("My custom Text adding to Image hare ram");
    // Here you can call findViewById() on rootView just like usual
    // to get references to Views you want to change.
    Display display = getWindowManager().getDefaultDisplay();
    int w,h;
    if (android.os.Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB_MR2) {
         w =  width < 0 ? display.getWidth():width;
         h =  height < 0 ? display.getHeight() : height;
    } else {
        Point size = new Point();
        display.getSize(size);
         w = width < 0 ?size.x: width;
         h =  height < 0 ?size.y:height;
    }
    rootView.measure(View.MeasureSpec.makeMeasureSpec(w, View.MeasureSpec.EXACTLY),
            View.MeasureSpec.makeMeasureSpec(h, View.MeasureSpec.EXACTLY));
    rootView.layout(0, 0, rootView.getMeasuredWidth(), rootView.getMeasuredHeight());
    rootView.setDrawingCacheEnabled(true);
    rootView.buildDrawingCache();
    Bitmap bmp = rootView.getDrawingCache();
    return bmp;
}

以及用于将图像保存到库

import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.graphics.Bitmap;
import android.graphics.Matrix;
import android.net.Uri;
import android.provider.MediaStore;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;

public class SaveToGalary {
public static final String insertImage(ContentResolver cr, Bitmap source, String title, String description) {
    ContentValues values = new ContentValues();
    values.put(MediaStore.Images.Media.TITLE, title);
    values.put(MediaStore.Images.Media.DISPLAY_NAME, title);
    values.put(MediaStore.Images.Media.DESCRIPTION, description);
    values.put(MediaStore.Images.Media.MIME_TYPE, "image/png");
    // Add the date meta data to ensure the image is added at the front of the gallery
    values.put(MediaStore.Images.Media.DATE_ADDED, System.currentTimeMillis());
    values.put(MediaStore.Images.Media.DATE_TAKEN, System.currentTimeMillis());
    Uri url = null;
    String stringUrl = null;    /* value to be returned */
    try {
        url = cr.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
        if (source != null) {
            OutputStream imageOut = cr.openOutputStream(url);
            try {
                source.compress(Bitmap.CompressFormat.PNG, 100, imageOut);
            } finally {
                imageOut.close();
            }
            long id = ContentUris.parseId(url);
            // Wait until MINI_KIND thumbnail is generated.
            Bitmap miniThumb = MediaStore.Images.Thumbnails.getThumbnail(cr, id, MediaStore.Images.Thumbnails.MINI_KIND, null);
            // This is for backward compatibility.
            storeThumbnail(cr, miniThumb, id, 50F, 50F, MediaStore.Images.Thumbnails.MICRO_KIND);
        } else {
            cr.delete(url, null, null);
            url = null;
        }
    } catch (Exception e) {
        if (url != null) {
            cr.delete(url, null, null);
            url = null;
        }
    }
    if (url != null) {
        stringUrl = url.toString();
    }
    return stringUrl;
}
/**
 * A copy of the Android internals StoreThumbnail method, it used with the insertImage to
 * populate the android.provider.MediaStore.Images.Media#insertImage with all the correct
 * meta data. The StoreThumbnail method is private so it must be duplicated here.
 * @see android.provider.MediaStore.Images.Media (StoreThumbnail private method)
 */
private static final Bitmap storeThumbnail(
        ContentResolver cr,
        Bitmap source,
        long id,
        float width,
        float height,
        int kind) throws FileNotFoundException {
    // create the matrix to scale it
    Matrix matrix = new Matrix();
    float scaleX = width / source.getWidth();
    float scaleY = height / source.getHeight();
    matrix.setScale(scaleX, scaleY);
    Bitmap thumb = Bitmap.createBitmap(source, 0, 0,
            source.getWidth(),
            source.getHeight(), matrix,
            true
    );
    ContentValues values = new ContentValues(4);
    values.put(MediaStore.Images.Thumbnails.KIND,kind);
    values.put(MediaStore.Images.Thumbnails.IMAGE_ID,(int)id);
    values.put(MediaStore.Images.Thumbnails.HEIGHT,thumb.getHeight());
    values.put(MediaStore.Images.Thumbnails.WIDTH,thumb.getWidth());
    Uri url = cr.insert(MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, values);
    try {
        OutputStream thumbOut = cr.openOutputStream(url);
        thumb.compress(Bitmap.CompressFormat.JPEG, 100, thumbOut);
        thumbOut.close();
        return thumb;
    } catch (FileNotFoundException ex) {
        return null;
    } catch (IOException ex) {
        return null;
    }
}

}