以编程方式在android中向图像添加文本

Add text to image in android programmatically

提问by dka72

I want to make an application just like opening screen of android.I am dynamically adding images to the rows of tableLayout. I have only defined tableLayout in xml file and remaining code is in java. I have added images successfully but i am not getting any help with setting text of that image (I want to display a text under image) and image to be a specific padding.How to do it?Thanks in advance.

我想做一个应用程序，就像android的打开屏幕一样。我正在动态地将图像添加到tableLayout的行中。我只在 xml 文件中定义了 tableLayout，其余代码在 java 中。我已成功添加图像，但在设置该图像的文本（我想在图像下显示文本）和图像作为特定填充时，我没有得到任何帮助。如何做？提前致谢。

采纳答案by StErMi

What you can instead do is to put a TextView in overlay to a ImageView using a RelativeLayout :)

您可以做的是使用 RelativeLayout 将 TextView 叠加到 ImageView 中:)

回答by Arun George

Use the following function to write Text on Images:

使用以下函数在图像上写入文本：

private BitmapDrawable writeTextOnDrawable(int drawableId, String text) {

    Bitmap bm = BitmapFactory.decodeResource(getResources(), drawableId)
            .copy(Bitmap.Config.ARGB_8888, true);

    Typeface tf = Typeface.create("Helvetica", Typeface.BOLD);

    Paint paint = new Paint();
    paint.setStyle(Style.FILL);
    paint.setColor(Color.WHITE);
    paint.setTypeface(tf);
    paint.setTextAlign(Align.CENTER);
    paint.setTextSize(convertToPixels(mContext, 11));

    Rect textRect = new Rect();
    paint.getTextBounds(text, 0, text.length(), textRect);

    Canvas canvas = new Canvas(bm);

    //If the text is bigger than the canvas , reduce the font size
    if(textRect.width() >= (canvas.getWidth() - 4))     //the padding on either sides is considered as 4, so as to appropriately fit in the text
        paint.setTextSize(convertToPixels(mContext, 7));        //Scaling needs to be used for different dpi's

    //Calculate the positions
    int xPos = (canvas.getWidth() / 2) - 2;     //-2 is for regulating the x position offset

    //"- ((paint.descent() + paint.ascent()) / 2)" is the distance from the baseline to the center.
    int yPos = (int) ((canvas.getHeight() / 2) - ((paint.descent() + paint.ascent()) / 2)) ;  

    canvas.drawText(text, xPos, yPos, paint);

    return new BitmapDrawable(getResources(), bm);
}



public static int convertToPixels(Context context, int nDP)
{
    final float conversionScale = context.getResources().getDisplayMetrics().density;

    return (int) ((nDP * conversionScale) + 0.5f) ;

}

回答by kosiara - Bartosz Kosarzycki

Here's Kotlin version Arun's solution:

这是 Kotlin 版本 Arun 的解决方案：

import org.jetbrains.anko.dip

fun Context.writeTextOnDrawable(drawableId: Int, text: String) =
        DrawableUtil.writeTextOnDrawableInternal(this, drawableId, text, 25, -2, 0)

object DrawableUtil {

    fun writeTextOnDrawableInternal(context: Context, drawableId: Int, text: String,
            textSizeDp: Int, horizontalOffset: Int, verticalOffset: Int): BitmapDrawable {

        val bm = BitmapFactory.decodeResource(context.resources, drawableId)
                .copy(Bitmap.Config.ARGB_8888, true)

        val tf = Typeface.create("Helvetica", Typeface.BOLD)

        val paint = Paint()
        paint.style = Paint.Style.FILL
        paint.color = Color.WHITE
        paint.typeface = tf
        paint.textAlign = Paint.Align.LEFT
        paint.textSize = context.dip(textSizeDp).toFloat()

        val textRect = Rect()
        paint.getTextBounds(text, 0, text.length, textRect)

        val canvas = Canvas(bm)

        //If the text is bigger than the canvas , reduce the font size
        if (textRect.width() >= canvas.getWidth() - 4)
            //the padding on either sides is considered as 4, so as to appropriately fit in the text
            paint.textSize = context.dip(12).toFloat()

        //Calculate the positions
        val xPos = canvas.width.toFloat()/2 + horizontalOffset  

        //"- ((paint.descent() + paint.ascent()) / 2)" is the distance from the baseline to the center.
        val yPos = (canvas.height / 2 - (paint.descent() + paint.ascent()) / 2) + verticalOffset

        canvas.drawText(text, xPos, yPos, paint)

        return BitmapDrawable(context.resources, bm)
    }
}

回答by Ganesh Katikar

I m successfully implemented such problem of adding text on image. Just look at following code. First of take one view as Relative layout in that layout take ImageView after that EditText and after that button. Give each of a id. Write a loadBitmapFromView function below.

我成功地实现了在图像上添加文本的问题。看看下面的代码。首先将一个视图作为该布局中的相对布局，在那个 EditText 和那个按钮之后取 ImageView。给每个人一个id。下面写一个 loadBitmapFromView 函数。

public Bitmap loadBitmapFromView(View v) {
        Bitmap b = Bitmap.createBitmap(v.getWidth(), v.getHeight(), Config.ARGB_8888);
        Canvas c = new Canvas(b);
        v.layout(v.getLeft(), v.getTop(), v.getRight(), v.getBottom());
        v.draw(c);
        return b;
    }

and on click of button.

并点击按钮。

               Bitmap bitmap = loadBitmapFromView(relativeLayout);
                File dir = new File(Environment.getExternalStorageDirectory().getAbsolutePath(),         "folderName");
                if (!dir.exists())
                    dir.mkdirs();

                File file = new File(dir, "capture.jpg");
                try {
                    FileOutputStream fos = new FileOutputStream(file);
                    bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
                    imageView.setImageBitmap(bitmap);    
                } catch (Exception e) {
                    Log.e("ExpressionEditImageActivity", "Error, " + e);
                }

Enjoy...

享受...

For more reference, refer below screenshot:

如需更多参考，请参阅以下屏幕截图：