我想制作一个应用程序,就像 android 的打开屏幕一样。我正在将图像动态添加到 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)和图像为特定填充方面没有任何帮助。如何做到这一点?提前致谢。
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4 回答
37
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) ;
}
于 2012-06-19T12:08:26.343 回答
11
相反,您可以做的是使用 RelativeLayout 将 TextView 叠加到 ImageView :)
于 2012-06-19T12:21:27.227 回答
4
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)
}
}
于 2018-09-16T17:21:08.530 回答
3
我成功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该 EditText 和该按钮之后获取 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;
}
并单击按钮。
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);
}
享受...
于 2014-09-26T17:17:17.843 回答