Geek asks and answers

How to highlight TextView?

What do I want to do? (blue will be changed to white) enter image description here

What I've done?
I found a class that extends TextView, capable of displaying text very close to what I want. The problem is that I could not change the color of the stroke to any color, it always paints as black. How to set border color to white?

What is my conclusion:
enter image description here

Where are my codes?

public class TypeFaceTextView extends TextView {

private static Paint getWhiteBorderPaint(){
    Paint p = new Paint(Color.WHITE);
    return p;
}

private static final Paint BLACK_BORDER_PAINT = getWhiteBorderPaint();

static {
    BLACK_BORDER_PAINT.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
}

@Override
public void setText(CharSequence text, BufferType type) {

    super.setText(String.format(text.toString()), type);
}

private static final int BORDER_WIDTH = 1;

private Typeface typeface;

public TypeFaceTextView(Context context) {
    super(context);
}

public TypeFaceTextView(Context context, AttributeSet attrs) {
    super(context, attrs);

    setDrawingCacheEnabled(false);

    setTypeface(attrs);
}

private void setTypeface(AttributeSet attrs) {
    final String typefaceFileName = attrs.getAttributeValue(null, "typeface");
    if (typefaceFileName != null) {
        typeface = Typeface.createFromAsset(getContext().getAssets(), typefaceFileName);
    }

    setTypeface(typeface);
}

public TypeFaceTextView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);

    setTypeface(attrs);
}

@Override
public void draw(Canvas aCanvas) {
    aCanvas.saveLayer(null, BLACK_BORDER_PAINT, Canvas.HAS_ALPHA_LAYER_SAVE_FLAG
            | Canvas.FULL_COLOR_LAYER_SAVE_FLAG | Canvas.MATRIX_SAVE_FLAG);

    drawBackground(aCanvas, -BORDER_WIDTH, -BORDER_WIDTH);
    drawBackground(aCanvas, BORDER_WIDTH + BORDER_WIDTH, 0);
    drawBackground(aCanvas, 0, BORDER_WIDTH + BORDER_WIDTH);
    drawBackground(aCanvas, -BORDER_WIDTH - BORDER_WIDTH, 0);

    aCanvas.restore();
    super.draw(aCanvas);

}

private void drawBackground(Canvas aCanvas, int aDX, int aDY) {
    aCanvas.translate(aDX, aDY);
    super.draw(aCanvas);
}
}
+5
source share
5 answers

1) create a textview object, extend the TextView

public class YourTextView extends TextView { .........

2) Do it by drawing method

@Override
public void draw(Canvas canvas) {
        for (int i = 0; i < 5; i++) {
        super.draw(canvas);
    }
}

3) set textview xml side below

android:shadowColor="@color/white"
android:shadowRadius="5"
+4
source

Did this fail, but try experimenting with: PorterDuff.Mode

http://developer.android.com/reference/android/graphics/PorterDuff.Mode.html

"ADD" "CLEAR", , .

0

getWhiteBorderPaint() :

private static Paint getWhiteBorderPaint(){
    Paint p = new Paint();
    p.setColor(Color.WHITE);
    return p;
}

Paint ints .

0

, . .

DST_OUT DARKEN

static {
    BLACK_BORDER_PAINT.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DARKEN));
}

-, , , .

@Override
public void draw(Canvas aCanvas) {
    int originalColor = this.getCurrentTextColor();
    this.setTextColor(0xff000000); //set it to white.

    aCanvas.saveLayer(null, borderPaint, Canvas.HAS_ALPHA_LAYER_SAVE_FLAG
            | Canvas.FULL_COLOR_LAYER_SAVE_FLAG | Canvas.MATRIX_SAVE_FLAG);

        drawBackground(aCanvas, -BORDER_WIDTH, -BORDER_WIDTH);
        drawBackground(aCanvas, BORDER_WIDTH + BORDER_WIDTH, 0);
        drawBackground(aCanvas, 0, BORDER_WIDTH + BORDER_WIDTH);
        drawBackground(aCanvas, -BORDER_WIDTH - BORDER_WIDTH, 0);

    this.setTextColor(originalColor);
    aCanvas.restore();
    super.draw(aCanvas);
}
0

I found an easy way to select a view without inheritance from a TextView . I wrote a simple library that uses Android Spannable to highlight text. This solution makes it possible to select only part of the text.

Library: OutlineSpan

Class (you can only copy a class): OutlineSpan

0
source

More articles:


All Articles