You are getting this.getWidth()
0 in onAttachedToWindow()
as a result the text size is set to 0.
But you are getting this.getWidth()
value in onDraw
so in onDraw
add this line
mTextPaint.setTextSize(this.getWidth() / 3);
题
I'm trying to draw text in a custom view that has an image as a background. Three things are being drawn.
At the moment the circle and bitmap draw perfectly but the text doesn't display.
Code for custom view.
public class NotificationButtonView extends Button
{
private int mNumberOfNotifications = 0;
private Paint mNotificationPaint = new Paint();
private Paint mTextPaint = new Paint();
public NotificationButtonView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public NotificationButtonView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public NotificationButtonView(Context context) {
super(context);
}
public void setNotificationNumber(int number)
{
this.mNumberOfNotifications = number;
this.invalidate();
}
public void addNotification()
{
this.mNumberOfNotifications++;
this.invalidate();
}
@Override
protected void onAttachedToWindow()
{
super.onAttachedToWindow();
mNotificationPaint.setColor(Color.rgb(255,69,0));
mNotificationPaint.setAlpha(220);
mTextPaint.setAntiAlias(true);
mTextPaint.setColor(Color.BLACK);
mTextPaint.setStyle(Style.FILL);
mTextPaint.setTextSize(this.getWidth() / 3);
mTextPaint.setTypeface(Typeface.defaultFromStyle(Typeface.BOLD));
mTextPaint.setTextAlign(Align.CENTER);
mTextPaint.setLinearText(true);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int diameter = this.getWidth() / 3;
/*
canvas.drawCircle(
this.getWidth() - diameter,
this.getHeight() - diameter,
diameter,
this.mNotificationPaint
);
*/
//Get the text bounds.
Rect foundBounds = new Rect();
mTextPaint.getTextBounds("1", 0, "1".length(), foundBounds);
foundBounds.offset(0, diameter);
canvas.drawText(
//String.valueOf(mNumberOfNotifications),
"1",
0,
foundBounds.bottom,
this.mTextPaint
);
//For testing the location of the text bounds.
canvas.drawRect(foundBounds, mNotificationPaint);
}
}
解决方案
You are getting this.getWidth()
0 in onAttachedToWindow()
as a result the text size is set to 0.
But you are getting this.getWidth()
value in onDraw
so in onDraw
add this line
mTextPaint.setTextSize(this.getWidth() / 3);