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An ImageView which supports a centered foreground drawable. - Based on Jake Wharton's ForegroundImageView
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="ForegroundImageView">
<attr name="android:foreground"/>
</declare-styleable>
</resources>
/**
* https://gist.github.com/JakeWharton/0a251d67649305d84e8a
* <p/>
* Then modified to :
* not scale the foreground to the ImageView size
* draw the foreground centered
*/
public class ForegroundImageView extends ImageView {
private Drawable foreground;
public ForegroundImageView(Context context) {
this(context, null);
}
public ForegroundImageView(Context context, AttributeSet attrs) {
super(context, attrs);
TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.ForegroundImageView);
Drawable foreground = a.getDrawable(R.styleable.ForegroundImageView_android_foreground);
if (foreground != null) {
setForeground(foreground);
}
a.recycle();
}
/**
* Supply a drawable resource that is to be rendered on top of all of the child
* views in the frame layout.
*
* @param drawableResId The drawable resource to be drawn on top of the children.
*/
public void setForegroundResource(int drawableResId) {
setForeground(getContext().getResources().getDrawable(drawableResId));
}
/**
* Supply a Drawable that is to be rendered on top of all of the child
* views in the frame layout.
*
* @param drawable The Drawable to be drawn on top of the children.
*/
public void setForeground(Drawable drawable) {
if (foreground == drawable) {
return;
}
if (foreground != null) {
foreground.setCallback(null);
unscheduleDrawable(foreground);
}
foreground = drawable;
if (drawable != null) {
drawable.setCallback(this);
if (drawable.isStateful()) {
drawable.setState(getDrawableState());
}
}
requestLayout();
invalidate();
}
@Override
protected boolean verifyDrawable(Drawable who) {
return super.verifyDrawable(who) || who == foreground;
}
@Override
public void jumpDrawablesToCurrentState() {
super.jumpDrawablesToCurrentState();
if (foreground != null) foreground.jumpToCurrentState();
}
@Override
protected void drawableStateChanged() {
super.drawableStateChanged();
if (foreground != null && foreground.isStateful()) {
foreground.setState(getDrawableState());
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (foreground != null) {
foreground.setBounds(0, 0, foreground.getIntrinsicWidth(), foreground.getIntrinsicHeight());
invalidate();
}
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
if (foreground != null) {
foreground.setBounds(0, 0, foreground.getIntrinsicWidth(), foreground.getIntrinsicHeight());
invalidate();
}
}
@Override
public void draw(Canvas canvas) {
super.draw(canvas);
if (foreground != null) {
int halfForegroundWidth = foreground.getIntrinsicWidth() / 2;
int halfForegroundHeight = foreground.getIntrinsicHeight() / 2;
int left = (getMeasuredWidth() / 2) - halfForegroundWidth;
int top = (getMeasuredHeight() / 2) - halfForegroundHeight;
canvas.save();
canvas.translate(left, top);
foreground.draw(canvas);
canvas.restore();
}
}
}
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