Add CircleButtonText (same as CircleButton but extends TextView)

README.md

@@ -39,3 +39,15 @@ Example Usage:
 
 </FrameLayout>
 ```
+
+You can use text for the button's content too.
+```
+<at.markushi.ui.CircleButtonText
+        android:layout_width="64dip"
+        android:layout_height="64dip"
+        android:text="A"
+        android:textSize="25sp"
+        android:textColor="#000000"
+        app:cb_color="#99CC00"
+        app:cb_pressedRingWidth="8dip" />
+```

library/src/main/java/at/markushi/ui/CircleButtonText.java

@@ -0,0 +1,148 @@
+package at.markushi.ui;
+
+import android.animation.ObjectAnimator;
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.util.AttributeSet;
+import android.util.TypedValue;
+import android.view.Gravity;
+import android.widget.TextView;
+
+import at.markushi.circlebutton.R;
+
+public class CircleButtonText extends TextView {
+
+    private static final int PRESSED_COLOR_LIGHTUP = 255 / 25;
+    private static final int PRESSED_RING_ALPHA = 75;
+    private static final int DEFAULT_PRESSED_RING_WIDTH_DIP = 4;
+    private static final int ANIMATION_TIME_ID = android.R.integer.config_shortAnimTime;
+
+    private int centerY;
+    private int centerX;
+    private int outerRadius;
+    private int pressedRingRadius;
+
+    private Paint circlePaint;
+    private Paint focusPaint;
+
+    private float animationProgress;
+
+    private int pressedRingWidth;
+    private int defaultColor = Color.BLACK;
+    private int pressedColor;
+    private ObjectAnimator pressedAnimator;
+
+    public CircleButtonText(Context context) {
+        super(context);
+        init(context, null);
+    }
+
+    public CircleButtonText(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        init(context, attrs);
+    }
+
+    public CircleButtonText(Context context, AttributeSet attrs, int defStyle) {
+        super(context, attrs, defStyle);
+        init(context, attrs);
+    }
+
+    @Override
+    public void setPressed(boolean pressed) {
+        super.setPressed(pressed);
+
+        if (circlePaint != null) {
+            circlePaint.setColor(pressed ? pressedColor : defaultColor);
+        }
+
+        if (pressed) {
+            showPressedRing();
+        } else {
+            hidePressedRing();
+        }
+    }
+
+    @Override
+    protected void onDraw(Canvas canvas) {
+        canvas.drawCircle(centerX, centerY, pressedRingRadius + animationProgress, focusPaint);
+        canvas.drawCircle(centerX, centerY, outerRadius - pressedRingWidth, circlePaint);
+        super.onDraw(canvas);
+    }
+
+    @Override
+    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
+        super.onSizeChanged(w, h, oldw, oldh);
+        centerX = w / 2;
+        centerY = h / 2;
+        outerRadius = Math.min(w, h) / 2;
+        pressedRingRadius = outerRadius - pressedRingWidth - pressedRingWidth / 2;
+    }
+
+    public float getAnimationProgress() {
+        return animationProgress;
+    }
+
+    public void setAnimationProgress(float animationProgress) {
+        this.animationProgress = animationProgress;
+        this.invalidate();
+    }
+
+    public void setColor(int color) {
+        this.defaultColor = color;
+        this.pressedColor = getHighlightColor(color, PRESSED_COLOR_LIGHTUP);
+
+        circlePaint.setColor(defaultColor);
+        focusPaint.setColor(defaultColor);
+        focusPaint.setAlpha(PRESSED_RING_ALPHA);
+
+        this.invalidate();
+    }
+
+    private void hidePressedRing() {
+        pressedAnimator.setFloatValues(pressedRingWidth, 0f);
+        pressedAnimator.start();
+    }
+
+    private void showPressedRing() {
+        pressedAnimator.setFloatValues(animationProgress, pressedRingWidth);
+        pressedAnimator.start();
+    }
+
+    private void init(Context context, AttributeSet attrs) {
+        this.setFocusable(true);
+        this.setGravity(Gravity.CENTER);
+        setClickable(true);
+
+        circlePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
+        circlePaint.setStyle(Paint.Style.FILL);
+
+        focusPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
+        focusPaint.setStyle(Paint.Style.STROKE);
+
+        pressedRingWidth = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, DEFAULT_PRESSED_RING_WIDTH_DIP, getResources()
+                .getDisplayMetrics());
+
+        int color = Color.BLACK;
+        if (attrs != null) {
+            final TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleButton);
+            color = a.getColor(R.styleable.CircleButton_cb_color, color);
+            pressedRingWidth = (int) a.getDimension(R.styleable.CircleButton_cb_pressedRingWidth, pressedRingWidth);
+            a.recycle();
+        }
+
+        setColor(color);
+
+        focusPaint.setStrokeWidth(pressedRingWidth);
+        final int pressedAnimationTime = getResources().getInteger(ANIMATION_TIME_ID);
+        pressedAnimator = ObjectAnimator.ofFloat(this, "animationProgress", 0f, 0f);
+        pressedAnimator.setDuration(pressedAnimationTime);
+    }
+
+    private int getHighlightColor(int color, int amount) {
+        return Color.argb(Math.min(255, Color.alpha(color)), Math.min(255, Color.red(color) + amount),
+                Math.min(255, Color.green(color) + amount), Math.min(255, Color.blue(color) + amount));
+    }
+}