VerticalStepperItemView: Fix SDK < 21 crashes by unsupported method ObjectAnimator.ofArgb

Signed-off-by: Fung <[email protected]>

Author: fython

library/src/main/java/moe/feng/common/stepperview/VerticalStepperItemView.java

@@ -175,18 +175,17 @@ private void updateMarginBottom() {
 	 *
 	 * @param state The state of this stepper item
 	 */
-	@SuppressLint("NewApi")
 	public synchronized void setState(@State int state) {
 		// Change point background
 		if (mPointColorAnimator != null) mPointColorAnimator.cancel();
 		if (state != STATE_NORMAL && mState == STATE_NORMAL) {
-			mPointColorAnimator = ObjectAnimator
-					.ofArgb(mPointBackground, "backgroundColor", mNormalColor, mActivatedColor);
+			mPointColorAnimator = ViewUtils.createArgbAnimator(
+					mPointBackground, "backgroundColor", mNormalColor, mActivatedColor);
 			mPointColorAnimator.setDuration(mAnimationDuration);
 			mPointColorAnimator.start();
 		} else if (state == STATE_NORMAL && mState != STATE_NORMAL) {
-			mPointColorAnimator = ObjectAnimator
-					.ofArgb(mPointBackground, "backgroundColor", mActivatedColor, mNormalColor);
+			mPointColorAnimator = ViewUtils.createArgbAnimator(
+					mPointBackground, "backgroundColor", mActivatedColor, mNormalColor);
 			mPointColorAnimator.setDuration(mAnimationDuration);
 			mPointColorAnimator.start();
 		} else {
@@ -217,15 +216,13 @@ public synchronized void setState(@State int state) {
 
 		// Update error state
 		if (mErrorText != null) {
-			mTitleColorAnimator = ObjectAnimator
-					.ofArgb(mTitleText, "textColor",
-							lastTitleTextColor, mErrorColor);
+			mTitleColorAnimator = ViewUtils.createArgbAnimator(
+					mTitleText, "textColor", lastTitleTextColor, mErrorColor);
 			mTitleColorAnimator.setDuration(mAnimationDuration);
 			mTitleColorAnimator.start();
 			if (mSummaryColorAnimator != null) mSummaryColorAnimator.cancel();
-			mSummaryColorAnimator = ObjectAnimator
-					.ofArgb(mSummaryText, "textColor",
-							mSummaryText.getCurrentTextColor(), mErrorColor);
+			mSummaryColorAnimator = ViewUtils.createArgbAnimator(
+					mSummaryText, "textColor", mSummaryText.getCurrentTextColor(), mErrorColor);
 			mSummaryColorAnimator.setDuration(mAnimationDuration);
 			mSummaryColorAnimator.start();
 
@@ -242,9 +239,8 @@ public synchronized void setState(@State int state) {
 			}
 		} else {
 			if (mSummaryColorAnimator != null) mSummaryColorAnimator.cancel();
-			mSummaryColorAnimator = ObjectAnimator
-					.ofArgb(mSummaryText, "textColor",
-							mSummaryText.getCurrentTextColor(), mLineColor);
+			mSummaryColorAnimator = ViewUtils.createArgbAnimator(
+					mSummaryText, "textColor", mSummaryText.getCurrentTextColor(), mLineColor);
 			mSummaryColorAnimator.setDuration(mAnimationDuration);
 			mSummaryColorAnimator.start();
 

library/src/main/java/moe/feng/common/stepperview/ViewUtils.java

@@ -1,10 +1,14 @@
 package moe.feng.common.stepperview;
 
+import android.animation.ObjectAnimator;
+import android.animation.TypeEvaluator;
 import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.Color;
+import android.os.Build;
 import android.support.annotation.AttrRes;
 import android.support.annotation.ColorInt;
+import android.view.View;
 
 class ViewUtils {
 
@@ -23,4 +27,32 @@ static int getColorFromAttr(Context context, @AttrRes int attr) {
 		return color;
 	}
 
+	static ObjectAnimator createArgbAnimator(View view, String propertyName, int startColor, int endColor) {
+		if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
+			return ObjectAnimator.ofObject(view, propertyName, new TypeEvaluator() {
+				@Override
+				public Object evaluate(float fraction, Object startValue, Object endValue) {
+					int startInt = (Integer) startValue;
+					int startA = (startInt >> 24) & 0xff;
+					int startR = (startInt >> 16) & 0xff;
+					int startG = (startInt >> 8) & 0xff;
+					int startB = startInt & 0xff;
+
+					int endInt = (Integer) endValue;
+					int endA = (endInt >> 24) & 0xff;
+					int endR = (endInt >> 16) & 0xff;
+					int endG = (endInt >> 8) & 0xff;
+					int endB = endInt & 0xff;
+
+					return (startA + (int)(fraction * (endA - startA))) << 24 |
+							(startR + (int)(fraction * (endR - startR))) << 16 |
+							(startG + (int)(fraction * (endG - startG))) << 8 |
+							(startB + (int)(fraction * (endB - startB)));
+				}
+			}, startColor, endColor);
+		} else {
+			return ObjectAnimator.ofArgb(view, propertyName, startColor, endColor);
+		}
+	}
+
 }