Provide animation when auto-scaling the font-size
Bug: 15287699
Change-Id: I5e7c5c3bdc96200efa6b4c6f221148647ff91e76
diff --git a/src/com/android/calculator2/CalculatorActivity.java b/src/com/android/calculator2/CalculatorActivity.java
index 5c47535..1600e3d 100644
--- a/src/com/android/calculator2/CalculatorActivity.java
+++ b/src/com/android/calculator2/CalculatorActivity.java
@@ -33,9 +33,13 @@
import android.view.View.OnLongClickListener;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.widget.Button;
+import android.widget.TextView;
+
+import com.android.calculator2.CalculatorEditText.OnTextSizeChangeListener;
+import com.android.calculator2.CalculatorExpressionEvaluator.EvaluateCallback;
public class CalculatorActivity extends Activity
- implements CalculatorExpressionEvaluator.EvaluateCallback, OnLongClickListener {
+ implements OnTextSizeChangeListener, EvaluateCallback, OnLongClickListener {
public static final String CALCULATOR_ACTIVITY_CURRENT_STATE =
CalculatorActivity.class.getSimpleName() + "_currentState";
@@ -89,6 +93,8 @@
mFormulaEditText.setEditableFactory(new CalculatorExpressionBuilder.Factory(this));
mFormulaEditText.addTextChangedListener(mFormulaTextWatcher);
+ mFormulaEditText.setOnTextSizeChangeListener(this);
+
mDeleteButton.setOnLongClickListener(this);
}
@@ -199,6 +205,32 @@
}
}
+ @Override
+ public void onTextSizeChanged(final TextView textView, float oldSize) {
+ if (mCurrentState != CalculatorState.INPUT) {
+ // Only animate text changes that occur from user input.
+ return;
+ }
+
+ // Calculate the values needed to perform the scale and translation animations,
+ // maintaining the same apparent baseline for the displayed text.
+ final float textScale = oldSize / textView.getTextSize();
+ final float translationX = (1.0f - textScale) *
+ (textView.getWidth() / 2.0f - textView.getPaddingEnd());
+ final float translationY = (1.0f - textScale) *
+ (textView.getHeight() / 2.0f - textView.getPaddingBottom());
+
+ final AnimatorSet animatorSet = new AnimatorSet();
+ animatorSet.playTogether(
+ ObjectAnimator.ofFloat(textView, View.SCALE_X, textScale, 1.0f),
+ ObjectAnimator.ofFloat(textView, View.SCALE_Y, textScale, 1.0f),
+ ObjectAnimator.ofFloat(textView, View.TRANSLATION_X, translationX, 0.0f),
+ ObjectAnimator.ofFloat(textView, View.TRANSLATION_Y, translationY, 0.0f));
+ animatorSet.setDuration(getResources().getInteger(android.R.integer.config_shortAnimTime));
+ animatorSet.setInterpolator(new AccelerateDecelerateInterpolator());
+ animatorSet.start();
+ }
+
private void onClear(View sourceView) {
final int[] clearLocation = new int[2];
sourceView.getLocationInWindow(clearLocation);