Don't trigger TextView relayouts if content doesn't change

We have a few views we commonly update in response to updates - clock, battery and similar percentages. These updates always trigger a requestLayout() call because wrap_content TextViews do that on every setText() call. This CL adds a few guards to lower the amount of relayouts when the content didn't actually update.

Bug:228203088
Bug:228166250

Test: On a physical deviceo
Change-Id: I6b92f8bfb7aea17e93ff0cbb8507a995f6323ca1

packages/SystemUI/src/com/android/keyguard/AnimatableClockView.kt

@@ -22,6 +22,7 @@ import android.annotation.IntRange
 import android.annotation.SuppressLint
 import android.content.Context
 import android.graphics.Canvas
+import android.text.TextUtils
 import android.text.format.DateFormat
 import android.util.AttributeSet
 import android.util.Log
@@ -125,13 +126,30 @@ class AnimatableClockView @JvmOverloads constructor(
 
     fun refreshTime() {
         time.timeInMillis = System.currentTimeMillis()
-        text = DateFormat.format(format, time)
         contentDescription = DateFormat.format(descFormat, time)
-        Log.d(tag, "refreshTime this=$this" +
-                " currTimeContextDesc=$contentDescription" +
-                " measuredHeight=$measuredHeight" +
-                " lastMeasureCall=$lastMeasureCall" +
-                " isSingleLineInternal=$isSingleLineInternal")
+        val formattedText = DateFormat.format(format, time)
+        // Setting text actually triggers a layout pass (because the text view is set to
+        // wrap_content width and TextView always relayouts for this). Avoid needless
+        // relayout if the text didn't actually change.
+        if (!TextUtils.equals(text, formattedText)) {
+            text = formattedText
+            Log.d(
+                tag, "refreshTime this=$this" +
+                        " currTimeContextDesc=$contentDescription" +
+                        " measuredHeight=$measuredHeight" +
+                        " lastMeasureCall=$lastMeasureCall" +
+                        " isSingleLineInternal=$isSingleLineInternal"
+            )
+        } else {
+            Log.d(
+                tag, "refreshTime (skipped due to unchanged text)" +
+                        " this=$this" +
+                        " currTimeContextDesc=$contentDescription" +
+                        " measuredHeight=$measuredHeight" +
+                        " lastMeasureCall=$lastMeasureCall" +
+                        " isSingleLineInternal=$isSingleLineInternal"
+            )
+        }
     }
 
     fun onTimeZoneChanged(timeZone: TimeZone?) {

packages/SystemUI/src/com/android/systemui/battery/BatteryMeterView.java

@@ -32,6 +32,7 @@ import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.os.UserHandle;
 import android.provider.Settings;
+import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.util.TypedValue;
 import android.view.Gravity;
@@ -267,8 +268,15 @@ public class BatteryMeterView extends LinearLayout implements DarkReceiver {
         if (mBatteryPercentView == null) {
             return;
         }
-        mBatteryPercentView.setText(
-                NumberFormat.getPercentInstance().format(mLevel / 100f));
+
+        String percentText = NumberFormat.getPercentInstance().format(mLevel / 100f);
+        // Setting text actually triggers a layout pass (because the text view is set to
+        // wrap_content width and TextView always relayouts for this). Avoid needless
+        // relayout if the text didn't actually change.
+        if (!TextUtils.equals(mBatteryPercentView.getText(), percentText)) {
+            mBatteryPercentView.setText(percentText);
+        }
+
         setContentDescription(
                 getContext().getString(mCharging ? R.string.accessibility_battery_level_charging
                         : R.string.accessibility_battery_level, mLevel));

packages/SystemUI/src/com/android/systemui/statusbar/policy/Clock.java

@@ -31,6 +31,7 @@ import android.os.SystemClock;
 import android.os.UserHandle;
 import android.text.Spannable;
 import android.text.SpannableStringBuilder;
+import android.text.TextUtils;
 import android.text.format.DateFormat;
 import android.text.style.CharacterStyle;
 import android.text.style.RelativeSizeSpan;
@@ -291,7 +292,13 @@ public class Clock extends TextView implements
     final void updateClock() {
         if (mDemoMode) return;
         mCalendar.setTimeInMillis(System.currentTimeMillis());
-        setText(getSmallTime());
+        CharSequence smallTime = getSmallTime();
+        // Setting text actually triggers a layout pass (because the text view is set to
+        // wrap_content width and TextView always relayouts for this). Avoid needless
+        // relayout if the text didn't actually change.
+        if (!TextUtils.equals(smallTime, getText())) {
+            setText(smallTime);
+        }
         setContentDescription(mContentDescriptionFormat.format(mCalendar.getTime()));
     }