Fixed issues with selection

app/src/main/java/org/solovyev/android/calculator/Editor.java

@@ -22,6 +22,8 @@
 
 package org.solovyev.android.calculator;
 
+import static java.lang.Math.min;
+
 import android.content.SharedPreferences;
 
 import com.squareup.otto.Bus;
@@ -36,8 +38,6 @@ import javax.annotation.Nullable;
 import javax.inject.Inject;
 import javax.inject.Singleton;
 
-import static java.lang.Math.min;
-
 @Singleton
 public class Editor {
 
@@ -167,7 +167,8 @@ public class Editor {
         if (selection <= 0 || text.length() <= 0 || selection > text.length()) {
             return state;
         }
-        final String newText = text.substring(0, selection - 1) + text.substring(selection, text.length());
+        final String newText = text.substring(0, selection - 1) + text.substring(selection,
+                text.length());
         return onTextChanged(EditorState.create(newText, selection - 1));
     }
 
@@ -215,6 +216,9 @@ public class Editor {
     @Nonnull
     public EditorState setSelection(int selection) {
         Check.isMainThread();
+        if (state.selection == selection) {
+            return state;
+        }
         return onSelectionChanged(EditorState.forNewSelection(state, clamp(selection, state.text)));
     }
 

app/src/main/java/org/solovyev/android/calculator/EditorView.java

@@ -26,6 +26,8 @@ import android.annotation.TargetApi;
 import android.content.Context;
 import android.os.Build;
 import android.text.Editable;
+import android.text.Selection;
+import android.text.Spannable;
 import android.text.TextWatcher;
 import android.util.AttributeSet;
 import android.view.ContextMenu;
@@ -95,8 +97,8 @@ public class EditorView extends EditTextCompat {
         } else {
             setText(state.text, BufferType.EDITABLE);
         }
-        setSelection(Editor.clamp(state.selection, length()));
         reportChanges = true;
+        setSelection(Editor.clamp(state.selection, length()));
     }
 
     private boolean isFloatingCalculator() {
@@ -117,7 +119,6 @@ public class EditorView extends EditTextCompat {
             return;
         }
         if (editor == null) {
-            Check.shouldNotHappen();
             return;
         }
         editor.setSelection(start);

app/src/main/java/org/solovyev/android/views/Adjuster.java

@@ -5,6 +5,7 @@ import static android.graphics.Matrix.MSCALE_Y;
 import android.graphics.drawable.Drawable;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
+import android.support.v4.view.ViewCompat;
 import android.util.TypedValue;
 import android.view.View;
 import android.view.ViewTreeObserver;
@@ -52,7 +53,6 @@ public class Adjuster {
         private final TextView view;
         private final float percentage;
         private final float minTextSizePxs;
-        private int lastHeight;
 
         public TextViewAdjuster(@NonNull TextView view, float percentage, float minTextSizePxs) {
             this.view = view;
@@ -63,10 +63,13 @@ public class Adjuster {
         @Override
         public boolean onPreDraw() {
             final int height = view.getHeight();
-            if (lastHeight == height || height <= 0) {
+            if (!ViewCompat.isLaidOut(view) || height <= 0) {
                 return true;
             }
-            lastHeight = height;
+            final ViewTreeObserver treeObserver = getTreeObserver(view);
+            if (treeObserver != null) {
+                treeObserver.removeOnPreDrawListener(this);
+            }
             final float oldTextSize = Math.round(view.getTextSize());
             final float newTextSize = Math.max(minTextSizePxs, Math.round(height * percentage));
             if (oldTextSize == newTextSize) {
@@ -81,7 +84,6 @@ public class Adjuster {
         @NonNull
         private final ImageView view;
         private final float percentage;
-        private int lastHeight;
 
         public ImageViewAdjuster(@NonNull ImageView view, float percentage) {
             this.view = view;
@@ -91,10 +93,13 @@ public class Adjuster {
         @Override
         public boolean onPreDraw() {
             final int height = view.getHeight();
-            if (lastHeight == height || height <= 0) {
+            if (!ViewCompat.isLaidOut(view) || height <= 0) {
                 return true;
             }
-            lastHeight = height;
+            final ViewTreeObserver treeObserver = getTreeObserver(view);
+            if (treeObserver != null) {
+                treeObserver.removeOnPreDrawListener(this);
+            }
             final Drawable d = view.getDrawable();
             if (d == null) {
                 return true;