Improve line number drawing performance

Author: AmrDeveloper

codeview/src/main/java/com/amrdeveloper/codeview/CodeView.java

@@ -132,22 +132,25 @@ private void initEditorView() {
 
     @Override
     protected void onDraw(Canvas canvas) {
-        if (enableLineNumber) {
-            int baseline;
-            int lineCount = getLineCount();
-            int lineNumber = 1;
-
-            for (int i = 0; i < lineCount; ++i) {
-                baseline = getLineBounds(i, null);
-                if (i == 0 || getText().charAt(getLayout().getLineStart(i) - 1) == '\n') {
-                    canvas.drawText(String.format(Locale.ENGLISH, " %d", lineNumber), lineNumberRect.left, baseline, lineNumberPaint);
-                    ++lineNumber;
-                }
+        if (!enableLineNumber) return;
+
+        final Editable fullText = getText();
+        final Layout layout = getLayout();
+        final int lineCount = getLineCount();
+        int baseline;
+        int currentLineNumber = 1;
+
+        for (int i = 0; i < lineCount; ++i) {
+            baseline = getLineBounds(i, null);
+            if (i == 0 || fullText.charAt(layout.getLineStart(i) - 1) == '\n') {
+                canvas.drawText(" " + currentLineNumber, lineNumberRect.left, baseline, lineNumberPaint);
+                ++currentLineNumber;
             }
-
-            int paddingLeft = 40 + (int) (Math.log10(lineCount) + 1) * 10;
-            setPadding(paddingLeft, getPaddingTop(), getPaddingRight(), getPaddingBottom());
         }
+
+        int paddingLeft = 40 + (int) (Math.log10(lineCount) + 1) * 10;
+        setPadding(paddingLeft, getPaddingTop(), getPaddingRight(), getPaddingBottom());
+
         super.onDraw(canvas);
     }