prefs: Render line numbers in custom layout input box

Line numbers will help reporting errors. Also, disable line breaking to
improve readability.

srcs/juloo.keyboard2/CustomLayoutEditDialog.java

@@ -0,0 +1,90 @@
+package juloo.keyboard2;
+
+import android.app.AlertDialog;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.graphics.Canvas;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.text.InputType;
+import android.text.Layout;
+import android.widget.EditText;
+
+public class CustomLayoutEditDialog
+{
+  /** Dialog for specifying a custom layout. [initial_text] is the layout
+      description when modifying a layout. */
+  public static void show(Context ctx, String initial_text,
+      boolean allow_remove, final Callback callback)
+  {
+    final LayoutEntryEditText input = new LayoutEntryEditText(ctx);
+    input.setText(initial_text);
+    AlertDialog.Builder dialog = new AlertDialog.Builder(ctx)
+      .setView(input)
+      .setTitle(R.string.pref_custom_layout_title)
+      .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener(){
+        public void onClick(DialogInterface _dialog, int _which)
+        {
+          callback.select(input.getText().toString());
+        }
+      })
+      .setNegativeButton(android.R.string.cancel, null);
+    // Might be true when modifying an existing layout
+    if (allow_remove)
+      dialog.setNeutralButton(R.string.pref_layouts_remove_custom, new DialogInterface.OnClickListener(){
+        public void onClick(DialogInterface _dialog, int _which)
+        {
+          callback.select(null);
+        }
+      });
+    dialog.show();
+  }
+
+  public interface Callback
+  {
+    /** The entered text when the user clicks "OK", [null] when the user
+        cancels editing. */
+    public void select(String text);
+  }
+
+  /** An editable text view that shows line numbers. */
+  static class LayoutEntryEditText extends EditText
+  {
+    /** Used to draw line numbers. */
+    Paint _ln_paint;
+
+    public LayoutEntryEditText(Context ctx)
+    {
+      super(ctx);
+      _ln_paint = new Paint(getPaint());
+      _ln_paint.setTextSize(_ln_paint.getTextSize() * 0.8f);
+      setHorizontallyScrolling(true);
+      setInputType(InputType.TYPE_CLASS_TEXT
+          | InputType.TYPE_TEXT_FLAG_MULTI_LINE);
+    }
+
+    @Override
+    protected void onDraw(Canvas canvas)
+    {
+      float digit_width = _ln_paint.measureText("0");
+      int line_count = getLineCount();
+      // Extra '+ 1' serves as padding.
+      setPadding((int)(((int)Math.log10(line_count) + 1 + 1) * digit_width), 0, 0, 0);
+      super.onDraw(canvas);
+      _ln_paint.setColor(getPaint().getColor());
+      Rect clip_bounds = canvas.getClipBounds();
+      Layout layout = getLayout();
+      int offset = clip_bounds.left + (int)(digit_width / 2.f);
+      int line = layout.getLineForVertical(clip_bounds.top);
+      int skipped = line;
+      while (line < line_count)
+      {
+        int baseline = getLineBounds(line, null);
+        canvas.drawText(String.valueOf(line), offset, baseline, _ln_paint);
+        line++;
+        if (baseline >= clip_bounds.bottom)
+          break;
+      }
+    }
+  }
+}

srcs/juloo.keyboard2/LayoutsPreference.java

@@ -8,7 +8,6 @@ import android.content.res.Resources;
 import android.content.res.TypedArray;
 import android.util.AttributeSet;
 import android.widget.ArrayAdapter;
-import android.widget.EditText;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -167,27 +166,18 @@ public class LayoutsPreference extends ListGroupPreference<LayoutsPreference.Lay
       description when modifying a layout. */
   void select_custom(final SelectionCallback callback, String initial_text)
   {
-    final EditText input = new EditText(getContext());
+    boolean allow_remove = callback.allow_remove() && _values.size() > 1;
-    input.setText(initial_text);
+    CustomLayoutEditDialog.show(getContext(), initial_text, allow_remove,
-    AlertDialog.Builder dialog = new AlertDialog.Builder(getContext())
+        new CustomLayoutEditDialog.Callback()
-      .setView(input)
-      .setTitle(R.string.pref_custom_layout_title)
-      .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener(){
-        public void onClick(DialogInterface _dialog, int _which)
         {
-          callback.select(new CustomLayout(input.getText().toString()));
+          public void select(String text)
-        }
+          {
-      })
+            if (text == null)
-      .setNegativeButton(android.R.string.cancel, null);
+              callback.select(null);
-    // Might be true when modifying an existing layout
+            else
-    if (callback.allow_remove() && _values.size() > 1)
+              callback.select(new CustomLayout(text));
-      dialog.setNeutralButton(R.string.pref_layouts_remove_custom, new DialogInterface.OnClickListener(){
+          }
-        public void onClick(DialogInterface _dialog, int _which)
+        });
-        {
-          callback.select(null);
-        }
-      });
-    dialog.show();
   }
 
   /** Called when modifying a layout. Custom layouts behave differently. */