fix linear layout implementation

examples/example1/winmain.d

@@ -27,9 +27,20 @@ extern (C) int UIAppMain(string[] args) {
 
     // create window
     Window window = Platform.instance().createWindow("My Window", null);
-    Widget myWidget = (new Button()).textColor(0x40FF4000);
+	LinearLayout layout = new LinearLayout();
-    myWidget.text = "Some strange text string. 1234567890";
+	layout.addChild((new TextWidget()).textColor(0x00802000).text("Text widget 0"));
-    window.mainWidget = myWidget;
+	layout.addChild((new TextWidget()).textColor(0x40FF4000).text("Text widget"));
+	layout.addChild((new Button()).textColor(0x40FF4000).text("Button1"));
+	layout.addChild((new Button()).textColor(0x000000FF).text("Button2"));
+	layout.addChild((new TextWidget()).textColor(0x40FF4000).text("Text widget"));
+	layout.addChild((new ImageWidget()).drawableId("exit").padding(Rect(5,5,5,5)));
+	layout.addChild((new TextWidget()).textColor(0xFF4000).text("Text widget2").padding(Rect(5,5,5,5)).margins(Rect(5,5,5,5)).backgroundColor(0xA0A0A0));
+	layout.addChild((new Button()).textColor(0x000000FF).text("Button3").layoutHeight(FILL_PARENT));
+	layout.addChild((new TextWidget()).textColor(0x004000).text("Text widget3 with very long text"));
+
+	layout.layoutHeight(FILL_PARENT).layoutWidth(FILL_PARENT);
+
+    window.mainWidget = layout;
     window.show();
     window.windowCaption = "New Window Caption";
 

src/dlangui/all.d

@@ -1,8 +1,10 @@
 module dlangui.all;
 
+public import dlangui.core.logger;
+public import dlangui.core.types;
 public import dlangui.platforms.common.platform;
 public import dlangui.graphics.images;
 public import dlangui.widgets.widget;
 public import dlangui.widgets.controls;
-public import dlangui.core.logger;
+public import dlangui.widgets.layouts;
 public import dlangui.graphics.fonts;

src/dlangui/widgets/controls.d

@@ -4,16 +4,20 @@ import dlangui.widgets.widget;
 
 /// static text widget
 class TextWidget : Widget {
+    this(string ID = null) {
+		super(ID);
+        styleId = "TEXT";
+    }
     protected dstring _text;
     /// get widget text
     override @property dstring text() { return _text; }
     /// set text to show
-    override @property void text(dstring s) { 
+    override @property Widget text(dstring s) { 
         _text = s; 
         requestLayout();
+		return this;
     }
     override void measure(int parentWidth, int parentHeight) { 
-        _measuredWidth = _measuredHeight = 0;
         FontRef font = font();
         Point sz = font.textSize(text);
         measuredContent(parentWidth, parentHeight, sz.x, sz.y);
@@ -24,8 +28,8 @@ class TextWidget : Widget {
         super.onDraw(buf);
         Rect rc = _pos;
         applyMargins(rc);
-        applyPadding(rc);
         ClipRectSaver(buf, rc);
+        applyPadding(rc);
         FontRef font = font();
         Point sz = font.textSize(text);
         applyAlign(rc, sz);
@@ -39,6 +43,10 @@ class ImageWidget : Widget {
     protected string _drawableId;
     protected DrawableRef _drawable;
 
+    this(string ID = null) {
+		super(ID);
+	}
+
     /// get drawable image id
     @property string drawableId() { return _drawableId; }
     /// set drawable image id
@@ -79,8 +87,8 @@ class ImageWidget : Widget {
         super.onDraw(buf);
         Rect rc = _pos;
         applyMargins(rc);
-        applyPadding(rc);
         ClipRectSaver(buf, rc);
+        applyPadding(rc);
         DrawableRef img = drawable;
         if (!img.isNull) {
             Point sz;
@@ -95,16 +103,15 @@ class ImageWidget : Widget {
 class Button : Widget {
     protected dstring _text;
     override @property dstring text() { return _text; }
-    override @property void text(dstring s) { _text = s; }
+    override @property Widget text(dstring s) { _text = s; requestLayout(); return this; }
-    this() {
+    this(string ID = null) {
+		super(ID);
         styleId = "BUTTON";
     }
-    override void measure(int width, int height) { 
+    override void measure(int parentWidth, int parentHeight) { 
-        _measuredWidth = _measuredHeight = 0;
+        FontRef font = font();
-    }
+        Point sz = font.textSize(text);
-    override void layout(Rect rc) { 
+        measuredContent(parentWidth, parentHeight, sz.x, sz.y);
-        _pos = rc;
-        _needLayout = false;
     }
     override void onDraw(DrawBuf buf) {
         super.onDraw(buf);

src/dlangui/widgets/layouts.d

@@ -74,7 +74,6 @@ class LinearLayout : WidgetGroup {
         int contentHeight = 0;
         if (orientation == Orientation.Vertical) {
             // Vertical
-            int position = 0;
             int totalSize = 0;
             int delta = 0;
             int resizableSize = 0;
@@ -89,16 +88,17 @@ class LinearLayout : WidgetGroup {
                 if (item.visibility == Visibility.Gone)
                     continue;
                 visibleCount++;
-                totalSize += item.measuredHeight;
+                int weight = item.layoutWeight;
+				int size = item.measuredHeight;
+                totalSize += size;
                 if (maxItem < item.measuredWidth)
                     maxItem = item.measuredWidth;
-                int weight = item.layoutWeight;
                 if (item.layoutHeight == FILL_PARENT) {
                     resizableWeight += weight;
-                    resizableSize += item.measuredHeight;
+                    resizableSize += size * weight;
                 } else {
                     nonresizableWeight += weight;
-                    nonresizableSize += item.measuredHeight;
+                    nonresizableSize += size * weight;
                 }
             }
             if (layoutWidth == WRAP_CONTENT && maxItem < rc.width)
@@ -107,42 +107,59 @@ class LinearLayout : WidgetGroup {
                 contentWidth = rc.width;
             if (layoutHeight == FILL_PARENT || totalSize > rc.height)
                 delta = rc.height - totalSize; // total space to add to fit
+			// calculate resize options and scale
             bool needForceResize = false;
             bool needResize = false;
             int scaleFactor = 10000; // per weight unit
             if (delta != 0 && visibleCount > 0) {
                 // need resize of some children
                 needResize = true;
-                needForceResize = delta < 0 || resizableSize < delta; // do we need resize non-FILL_PARENT items?
+				// resize all if need to shrink or only resizable are too small to correct delta
+                needForceResize = delta < 0 || resizableWeight == 0; // || resizableSize * 2 / 3 < delta; // do we need resize non-FILL_PARENT items?
+				// calculate scale factor: weight / delta * 10000
                 if (needForceResize)
-                    scaleFactor = 10000 * rc.height / (resizableSize + nonresizableSize) / (nonresizableWeight + resizableWeight);
+                    scaleFactor = 10000 * delta / (nonresizableSize + resizableSize);
                 else
-                    scaleFactor = 10000 * rc.height / (rc.height - delta) / resizableWeight;
+                    scaleFactor = 10000 * delta / resizableSize;
             }
+			//Log.d("VerticalLayout delta=", delta, ", nonres=", nonresizableWeight, ", res=", resizableWeight, ", scale=", scaleFactor);
+			// find last resized - to allow fill space 1 pixel accurate
+			Widget lastResized = null;
             for (int i = 0; i < _children.count; i++) {
                 Widget item = _children.get(i);
                 if (item.visibility == Visibility.Gone)
                     continue;
-                int weight = item.layoutWeight;
+                if (item.layoutHeight == FILL_PARENT || needForceResize) {
-                if (item.layoutHeight == FILL_PARENT) {
+					lastResized = item;
-                    resizableWeight += weight;
-                    resizableSize += item.measuredHeight;
-                } else {
-                    nonresizableWeight += weight;
-                    nonresizableSize += item.measuredHeight;
                 }
 			}
+			// final resize and layout of children
+            int position = 0;
+			int deltaTotal = 0;
             for (int i = 0; i < _children.count; i++) {
                 Widget item = _children.get(i);
                 if (item.visibility == Visibility.Gone)
                     continue;
                 int layoutSize = item.layoutHeight;
-                totalWeight += item.measuredHeight;
                 int weight = item.layoutWeight;
-                if (layoutSize) {
+				int size = item.measuredHeight;
-                    resizableWeight += weight;
+                if (needResize && (layoutSize == FILL_PARENT || needForceResize)) {
-                    resizableSize += item.measuredHeight;
+					// do resize
+					int correction = scaleFactor * weight * size / 10000;
+					deltaTotal += correction;
+					// for last resized, apply additional correction to resolve calculation inaccuracy
+					if (item == lastResized) {
+						correction += delta - deltaTotal;
 					}
+					size += correction;
+                }
+				// apply size
+				Rect childRect = rc;
+				childRect.top += position;
+				childRect.bottom = childRect.top + size;
+				childRect.right = childRect.left + contentWidth;
+				item.layout(childRect);
+				position += size;
             }
         } else {
             // Horizontal
@@ -157,8 +174,13 @@ class LinearLayout : WidgetGroup {
         Rect rc = _pos;
         applyMargins(rc);
         applyPadding(rc);
-        // TODO
+        ClipRectSaver(buf, rc);
-        _needDraw = false;
+		for (int i = 0; i < _children.count; i++) {
+			Widget item = _children.get(i);
+			if (item.visibility != Visibility.Visible)
+				continue;
+			item.onDraw(buf);
+		}
     }
 
 }

src/dlangui/widgets/styles.d

@@ -447,6 +447,29 @@ class Theme : Style {
 		return style;
 	}
 
+	// ================================================
+	// override to avoid infinite recursion
+	/// font size
+	@property override string backgroundImageId() const {
+        return _backgroundImageId;
+	}
+	/// minimal width constraint, 0 if limit is not set
+	@property override uint minWidth() const {
+        return _minWidth;
+	}
+	/// max width constraint, returns SIZE_UNSPECIFIED if limit is not set
+	@property override uint maxWidth() const {
+        return _maxWidth;
+	}
+	/// minimal height constraint, 0 if limit is not set
+	@property override uint minHeight() const {
+        return _minHeight;
+	}
+	/// max height constraint, SIZE_UNSPECIFIED if limit is not set
+	@property override uint maxHeight() const {
+        return _maxHeight;
+	}
+
 	/// create new named style
 	override Style createSubstyle(string id) {
 		Style style = new Style(this, id);
@@ -470,6 +493,6 @@ private __gshared Theme _currentTheme;
 
 static this() {
 	_currentTheme = new Theme("default");
-    Style button = _currentTheme.createSubstyle("BUTTON").backgroundImageId("btn_default_normal");
+    Style button = _currentTheme.createSubstyle("BUTTON").backgroundImageId("btn_default_normal").alignment(Align.Center);
-    button.alignment(Align.Center);
+    Style text = _currentTheme.createSubstyle("TEXT").margins(Rect(3,3,3,3)).padding(Rect(3,3,3,3));
 }

src/dlangui/widgets/widget.d

@@ -37,17 +37,16 @@ class Widget {
     /// height measured by measure()
     protected int _measuredHeight;
     /// true to force layout
-    protected bool _needLayout;
+    protected bool _needLayout = true;
     /// true to force redraw
-    protected bool _needDraw;
+    protected bool _needDraw = true;
     /// parent widget
     protected Widget _parent;
     /// window (to be used for top level widgets only!)
     protected Window _window;
 
-    this() {
+    this(string ID = null) {
-        _needLayout = true;
+		_id = id;
-        _needDraw = true;
     }
 
     /// accessor to style - by lookup in theme by styleId (if style id is not set, theme base style will be used).
@@ -82,7 +81,20 @@ class Widget {
     /// set margins for widget - override one from style
     @property Widget margins(Rect rc) { ownStyle.margins = rc; return this; }
     /// get padding (between background bounds and content of widget)
-    @property Rect padding() const { return style.padding; }
+    @property Rect padding() const { 
+		// get max padding from style padding and background drawable padding
+		Rect p = style.padding; 
+		Rect dp = style.backgroundDrawable.padding;
+		if (p.left < dp.left)
+			p.left = dp.left;
+		if (p.right < dp.right)
+			p.right = dp.right;
+		if (p.top < dp.top)
+			p.top = dp.top;
+		if (p.bottom < dp.bottom)
+			p.bottom = dp.bottom;
+		return p;
+	}
     /// set padding for widget - override one from style
     @property Widget padding(Rect rc) { ownStyle.padding = rc; return this; }
     /// returns background color
@@ -127,7 +139,7 @@ class Widget {
     /// returns widget content text (override to support this)
     @property dstring text() { return ""; }
     /// sets widget content text (override to support this)
-    @property void text(dstring s) {  }
+    @property Widget text(dstring s) { return this; }
 
     //==================================================================
     // Layout and drawing related methods