I am creating a simple 'tooltip' subclass that is a rounded rectangle and a small triangle that will be 'anchored' to another view.
I created a UILabel subclass and am overriding 'drawRect' to shrink the main label area and draw a triangle.
The 'roundRect' represents the rounded rectangle portion that should contain the full text.
This all works great, except that I am having trouble getting the full text to be shown within the 'roundRect'. It appears that the text just doesn't show up for the last line (i.e. where the triangle now occupies).
One other thing to note, I am using auto layout and have setup the constraints for the 'tooltipLabel' to fill the screen as needed. This works as expected, as reducing/adding more text shows the appropriate sized tooltip. But it seems like I need to somehow inform the 'tooltip' or 'auto layout' that the text should be fitted into the 'roundRect' portion of the 'tooltipLabel'.
Screenshot #1 uses this 'drawTextInRect' method and you can see that the full text is being shown, but overlaps into the 'triangle' area (plus it has no insets, which is not the desired look):
override public func drawTextInRect(rect: CGRect) {
super.drawTextInRect(rect)
// super.drawTextInRect(UIEdgeInsetsInsetRect(rect, UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)))
}
Screenshot #2 uses this 'drawTextInRect' method with the desired insets (also adds the triangleHeight so that space is not written into with text) and you can see that it cuts off the 2nd and 3rd lines of text, as they don't 'fit' within the 'roundRect' bounds:
override public func drawTextInRect(rect: CGRect) {
// super.drawTextInRect(rect)
super.drawTextInRect(UIEdgeInsetsInsetRect(self.roundRect, UIEdgeInsets(top: 10, left: 10, bottom: 10+self.triangleHeight, right: 10)))
}
Here is the 'drawRect' override:
override public func drawRect(rect: CGRect) {
self.roundRect = CGRect(x: rect.minX, y: rect.minY, width: rect.width, height: rect.height-self.triangleHeight)
self.triangleBezier.moveToPoint(CGPoint(x: self.roundRect.midX-self.triangleWidth/2, y: self.roundRect.maxY))
self.triangleBezier.addLineToPoint(CGPoint(x: rect.midX, y: rect.maxY))
self.triangleBezier.addLineToPoint(CGPoint(x: self.roundRect.midX+self.triangleWidth/2, y: self.roundRect.maxY))
self.triangleBezier.closePath()
self.roundRectBezier = UIBezierPath(roundedRect: self.roundRect, cornerRadius: 5.0)
self.roundRectBezier.appendPath(self.triangleBezier)
self.tooltipColor.setFill()
self.roundRectBezier.fill()
super.drawRect(rect)
}
I would actually not be subclassing UILabel for this, and make your own tooltip class composed of the outer view and the internal label with auto layout constraints. The internal label determines the whole height of the view.
Something like this with appropriately rounded off corners/triangle:
Alternatively, use UITextView instead if you want to assign padding: Adding space/padding to a UILabel
Related
Is there a way to style the cursorDelegate on a TextArea/TextInput so that it ends up taller and thicker than the default one?
With the following code, I can currently get one that has the following properties:
Thicker than normal, at 4px wide
Taller than the rest of the text, with bits sticking out above/below the line as wanted. BUT, this only works until the user moves the cursor. Then, the vertical size gets clipped again, and can't be reset.
TextArea {
id: editor
cursorDelegate: Rectangle {
width: 4
property int vpad: 4
y: editor.cursorRectangle.y - (vpad / 2)
height: editor.cursorRectangle.height + vpad
}
}
It looks like the y and height bindings are getting overwritten by whatever sets those automatically internally.
Trying to overwrite these again myself using a onCursorPositionChanged handler on the TextArea fails, as you cannot write to cursorDelegate.
Managed to find a solution. Instead of setting these values in the normal way, you need to set these on the change handlers for those properties.
TextArea {
id: editor
cursorDelegate: Rectangle {
width: 4
property int vpad: 4
onYChanged: editor.cursorRectangle.y - (vpad / 2)
onHeightChanged: editor.cursorRectangle.height + vpad
}
}
This seems to resist the widgets auto behaviour that was overwriting our values.
I am conceiving a horizontal bar containing items.
They must all be of same width, having the same spacing between them.
They can expand as much as they want vertically (
stackblitz here
Problem:
How to automatically set the width of the row elements? Here I simply put a value that looks good: width:200px.
I want them to have a width dependent on the number of element per row.
What I tried:
Using elementRef in Horizontile (component holding the individual tiles, displaying with *ngFor) to get the width of this element:
currentWidth:number;
constructor(private el:ElementRef) {}
ngAfterViewInit(): void {
this.currentWidth=this.el.nativeElement.offsetWidth;}
it returns 5. (??) Using .width returns nothing. Also this is not recommended, I'd like another solution, less coupling.
I noticed I can make use of width:inherit; in the css of the individual tile component, which allows me to set the style from the horizontal list component.
<app-tile [style.width.px]="0.9*currentWidth/nDisplayedTiles" [tile]="item"></app-tile>
As the currentWidth value is zero, of course it doesn't work;
I tried setting it in % but the inherits css tag keeps the %, which is not the intended effect.
Why is the app-tile styling not cared about if inherits is not set?
I tried using ViewEncapsulation but it had no effect either.
This looks like a trivial matter though: did I just miss something?
You can use the offsetParent (link) width and create a method to return the value on each of the cells and call it in your [style.width.px], something like the following will work.
The HTMLElement.offsetParent read-only property returns a reference to the element which is the closest (nearest in the containment hierarchy) positioned ancestor element.
stackblitz
ngAfterViewInit(): void {
//added this as the compiler was throwing ExpressionChangedAfterItHasBeenCheckedError
setTimeout(() => {
this.currentWidth=this.el.nativeElement.offsetParent.clientWidth;
});
}
getWidth(): number{
let width:number = 0;
//you may need to change this value to better display the cells
let multiplier = 0.7;
width = (this.currentWidth * multiplier) / this.ndisplayTiles;
width = Math.round(width);
return width;
}
<app-tile [class]="'layout-tile'" [tile]="item" [style.width.px]="getWidth()">
</app-tile>
In my QML application I am drawing a triangle manually using "Canvas" object. The problem is I cannot figure out how to change the drawn object size each time I resize the main window.
Preferably, it would be convenient If I could simply redraw the triangle each time a window resize occurs. But I don't know how could this be done in QML. In bare QT, I guess I would subscribe to window size changed signal. What is the proper way of doing this in QML?
Edit: The program is described here: Change polygon color dynamically
In my main window there is a rectangle called rectMain. It is always the same size as the window. Then inside that rectangle there is another one, called rectTemp. In that rectangle I draw the canvas.
Edit 2: So far I have figure out how to react manually on window size changes:
property int lastWindowWidth: 0
property int lastWindowHeight: 0
function windowSizeChanged()
{
if ((lastWindowWidth == width) && (lastWindowHeight == height))
return;
console.log("New height: ", height, " New width: ", width);
lastWindowWidth = width
lastWindowHeight = height
}
onHeightChanged: windowSizeChanged();
onWidthChanged: windowSizeChanged();
What is the difference between width/height and implicitWidth/Height in QML? When should one set the implicit dimensions instead of the regular? When should one ask the implicit dimensions instead of the regular from a component/item?
Generally, usage of implicitHeight/Width only makes sense within reusable components.
It gives a hint, of the natural size of the Item without enforcing this size.
Let's take a Image as an example. The natural size of the image would map one pixel from the image file to one pixel on the screen. But it allows us to stretch it, so the size is not enforced and can be overridden.
Let's say now, we want to have a gallery with pictures of unknown dimension, and we don't want to grow but only shrink them if necessary. So we need to store the natural size of the image. That is, where the implicit height comes into play.
Image {
width: Math.max(150, implicitWidth)
height: Math.max(150, implicitHeight)
}
In custom components, you have a choice on how to define the sizes.
The one choice is, to have all dimensions relative to the components root-node, maybe like this:
Item {
id: root
Rectangle {
width: root.width * 0.2
height: root.height * 0.2
color: 'red'
}
Rectangle {
x: 0.2 * root.width
y: 0.2 * root.height
width: root.width * 0.8
height: root.height * 0.8
color: 'green'
}
}
In this case, there is no natural size of the object. Everything works out perfectly for each size you set for the component.
On the other hand, you might have an object, that has a natural size - that happens, e.g. if you have absolute values in it
Item {
id: root
property alias model: repeater.model
Repeater {
id: repeater
delegate: Rectangle {
width: 100
height: 100
x: 102 * index
y: 102 * index
}
}
}
In this example you should provide the user with information about the natural size, where the content does not protude the item. The user might still decide to set a smaller size and deal with the protrusion, e.g. by clipping it, but he needs the information about the natural size to make his decision.
In many cases, childrenRect.height/width is a good measure for the implcitHeight/Width, but there are examples, where this is not a good idea. - e.g. when the content of the item has x: -500.
A real life example is the Flickable that is specifically designed to contain larger objects than its own size. Having the size of the Flickable to be equal to the content would not be natural.
Also be careful, when using scale in custom components, as the childrenRect will not know about the scaling.
Item {
id: root
implicitWidth: child.width * child.scale
implicitHeight: child.height * child.scale
Rectangle {
id: child
width: 100
height: 100
scale: 3
color: 'red'
}
}
And to your comment: I just don't understand why it is better to set implicitWidth/Height instead of setting width/height of a component's root dimension.
implicitWidht/Height are not a necessety - QtQuick could do without them. They exist for convenience and shall be convention.
Rule of Thumb
When you want to set dimension of a root node of a reusable component, set implicitWidth/Height.
In some cases, set it for non-root-nodes, if the nodes are exposed as a property.
Do so only, if you have a reason for it (many official components come without any).
When you use a component, set width/height.
I don't have the definitive answer but I can tell you what I found out. First, from the documentation:
implicitWidth : real
Defines the natural width or height of the Item if no width or height
is specified.
The default implicit size for most items is 0x0, however some items
have an inherent implicit size which cannot be overridden, for
example, Image and Text.
but less informative for width:
width
Defines the item's position and size.
The width and height reflect the actual size of the item in the scene. The implicit size is some kind of inherent property of the item itself.1
I use them as follows: When I create a new item and it can be resized, I set an implicit size inside the object2. When I'm using the object, I often set the real size explicitly from the outside.
The implicit size of an object can be overridden by setting height and width.
an example: TextWithBackground.qml
Item {
implicitWidth: text.implicitWidth
implicitHeight: text.implicitHeight
// the rectangle will expand to the real size of the item
Rectangle { anchors.fill: parent; color: "yellow" }
Text { id: text; text: "Lorem ipsum dolor..." }
}
an example: MyWindow.qml
Item {
width: 400
height: 300
TextWithBackground {
// half of the scene, but never smaller than its implicitWidth
width: Math.max(parent.width / 2, implicitWidth)
// the height of the element is equal to implicitHeight
// because height is not explicitly set
}
}
1) For some elements, like Text, the implicit height depends on the (not-implicit) width.
2) The implicit size usually depends on the implicit size of its children.
Implicit size is supposed to be used when calculating size of an item based on its contents. Whereas setting width or height on a parent item may affect the size of its children it should never be a case, when you set implicit size.
Rule of thumb
Implicit size should only "bubble up", i.e. children should never
lookup for implicit size of their parent to calculate their own
implicit size, neither parent should try to force implicit size of its
children.
If you would try to set width on a component similar to layout, that initially calculates its width from the width (rather than implicitWidth) of its child item and that child is affected by the size of a parent, you would end up with a binding loop.
This is why the property exists - to break cyclic dependencies when calculating size of an item based on its contents.
I'm trying to create the following component:
Just for information, the blank space will contain a text control, and I'm creating a component that represents the black corner with the (i) icon and the "promotion" text.
The part I'm having issues with is this component representing the black corner with the diagonal text. The text has to be able to hold 2 lines. And the black corner has to be able to adjust to the text's size.
What's more, the text has a rotation...
I'm having some doubts on how to do this:
Should I have different controls for each text line?
Should I draw the text in the shape (after doing the rotation) or should I just overlap both components? [When I talk about drawing the text in the shape, I mean in the same way as asked in this question]
Is there any way to get the proper size of the triangle shape without doing some extravagant calculations?
And... do you have any "easier" ways to do this ?
A big thanks for any help you can provide :) I'm a little bit lost with this little component :)
Regards.
BS_C3
Edit 1:
The triangle may have 2 sizes: 1 size that will fit 1 line, and another size to fit 2 lines of text.
The text will be sent as a single string, so it will have to be automatically divided in two lines if needed
I was thinking of using graphics to draw the triangle shape and then use a mask to create the rounded corner --> This is because the same component will be used in other places of the application without the rounded corner
Flex is pretty good at updating group components to whatever size thier contents become, updating dynamically on the fly..
for what your suggesting, I'd probably create the "Promotion" group in the corner as a rectangle, rotate it and fit it to the corner like you want, then using a copy of the rounded rect you use as the maing component background, i'd make a mask to cut the "Promotion" component so you don't see the overlap.
Well, I finally wrote the class and this is the result:
public class Corner extends Canvas
{
private var infoIcon:Image;
private var text:Text;
private var triangle:Shape;
private var bgColor:uint;
public function Corner()
{
super();
infoIcon = new Image;
text = new Text;
text.rotation = -45;
text.width = 75;
text.maxHeight = 30;
text.setStyle('color', '0xffffff');
text.setStyle('textAlign', 'center');
text.y = 53;
this.addChild(infoIcon);
this.addChild(text);
triangle = new Shape;
}
public function build(bgColor:uint = 0x61113D):void{
this.bgColor = bgColor;
// info icon data
// set text
text.addEventListener(FlexEvent.UPDATE_COMPLETE, textHandler);
text.text = 'blabla';
text.validateNow();
}
/**
*
*/
private function textHandler(e:FlexEvent):void{
switch(e.type){
case FlexEvent.UPDATE_COMPLETE:
text.removeEventListener(FlexEvent.UPDATE_COMPLETE, textHandler);
drawTriangle();
break;
}
}
/**
*
*/
private function drawTriangle():void{
var h:int = 80;
// check if the text has 1 or 2 lines
if(text.height > 20)
h = 95;
// remove the triangle shape if it exists
if(this.rawChildren.contains(triangle))
this.rawChildren.removeChild(triangle);
// draw triangle
triangle = new Shape;
triangle.graphics.moveTo(0, 0);
triangle.graphics.beginFill(bgColor);
triangle.graphics.lineTo(h, 0);
triangle.graphics.lineTo(0, h);
triangle.graphics.lineTo(0, 0);
triangle.graphics.endFill();
this.rawChildren.addChildAt(triangle,0);
dispatchEvent(new MyEvent(MyEvent.CORNER_UPDATED));
}
...
}