Custom Icon Buttons in Power Apps with Hover Color

Using icons for buttons is a very common scenario in Power Apps and Microsoft has provided the Icon control to accomplish just that. But… there are only 106 across 4 categories which isn’t a whole lot when it comes to icons. So if you are making anything of any complexity you’ve likely already run out. Fortunately, that’s

Easiest Solution

Just use their stupid icons

Custom Icons

But what if you don’t want to use one of the very few icons they’ve provided? What if you found Flicon and would like your app to match the rest of Office 365 and use the Fluent / UI Fabric icons? Or perhaps Font Awesome or the Noun Project or something your kid drew?

Fortunately, there are still options! There is a pretty easy option laid out in the OKish Solution below and then a PITA Solution that works but there are several steps involved. I’ve included both, but I definitely think the PITA Solution is the way to go until Microsoft figures out something better.

OK-ish Solution

Use images but be satisfied with Border or Fill effects

PITA Solution That Works

What if you want more than just a changing background or border? You know, like how the icons themselves work in Power Apps? For this, we’ll need a custom icon as an SVG. These steps could be adapted to work with a PNG image, but SVG is very common among icon sets and provides a better result overall.

1. Get an SVG Icon

First step, get your icon! Font Awesome and the Noun Project both provide all of their icons in SVG format. However, I recommend using the Fluent Icons provided by Microsoft since that’s what’s being used everywhere else. For that, let’s head over to Flicon.io.

If you haven’t used Flicon.io before, just search for an icon you want to use or browse with the categories. Once you’ve got an icon in mind, hover over it and switch to the Export tab. You can mess around with colors if you’d like, but it isn’t really necessary for what we’re doing. Just click Save as SVG:

2. Edit that Icon

We need to edit the SVG file before it’s ready to be used. There are plenty of tools out there to do that, but I use a free, open-source tool called Inkscape. You can download it directly from the site or just install it from the Microsoft Store.

Open your icon in Inkscape. One thing you’ll notice is that most of the icons are square, but the image isn’t always centered. Don’t worry, we’ll account for that to ensure our icon is a centered square.

In Power Apps we can use an SVG as the Image for an Image control. The Image control has HoverFill as we showed above. We’re going to take advantage of that and create an inverse of our icon. This means we’ll be creating an image that is the background and leaves the part of the icon we want displayed transparent. This allows us to set the “color” of the icon using the Fill and HoverFill properties!

3. Create a Box

In Inkscape, draw a box (fill color doesn’t matter, but it shouldn’t have a stroke). The size doesn’t matter just yet. Grab the square tool and draw something. Don’t worry about making it perfectly square.

Click on your icon and look at the Width and Height displayed. Take note of the bigger of the two (mine happen to be the same):

Click on the square you just drew and put the value you just noted for both its width and height. Now you have a box sitting somewhere near your icon that is the same size as your icon’s largest dimension. If you want additional padding for your icon, add that to the box’s dimensions.

Now we’re going to line them up. Open the Align and Distribute panel (Object > Align and Distribute). Select both the box and your icon. Ensure the Relative to dropdown is set to Page then click the Center on Vertical Axis button followed by the Center on Horizontal Axis button. Your box should be totally covering your icon now.

4. Cut a Hole in a Box

With both the box and the icon selected (just select all if you clicked off of them), perform an exclusion (Path > Exclusion). You now have one object and it is the negative space around your icon (remember the color doesn’t matter).

You’ll notice we’ve got an extra space around the icon and the document size (seen as a black square above). This is because our icon wasn’t perfectly centered before. If your icon looks good, skip ahead. To fix it, however, go to Document Properties (File > Document Properties). In the Custom Size options group, expand the Resize page to content section and click Resize page to drawing or selection.

5. Optimize Your SVG

Let’s save our SVG. Although we can use the default format, there’s a lot of extra stuff added that we don’t need. So let’s Save as (File > Save As…) and change the type to Optimized SVG. In the dialog that pops up, here are the options I’ve chosen with the goal of reducing SVG complexity/length:

Let’s open up our SVG file using a text editor like Notepad. You should see some XML with a viewBox attribute and one or more paths. Let’s do a find for double quotes and replace them all with single quotes.

6. Use Your Icon in Power Apps

Although we can add an SVG file as media and use it that way, I like to have a little more control. So, let’s add an Image control to your App. In the Image property we’re going to replace SampleImage with some text. The first bit of text is just a string:

"data:image/svg+xml;utf8, "

This will let us use the SVG text directly. To do that we need to add the EncodeUrl function. So connect the text above with an & and enclose the SVG text (copied from notepad) in double quotes inside of the EncodeUrl function (don’t forget your closing double quote and parenthesis):

The icon is showing, wowee! Now we need to make that fill match the background (the black stuff shown above). So we can edit our SVG string to add fill='white' (or a HEX or RGBA value that matches your background which is white in my case).

Where did that icon go?! It’s still there, it’s just being sneaky.

7. Add Some Color

Now for the magic! Set the Fill property for the Image control (shown as Color in the properties window for some reason) and your icon shows up! WOWEE!

Now set the HoverFill to some other color and hold Alt to see the magic.

Hold down Alt to test it right in the Editor

Limitations

This is not a perfect solution and the fact that this is our best option is pretty frustrating. But… it gets the job done but with a few notable issues when compared to using the native icons:

  • That’s an annoying amount of work for each icon
  • No option to have the pointer cursor even when using it with an OnSelect action
  • Images sometimes get weird borders depending on the scaling
  • You need to keep your image ratio the same to avoid the background leaking out (set the Width to Self.Height and control just the Height)

Making a Game in PowerApps – PowerPush: Dungeon Explorer 3000!

During my day job I create PowerApps fairly regularly for both clients and internal use. The platform has come a long way in a very short amount of time and has gone from interesting idea to amazing enterprise accelerator. So what did I decide to do with all that enterprise capability? Create a game of course!

PowerPush: Dungeon Explorer 3000!

PowerPush is a Sokoban clone made entirely in PowerApps. It has 6 levels, 4 playable characters, music, sound effects, supports right and left handed players, and has only 4 screens.

Fair warning, there’s a lot of sweet techno loops

PowerPush is open source (in as much as PowerApps can be) and you can import it into your tenant to give it a whirl and take a peek under the hood. There are no data connections at all, so it really is as simple as importing and playing.

Get it here: PowerPush.zip

Why?

To push myself and learn some stuff I wouldn’t necessarily learn by creating another form wrapper app. Believe me, I learned a lot! Number one thing I learned was that PowerApps really isn’t a great platform for making games. However, I also learned several really cool techniques (“wonky hacks” might be a better term for several of them). I’ll talk more about some of these below but I’ll also be following up with some individual tips and tricks in the next few weeks.

How it works

There are a lot of pieces to this app, and the best way to understand it is to just download it and take a look. But here are some details about each of the screens:

Screen 1: Main Menu

When the app starts, several global variables and collections are initialized. The most important of which is the levels global variable. This is an array of level objects that define the tiles to be used and details about where the crates start and where they should end up:

The levels object is later processed into a set of context variables and collections to manage current state for the active level and provide details about which image to use for each tile and whether those tiles are solid, etc.

The main menu has some animation based on a timer, but otherwise there are simple controls to set global variables used on other screens (like the character).

Screen 2: Level Start

The level start screen simply shows the current level details along with a randomly selected “tip”. This screen uses the fade navigation to create a nice transition into the level. You can also click anywhere on the screen to skip the automatic navigation based on a short timer.

One of the key things it does, however, is to process the level object into some key collections:

Set(activeLevel,Last(FirstN(levels,currentLevel)).Value);
Set(tiles,{
    background: ForAll(activeLevel.background,{
        img: LookUp(imgMap,id=Left(Value,2),img),
        solid: Right(Value,1) = "1"
    })
});
ClearCollect(crates, ForAll(activeLevel.start.crates, {x:Value.x, y:Value.y}));
ClearCollect(torches, ForAll(activeLevel.start.crates, { on: false}));
UpdateContext({tip:First(Shuffle(tips)).Value})

More details will later be pulled out of the activeLevel object to set up initial state for the player, but the info above determines how many crates are visible and where they are along with key information about the tiles. By using an image map collection we can use the strings setup in the level (first 2 characters are the tile image and the last indicates if the tile should be “solid”).

This step greatly simplifies level design by making it a simple array of strings so that you can almost visualize the level while you design it. By processing it here, we get easily usable values in a collection that tiles can reference details from by index.

This is how we can have one screen for the main game with any number of levels! This lets us simply bind to a data model and write logic (movement) to update that model. This is the area that PowerApps really shines.

Additionally, we could easily provide multiple image maps to create “themes” for levels to allow the same logic to apply a completely different tile set. The tile objects could also be extended to provide an additional layer of tiles for foreground elements if we wanted using nearly the same logic.

Screen 3: Main Game

This is where all the levels are shown. The tile system is based on 140 images laid out in 10 rows of 14 columns. Each of these tile image controls hijack their own BorderThickness property to store their “index” value. This works because the BorderStyle is set to None (so that value isn’t used).

This “index” value is used to position each of the individual tiles (the number of tiles, size, rows, columns, etc. can all be changed through some simple global variables). The “index” is also used to pull what the image should be by referencing the tiles object’s background array (shown above).

While not easy, you can reference an item within a collection by index by using this non-obvious formula:

Last(FirstN(tiles.background,tile043.BorderThickness)).img

The actual movement logic is handled in a single spot. There aren’t really global functions in PowerApps, but I’ve got something pretty close in that I’ve added a timer with a Duration value of 0. Then I set the AutoStart to a context variable. In the OnTimerEnd action I update any variables as needed and finally set that same AutoStart context variable to false.

So now to call that “global function” I simply need to call an UpdateContext function. In that call I update any “parameter” variables the global function will reference and set the AutoStart variable to true. For instance, here is the OnSelect for the Left button of the virtual D-Pad:

UpdateContext({requestedMove:{x:-1,y:0,rot:ImageRotation.Rotate180},evaluateMove:true})

Just to show you the power of the “global function” approach, here is the OnSelect for the Down button of the virtual D-Pad:

UpdateContext({requestedMove:{x:0,y:1,rot:ImageRotation.Rotate90},evaluateMove:true})

Both of these calls are nearly identical with the only exception being the “parameter” variable requestedMove.

The key part, however, is that evaluateMove:true. This will cause the timer to start and because it has a Duration of 0 it immediately performs it’s OnTimerEnd actio. This was really important because the move evaluation logic is pretty complicated and I really didn’t want to cut and paste it with some minor tweaks between 4 different buttons. That would be pretty hard to maintain.

The actual move evaluation uses a series of If statements and looks at the tiles collection to determine the current positioning of objects to determine if the requested position of the player is open and what should happen (push a crate, play a grunt since he hit a wall, etc.). It’s pretty convoluted, but you can see that some pretty complex logic can be performed to update our positioning elements (which specific controls like the player or the crates are bound too). Because of the power of PowerApps, all of the controls redraw themselves automatically just by our editing the model!

"Handle movement";
"If no wall in this direction";
If(!Last(FirstN(tiles.background,(playerY+requestedMove.y)*14+playerX+requestedMove.x+1)).solid,
    "If no crate in this direction";
    If(CountIf(crates,x=playerX+requestedMove.x And y=playerY+requestedMove.y) = 0,
	    "No crate, just move the player";
        UpdateContext({playerX:playerX+requestedMove.x, playerY:playerY+requestedMove.y, playerRot:requestedMove.rot, playerPushing:false,playSndWalk:true});
        Reset(audWalk),
		"There is a crate, see if it is up against a wall";
		If(!Last(FirstN(tiles.background,(playerY+requestedMove.y*2)*14+playerX+(requestedMove.x*2)+1)).solid,
			"Not against a wall, check for another crate";
			If(CountIf(crates,x=playerX+(requestedMove.x*2) And y=playerY+(requestedMove.y*2)) = 0,
				"Push that crate!";
				UpdateIf(crates, x=playerX+requestedMove.x And y=playerY+requestedMove.y, {x:playerX+(requestedMove.x*2),y:playerY+(requestedMove.y*2)});
				UpdateContext({playerX:playerX+requestedMove.x, playerY:playerY+requestedMove.y, playerRot:requestedMove.rot, playerPushing:true,playSndWalk:true,playSndPush:true});
                Reset(audWalk);
                Reset(audPush),
				"Can't move the crate or player (crate against a crate), but update player look";
				UpdateContext({playerRot:requestedMove.rot, playerPushing:true, playSndGrunt:true});
                Reset(audGrunt)
			),
			"Can't move the crate or player (crate against a wall), but update player look";
			UpdateContext({playerRot:requestedMove.rot, playerPushing:true, playSndGrunt:true});
            Reset(audGrunt)
		)
    ),
	"Can't move the player (wall), but update player look";
	UpdateContext({playerRot:requestedMove.rot, playerPushing:false});
    If(Rand()<.5,
        UpdateContext({playSndHuh1:true});
        Reset(audHuh1),
        UpdateContext({playSndHuh2:true});
        Reset(audHuh2)
    )
);

"Check crate positions";
ClearCollect(prevTorches, torches);
ClearCollect(torches, ForAll(crates, {on:CountIf(activeLevel.start.targets, x=Value.x And y=Value.y)>0}));
If(CountRows(Filter(torches,on=true))  CountRows(Filter(prevTorches,on=true)),
    UpdateContext({playSndIgnite:true});
    Reset(audIgnite)
);

"Check for Win";
If(CountRows(Filter(torches,on=true)) = CountRows(activeLevel.start.targets),
    UpdateContext({finalDescent:true});
    Reset(audMusicWin)
);
UpdateContext({evaluateMove:false})

Screen 4: Credits

This is a really simple screen that has a gallery bound to a custom credits collection. Then the Y value of the gallery is set based on a timer value to provide the scrolling animation. The timer is on a loop, so the scrolling is too.

This screen really exists to thank the tile artists (used with permission, but still greatly appreciated) and to make my kids happy (they’re the testers listed above).

Lessons Learned

I’m going to post a few different techniques I used as separate articles over the next few weeks, but there are several pain points I identified that I’d love to see solved in the future. Here’s a few:

Need for a this operator

You refer to a control by it’s name in your formulas. This works great. Even better, if you copy one or more controls they’ll get renamed and all the formulas updated. This is super powerful. But… if you suddenly need to update that formula on multiple controls (say 140 tiles), you can’t just select them all and update their formula because all of those formulas are now unique because they refer to specific controls. Simply introducing a this keyword that would refer to the current control in it’s own functions would be awesome.

Related Idea Entry – Go Vote!

Additional Idea Entry – Go Vote!

Audio should pause in the editor

Currently, if you loop and play your audio file it will continue to play even in the editor. This is weird behavior since, for instance, the timer stops running in the editor. This means if you do something like add really annoying techno music (see video above), you’ll never escape it.

Related Idea Entry – Go Vote!

True Image Rotation is needed

Right now you can flip an image control horizontally or vertically and you can rotate in 90 degree increments. It would be far more powerful if you could specify an exact degree of rotation. This would make animations far better.

Related Idea Entry – Go Vote!

Custom Object Props Please

To simplify things, I shoved an index variable for the tiles, crates, torches, etc. into their border width property. This works because I wasn’t using this property (BorderStyle: None). This made creating multiple controls that knew what variables to pull from far simpler. However, it would be even better if we could just associate custom properties of a given type directly on controls instead of hijacking an unused property (since this could have unintended consequences).

Related Idea Entry – Go Vote!

Reference Media by Name (text)

When you assign an image to an image control you do so by the Media variable. This is true for other controls as well. This is fine, but it can make dynamic assignments difficult since the control will need to be able to reference (know about) the actual media variables directly. I solved this using an image map collection so that I could build strings and then find the referenced image that way. This works pretty well, but it would be even easier if there were just a Media(“MediaName”) function.

Related Idea Entry – Go Vote!

Support for Key Down Events

PowerPush was designed for touch controls on a phone using a simulated d-pad. This works, but is clunky for the web. It would be far nicer to move with the arrow keys. Unfortunately, there isn’t a key down event to do this.

Related Idea Entry – Go Vote!

Update

I demoed the game on the SharePoint Patterns and Practices General Development call on 1/24/2019. Check it out here: