I generated an app with Microsoft PowerApps, but the delete button is missing a confirmation and deletes records a bit too easy. Is there an option to ask something like "are you sure?".
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| Need some delete confirmation |
Solution
There is no out of the box option, but you could change the delete button action a little bit. In this example we will add two more hidden buttons (Confirm and Cancel). The Delete button will unhide these buttons. The Confirm will then do the actual delete and the Cancel will hide the buttons again.
1) Create variable
The first step is to create a Boolean variable for this screen that will be used to show or hide buttons. In the screens pane on the left side click on the screen with the Delete button. Then add the following expression in the OnVisible property: UpdateContext({isVisible: false}). Now you have a variable called isVisible.
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| Add screen variable with value 'false' |
2) Add Confirmation and Cancel icons
Add two icons to your screen via the Insert ribbon. One for the Confirmation action and one for the delete. Also add a label above it with a text like "Are you sure?".
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| Add icons and label |
3) Move delete code
Now Cut and Paste the OnSelect code from the Delete button to the Confirm button and change the Delete button code to UpdateContext({isVisible: true}). This will change the variable value from false to true.
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| Switch delete code |
Add the following 'reverse' code to the OnSelect of the Cancel button: UpdateContext({isVisible: false}). This will change the variable value back from true to false.
4) Hide buttons and label
Since we don't want to show the icons when you haven't clicked on the delete button, we need to change the Visibily property of the two icons and the label. We will replace the default value 'true' to the isVisible variable.
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| Change Visibility |
The intermediate result is a delete button with a confirmation.
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| Delete with confirmation |
5) Disable other buttons
To finish it off we can disable the other buttons so that the user has to confirm or cancel the delete. To accomplish this we need to adjust an expression in the DisplayMode property of the Delete and Edit button. You need to add: && !isVisible to the if contruction. To make it a little more visable that the buttons are disabled you could change their disabled font color to grey.
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| Final adjustments |
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| The result |
Summary
In this post you learned how to add a confirmation visual to a delete button and learned how to add and use variables to change properties of items on your screen (because you cannot use code like: btnCancel.Visible = true).
The (value of the) variable is only usable on this screen. Other screens cannot use it. In a next post we will show you how to pass values from one screen to another screen.
Note that Microsoft PowerApps isn't part of Azure, but part of Office 365. However this tool could be very useful in Business Intelligence / Data Warehouse projects to replace manually created Excel / CSV source files with for example forecast data or simple lists that don't come from a source system. Users often 'accidentally' damage such files for example by adding or deleting columns. With PowerApps you can prevent that. An other great way to use Power Apps is within Power BI as an input form, but more about that in a next blog.
