Set background to an listview - image

I want to set an background to my listview that have different size (depending the appearance of softkeyboard). My list view is in between the editboxes and I want my editboxes always to be visible (means I do not want to use adjustPan).
My problem comes in the moment when the android adjust the size of my listview and the background get tweaked. I want my background to remain the same, just to be cropped.
and I want to look something like this
Is there any style that I can add that will make the image act like this, the point is to do NOT do an resize and to fill the whole available area. And to DO something like a CROP , means to show as much as there is an space and then the rest just to be cropped.

I found some workaround for the problem I want to solve. I set the scaleType with "centerCrop" value and it seems to work fine.
I hope this will save time to someone else having this problem...

Try in your Manifest to add
android:windowSoftInputMode="adjustPan" or "adjustUnspecified"
for your <activity
Read more about values here:
http://developer.android.com/guide/topics/manifest/activity-element.html#wsoft

I would put the listview in a linearlayout and put the background on the linearlayout.
As for the textbox at the top, if you have not figured that out, use relativelayout.
Here is a good link about the view being re-sized by the keyboard:
http://groups.google.com/group/android-developers/browse_thread/thread/be5ffe40c2bc29f0?pli=1
Here is a good link for the button staying on top:
Add Image at above of listview

Related

Best way to represent list with image(using url) in Xamarin.Forms?

I want to create List View. In this List View, I will have following fields.
StackPanel
1- Image with 300 x 400 size
2- Text-Label Controls
1 Screen will hardly cover 1 and Half ViewCell.
Images will have ImageURL. I want to load image smoothly. I also want to make smooth scroll up/down with image appearing.
Can anybody please suggest me which control I should use?
If List View, which CacheStrategy I should use?
Note: For one of such functionality, I had used List View with default CacheStrategy. In that, I just faced 1 major problem of image appearing. When page initialize first time, it show image properly. But as soon as I scroll down or scroll up, image disappear or misplace. In that case, I had suffered a lot and removed image finally.
Please suggest appropriate way for above functionality.
Thank you.
For the listview, you should definitely use RecycleElement as the CachingStrategy. See here https://developer.xamarin.com/api/type/Xamarin.Forms.ListViewCachingStrategy/#Remarks
And because the images are URLs, you can use FFImageLoading. It will fade-in the image after it is downloaded (as opposed to appearing instantly after downloaded), and you can even specify a placeholder image to use while the image is being downloaded.

How to do a scale open animation in Flutter?

I'm trying to do this animation in flutter :
https://material.io/guidelines/motion/choreography.html#choreography-creation
My problem is that I have absolutely no idea how to do that.
As far as I know, widgets in flutter don't know their position nor the position or other widgets at all.
And you can't access context.size inside the build method.
I tried to use Hero animation to do it. Or ScaleTransition. But it's definitely not working.
You can use showMenu to dynamically show a popup menu at a given location. Consider using PopupMenuButton, which is an IconButton that automatically shows a menu when it is tapped. There's an example in the Gallery. If showMenu doesn't do what you want, you can copy the code in popup_menu.dart and customize it to make your own version. It uses CustomSingleChildLayout and PopupRoute.
If you just want to absolutely position a Material or Card on top of other elements, you can give it some elevation and use a Positioned within a Stack. You can use an AnimatedSize to adjust the element's size with a Curve. This won't interact with the back button on Android automatically, so if you want that, you may have to use addLocalHistoryEntry or PopupRoute.
If I understand you correct - you want to show square widget, and animation is not suitable at most because widget doesn't know its size.
In this case you can try MediaQuery.of(context).size.width - it returns width of your screen, so you can use it for calculating widgets size

In XCode 8, how can I make an image button with padding?

I have an button, and I told it which 'image' to use (setting the image in 'background' works too). I would like to make the image inside the button to be smaller than the button. I tried changing the content insets, the title insets, and the image insets, but none of them seem to be working. The content and image insets scoot the image around, but do not make it smaller.
I would like to accomplish this in the main.storyboard, and not do it programmatically, if possible.
Not the best solution but if you need any easy work around you can add the image as an UIImageView and then add a clear button over it with the padding u need

Working with a Custom Image Grid

I was looking for a custom image grid and found a similar question that had a really sweet component in an answer.
I downloaded the code and after some fiddling, I managed to get it to compile in DXE2. It looks really cool, but I can't get either scrollbar to show up. I also can't figure out how to dynamically control the images displayed. Or how to update the grid based on keyboard events.
Also, to get it to compile I had to remove the GR32 references; the library I downloaded had too many incompatibilities with DXE2 for me to resolve.
Any help would be greatly appreciated. This really looks like a killer component.
Update from Bill:
Here is a screenshot of incorrect thumbnail painting. I can not get the thumbnails to look like the screenshot from the component in question.
If the thumbnails were painted at the same XY as the rects painted in the first pass they would look much better. Any idea on what is going on?
... but I can't get either scrollbar to show up.
Well, there is no horizontal scrollbar. There is the property ColWidth that controls how much images are drawn in one row, depending on the control's width. You might update ColWidth in an OnResize event handler due to anchor settings, for example.
The vertical scroll bar appears automatically when not all images (incl. spacing) fit in the clientrect. The images are drawn on a TPaintBox and that paint box' size is updated as soon as the image count changes:
procedure TImageGrid.RearrangeImages;
begin
...
FPainter.Height := Max(ClientHeight,
FRowCount * (FRowHeight + FImageSpacing) - FImageSpacing);
The component inherites from TScrollingWinControl, so the scroll bar should modify accordingly. If not, then Bill has a workaround found as commented:
VertScrollBar.Range := FRowCount * (FRowHeight + FImageSpacing) - FImageSpacing;
I understand this obviously also works, but I really wonder why the scroll bar's range should be modified manually. Here in D7 I have no problem with a hidden vertical scroll bar.
... I also can't figure out how to dynamically control the images displayed. ...
The most easy way to fill the component is by assigning the Folder property to a path with images. Only the images with the file formats in the FileFormats property will be loaded. To specify the images manually (e.g. to combine multiple folders), use the FileNames property. When the Folder property is set, then the FileNames property is updated accordingly, but those file names are not stored in the DFM. When you change the file names (e.g. you delete one from the folder), then the Folder property is cleared and the component uses the FileNames property instead.
... Or how to update the grid based on keyboard events. ...
The only keystrokes currently implemented are Up, Down, PageUp, PageDown, Home and End which all scroll the control. What more key actions do you wish? It's a viewer.
Here is a screenshot of incorrect thumbnail painting. I can not get the thumbnails to look like the screenshot from the component in question. ... If the thumbnails were painted at the same XY as the rects painted in the first pass they would look much better.
While loading the images, a temporary rect is drawn with size ColWidth * RowHeight. All images are stretchdrawn within that size, so adjust your ratio of these properties to make the spacing equal everywhere. Note that you can also influence appearance with the ImageHorzAlign and ImageVertAlign properties.
Update:
The component you refer to is recently completely rewritten, and some of the answers above are outdated.
It now has a Propertional property that defaults to True, but when set False, it will stretch up the thumbs to whatever cell size you have set, independent from the original image sizes. Small images could remain narow though, unless you set the new Stretch property to True.
It now distinguishes between RowHeight and CellHeight, and ColWidth and CellWidth. The difference between both is CellSpacing.
The component does not descend from TScrollingWinControl anymore, but from TCustomControl and only the vertical scroll bar is added.

Displaying an image when hovering a label

I'm wondering if there is a simple and quick way of displaying an image when the user hovers a QLabel...
Since QLabel can be used to display QPixmap, I would like to display some kind of "preview" when hovering a QLabel...
Do you guys know how I could manage this ?
Thanks in advance !
You can set the tooltip to use html, including <img> tags. Will that do what you need?
As described in the docs, you can override the object's event handler if you need to do something fancier in a tooltip than can be done by default. (such as selecting a particular area of an image to put in the tooltip)
As long as you set the button size large enough, you should be able to capture the mouse-over events and display on mouse-over... but this seems like a somewhat strange way to go about things. Why not display all the images at first?
For those who are interested in the result proposed by jkerian :
Simply :
MyLabel->setToolTip("<html><img src="+MyImagePathAsString+"/></html>");
Will result in :
Thanks again to jkerian.
I don't know what kind of layout your QLabel is in, but I'm guessing it will cause weird layout changes if you just set the pixmap on the label when mouseovering it. Rather use a tooltip or just display a pixmap freely on the canvas.

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