I am newbi in android world and working on an android app.
I have used many of buttons and image buttons in my app.
Now i want to replace them with an background image. (So i can make nice gui easily)
I know i can use view listener and i can find the clicked x and y coordinate from onclick method.
But I want to how can i find which part of the image was clicked. Because different phones have different resolutions how can i do this efficiently ?
And one more thing, Is it good to handle gui this way ?
Thanks !
You first need to set the initial window width and height before execution of other code and load an image of quality based on the screen size. so for example you can have 3 sets of images of different size. One for 5 inch screens and below. Another for 7 inch tablets. Another for 10 and possibly another super high quality image for anything above. As many devices coming on in the near future are reaching resolutions much higher then previously developed for. Just run code initially that detects the initial window size at hand and load image based on resolution of that device. From their program as you plan to.
Also to jump on answer above. Detect rotation event and adjust image accordingly. and update accordingly. You are adding more programming of course but no reason what you are asking could not be done. Just a few extra events detection and you should be good to go to accomplish exactly what you are looking to do
AFAIK it is not good practice to handle the GUI this way. Mostly because android screen size is not standard and so you can never be sure that it will work perfectly in all the devices. You can ofcourse handle the events using onTouchListener and see which part of image was clicked from the coordinates in the MotionEvent Object. But, I would not recommend doing so.
Creating layouts of different screen sizes and handling the events using Buttons and ImageButtons will be good.
you can use android:background attribute for background images in the layout xml files...
however you also can set the background of UI element programatically
Related
As you can see in the photo I have a scaling problem with my design. Actually there is two problems. One involving a textview and one about scaling. I found out that the easiest solution for layout was to implement a background image to my RelativeLayout. (This may be a stupid approach i don't know.)
As you can see in the images, the text changes position on textview.setText("blabla"). And is creating visual problem. How would I go about fixing this?
Secondly, how would I solve the scaling issue on different devices? My initial plan was to make one background for each size. Like mdpi, hdpi and so on.. But how do I tell the app to choose between background? And is this even possible?
Am I doing it all wrong? :)
Positioning problem http://chk.no/bue/stackoverflow.png
I want my app to run on a wide variety of android devices in portrait only. I have a whole-screen background image that includes borders for other components. I want to place items like listviews/sponsor ads accurately within those borders... overlay them on top of the background in exactly the right place. Is using Framelayout the best/easiest way to do this? How do I make sure I get the listviews or sponsor ads in exactly the right place, and exactly the right size given that the background will be stretched to different dimensions for different devices? I've considered cutting up the background image instead but that seems like more work. What's the best approach? Thanks for any thoughts!
Unfortunately, this scheme is never going to work consistently across all screen sizes. If you want borders, you need to create 9-patch graphics out of those and assigne them as teh background to the UI item.
I wanna start a new project. A little "Jump n Run", but I have questions:
The levels will be bigger than the screen. How can I make a big Layout and edit it?
And how do the view "follows" the player, if he moves.
I dont want code samples. I only want basic ideas how to do it.
I suggest you have a look at the SurfaceView. It allows you to render bitmaps to the screen. In your case you could create a bitmap that is larger than the screen and have the user navigate it with the use of their finger (so you'll also have to also use your touchscreen). Basically what you will be changing when the user wants to go to a new location would be the src rect parameter in the drawBitmap method.
I hope this gets you started.
You could specify the layout to whatever pixel size you want (even if it's larger than any screen size would be), and then use scroll views to allow the user to scroll to other areas of the screen. Check out the Android developer docs on horizontal scroll view.
I am relatively new to Android development, and am developing an application with an image for a background. I need the ability to have text reliably and precisely placed in relation to certain points on the background image. I developed the application debugging on a Droid Charge. Everything looks fine there. However, I downloaded the application to a Droid X, and the text is a little off. I imagine I am missing some fundamental understanding about Android development, and would appreciate any help. Also, I believe this person is having a similar problem.
Screen sizes and precise element placement on Android
Well you need to understand that due to support of multiple screen, it's not wise to have a certain points or coordinates to draw your Views. If you want to draw a text according to a background position, then may be you should use a custom View where the background picture can work as the Background of your custom view and then you can place the text at the exact location.
Another idea would be to use a 9 patch drawable which is not stretchable (Background uses 9 patch drawable which stretches on changing the size of the view). However you have to supply different drawable for different screen densities then. I'd choose the first option, as it's easier.
PS: Tell me in comment, if you find any difficulty on applying any of the option.
I'm entirely new to Android development, and I'm interested in making a live wallpaper. I was thinking about looping a set of pictures instead of drawing the animation. Is this a possible approach? If possible is this a suitable or ideal way of doing it, does it eat up memory and would i need images with different resolutions because of the fragmentation?(hundreds of different devices)
Thanks in advance :)
Sure, it should be fairly simple.
The main part of the Wallpaper engine is the Drawing of course. You need to handle the drawing manually, there is no easy way to loop through images... you need to code it. You will have to continuously monitor the time which has passed and adjust the displayed image based on that. You are given a Canvas object to draw to and it is all done during run-time in code.
The Wallpaper engine class has a event called onSurfaceChanged which gives you the width and height of the Surface which you will be drawing to. It will be called everytime the screen dimensions change (like if the phone is put into Landscape mode for instance). You need to have code that will handle any combination of width or height for all the device types out there. You will need to decide if you are going to stretch, center, tile or crop (Or a combination of those) the source images to fit any particular screen size. I would recommend scale to fit so that the image is either taller or wider than the screen and center the image either vertically or horizontally (cropping the extra bits) once that is done. I personally just use one source size and resize it to fit. You can opt to use several source files if you want which is the recommended approach I believe, but it's a little confusing.
I would start by creating a Live Wallpaper which just draws something basic like a shape to the screen. Then work out how to display an custom image and take it from there.
Good luck
You will need to be very careful about memory if taking a frame approach to animation--probably will not be possible to animate full frames--much more practical to move sprites on a background. See, fr'instance: http://davidjhinson.wordpress.com/2010/05/19/scarce-commodities-google-android-memory-and-bitmaps/
what if you have a png frame animation that is set at a certain x and y position that sits in a spot on the background image, both would have to be rescaled