Transparent or Invisible - android

I'm trying to use an ImageView without any background. I know that I can use
imageView.setVisibility(INVISIBLE);
and
imageView.setBackgroundColor(Color.TRANSPARENT);
I was wondering which one is more efficient? or any extra solution?

The two lines don't have the same purpose, so you don't really have to compare their efficiency.
The first one changes the view visibility, so the entire view is still drawn, takes the space in the layout, but is not visible at the moment.
On the other hand, an ImageView with an invisible background can still be visible if it has an android:src that is not null.
Here is a random example that uses the two together: it's an imageview with a transparent background, but with a source image, for which the visibility changes based on a certain condition, so it can be INVISIBLE or VISIBLE:
<ImageView
android:layout_width="50dp"
android:layout_height="50dp"
android:visibility="#{!obj.mealbox}"
android:background="#android:color/transparent"
android:src="#drawable/ic_list_sorting_close"
app:tint="#color/dish_icon_color" />
Since your purpose is to
use an ImageView without any background.
only the second option will work.

you can use imageView.setAlpha(127);

Related

How to return an original ImageView resource?

I have an ImageView defined in layout file like:
android:src="#drawable/ic_home"
During my application workflow I change the resource several times using
iv.setImageResource(some_id);
However if something going wrong I want to get my original resource back. Here is no method like ImageView.resetToDefault() and I do not see any other way than preserve original resource id in my program and set it when I need to return image back. However I need each time modify my code if I decided to change the resource attached to image view. So if somebody knows more elegant solution, then let me know.
PS I can see similar questions unanswered, so it seems Android design lack.
Guys, what about such work around? I make two image views stackable. So my image on top is invisible by XML definition. When I need update image, I just make it visible and reload image. When I want to get image default, I just hide it. Let me try.
After the view is inflated or set, set the ImageView resource programmatically.
defaultImageId = R.drawable.ic_home;
ImageView iv = (ImageView) findViewById(R.layout.my_image_view);
iv.setImageResource(defaultImageId);
//.... sometime later when you want to reset back to the "default"
iv.setImageResource(defaultImageId);
EDIT:
If you insist on keeping the resource id in XML only, ImageView does not allow for this to in its current state. You'll have to extend it and provide the functionality yourself. See the gist below for a working example. (I have tested it).
https://gist.github.com/enragedmrt/9143603
Although Enragedmrt provided a wonderful solution, I still came with a work around as below:
<ImageView
android:id="#+id/img_orig"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:src="#drawable/ic_default" />
<ImageView
android:id="#+id/img_towork"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:src="#drawable/ic_default" />
So when I want set to default I just do iv.setVisibility(View.INVISIBLE);

Copying android:drawableStart for RadioButtons in API 8

I need a custom radio button with a custom background, centered text, an icon immediately before the text, but without the default indicator.
Currently, I have the following code:
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:button="#null"
android:background="#drawable/bg_rbtn_custom"
android:drawableLeft="#drawable/icon"
android:text="Lorem ipsum…" />
The problem is the icon defined in drawableLeft, is pushed all the way to the left, i.e.
[icon]____Lorem ipsum…________
I need this:
____[icon]Lorem ipsum…________
The same thing happens when I use android:button="#drawable/icon; the icon is place at the left-most part of the View, and the text is then centred inside the left-over space (rather than being centred relative to the entire View). I am Android API 8, so I can't use drawableStart, so I need a way to duplicate its behaviour (at least I assume that's what it does). The text is dynamic, and will change at runtime, so I can't really hard code the padding.
My question is quite similar to this one, but that guy only needed a Button, but I need a RadioButton that'll work in a RadioGroup.
First thoughts would be to try
android:paddingLeft="#db"
where "#db" would be the number of pixels it would take to center everything
After trying your code and replacing the background and icon to local resources I had, I was unable to recreate the issue you are having. Could it be possible that the icon you are using has transparent pixels on its right edge?

Android Image Control

I have a big problem. I want to create a control for android in which the user sees an image and over lapping this image are smaller icons/image which are positioned relative to background image.
The smaller icons can be selected.
I really do not know how to go about it.
You could do this by having a clean image as background, like this:
and then you could have TextViews within a RelativeLayout with the names for example, and on every textView you can set the attribute clickable to your method.
Something like this:
<TextView
android:id="#+id/nevada"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/Oregon"
android:layout_marginRight="50dp"
android:layout_marginTop="21dp"
android:layout_toLeftOf="#+id/Cali"
android:clickable="true"
android:onClick="showState"
android:text="#string/Nevada"
android:textColor="#color/contact_map_text_color" />
and on your activity/fragment you will have your method that will be called by the View, in the example case: "showState"
Edit: its probably not the best approach but it certainly works

Would it be possible to let the user customize the color of a .9 drawable?

Pretty much what the title says. I'm wanting the user to have the choice to customize the boarder of a 9 drawable I have. Is something like that possible or do I need to use a different method? Right now, I think it won't work and it will mess up the 9 patch.
Can you post a picture of your 9-patch? It might be possible to extract parts of it to another type of drawable, then layer the customizable part (drawn with user defined color) under the fixed portions using a layer-list.
[Update] Based on the pic you posted, I'd trash the layer list idea, but we can still work something out. The idea would be to remove the colored border and internal dark background from the 9-patch entirely (fill that area in with the shadow color and opacity). Then nest 3 layouts in each other. The first would use the 9-patch as a background. The second would use the user-defined color as a background. The third would use your panel color as a background. The 9-patch would provide the proper margins to position the second (user-color) layout, and then you'd just add a layout_margin attribute to the second panel to position the inner most layout a few dps in.
<LinearLayout
android:id="#+id/PanelOuter"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/shadow_nine_patch">
<LinearLayout
android:id="#+id/PanelUserBorder"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/custom_border_width"
android:background="#color/dialog_border_color_default">
<LinearLayout
android:id="#+id/PanelContent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/custom_dialog_content_margin"
android:background="#color/dialog_inner_color">
</LinearLayout>
</LinearLayout>
</LinearLayout>
Of course, you'd be responsible for finding the PanelUserBorder view in code and calling setBackgroundColor() with the proper user-defined color.
maybe you could tint it by putting a 50% transparent view overtop the button.
after thinking about it i thought maybe you could transform the color by bitmap:
How to change Bitmap image color in android?

How can I get an image button's dimensions to make sense in android?

First of all, can I just say, I find laying out android UI's to be a frustrating experience? I used to think the XML layouts were simple and clean and awesome but every time I try to make anything with it I spend hours trying to do the simplest things!
In this particular instance I'm trying to make a simple horizontal bar that contains an image button of fixed size on the right and to the left of it I want an ImageView that takes up the rest of the available width. I see similar constructs all the time in the UI: the search box that appears at the top of the screen when searching, the text area and send button for composing text/googletalk messages, etc.
I've tried both a horizontal linear layout and a relative layout, and I can't get the button to look right in either one. My latest attempt has the following layout code:
It looks like this:
Using the hiearchyviewer indicates that both the imageview and the button have the same height (45px). And it shows the view dimensions and positions to be exactly what I'm looking for. Same height (differing widths of course since the ImageView is much wider). And they butt right up next to each other, centered in the Relative Layout. However the button as drawn on screen is obviously not taking up the full ImageButton view. I'm thinking it's something weird about the android system 9patch drawable used for the ImageButton background. But what do I know? I can't get it to look right no matter what I try.
How did you set up your RelativeLayout? Try to set it up like this:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent" android:layout_height="wrap_content">
<ImageButton android:layout_width="wrap_content" android:src="#drawable/icon" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:id="#+id/imgButton"></ImageButton>
<ImageView android:id="#+id/imageView2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:src="#drawable/red_button" android:scaleType="fitXY" android:layout_alignBottom="#+id/imgButton" android:layout_alignTop="#+id/imgButton" android:layout_toLeftOf="#+id/imgButton"></ImageView>
</RelativeLayout>
Hope this helps.
If dimensions are exactly how you are looking for , then in ImageButton and ImageView , use android:scaleType="fitXY" and check.
For simple case , I might use linearlayout with horizontal orientation with two buttons in it with proper weights.

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