Items will be displayed in a GridView:
<GridView
android:id="#+id/month_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="#dimen/activity_half_horizontal_margin"
android:paddingRight="#dimen/activity_half_horizontal_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:stretchMode="columnWidth"
android:horizontalSpacing="4dp"
android:verticalSpacing="4dp"/>
The layout for the items used to be generated in code:
private LinearLayout getMonthImageView() {
LinearLayout layout = new LinearLayout(context);
layout.setOrientation(LinearLayout.VERTICAL);
TextView text = new TextView(context);
text.setGravity(Gravity.CENTER);
text.setSingleLine();
layout.addView(text, 0);
ImageView image = new ImageView(context);
image.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
image.setAdjustViewBounds(true);
layout.addView(image, 1);
return layout;
}
I've refactored that part to come from an xml layout file instead:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/month_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:singleLine="true"/>
<ImageView
android:id="#+id/month_icon"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerInside"
android:adjustViewBounds="true"/>
</LinearLayout>
This had an unwanted visible effect: the gap between the items in the GridView has grown larger, as if the items had acquired some padding or margin (which is clearly not the case). Why is that? What is the difference of the items being generated in code versus coming from an xml layout file? How can I make the items scale up again?
Before (code layout):
After (xml layout):
I see some potential issues, but it's hard for me to say exactly what, without an image description of your problem.
You might wanna check out these few things:
If you're inflating LinearLayout, you should probably avoid android:layout_height="match_parent", because it takes up maximum space (usually the whole screen) even though you might not need it.
I'm thinking ImageView probably shouldn't be equal to parent, but have a distinct size.
This way also, it takes up maximum space in its parent, which it might not need.
My advice is, try a RelativeLayout, with the android:layout_width="match_parent" and android:layout_height="wrap_content.
Then use different layout_align options to align everything on top, and give some specific dimensions to your ImageView.
That's just my guess, I might be wrong though.
Related
I want to display a horizontal list of scrollable buttons at top of the phone screen containing 30 items, for this purpose I am using a HorizontalScrollView with a LinearLayout with "horizontal" orientation as it's child but the linear layout is not taking up the entire phone width even on setting its width as "match-parent". Here's the code :
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:layout_gravity="center">
<GridView
android:id="#+id/gridView_horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:stretchMode="columnWidth" />
</LinearLayout>
</HorizontalScrollView>
Here is shown in the image that linear layout is not taking up the entire space and LinearLayout is only covering some of the space. Also on changing the size to a fixed size, I noticed that the HorizontalScrollView was actually behaving like a vertical Scroll View only.
NOTE: Also if there is an alternative way to display a horizontal list of buttons with 30 items with numbers from 1 to 30 on it, please suggest it.
To achive this easily you may use Recyclerview with Horizotanl Layout Manager.For Example
recycler_view.setLayoutManager(new LinearLayoutManager(MainActivity.this, LinearLayoutManager.HORIZONTAL, false));
I don't think you need a HorizontalScrollView with a nested LinearLayout for what you are trying to achieve. It would be a better idea to simply use a horizontal RecyclerView if your button layouts are similar and the functionality of the buttons is similar too. Refer to this answer for help https://stackoverflow.com/a/40584425/9119277
Firstly, I am new to android so if I have missed something basic I apologise.
I have a page which has two ListViews side by side, both with varying amounts of content. I also have a TextView above the ListViews and another TextView below the listviews. These text view boxes change based on items selected in either of the two ListViews.
These two ListViews sit side by side, taking up half of the screen each, while a Textview sits directly above and directly below, both centred to the page. An image is shown below.
This is the page looking normal on load.
The problem is when I select an item from either list. I have a feeling I am missing some XML properties, but I am not sure which properties or if this is even the case. When an item is selected, let's say from the ListView on the right, the TextView at the bottom is updated with text taken from an array. The ListView also decides to change the width and I am not sure why this is.... I don't want the ListView to change width. I want it to remain taking up half of the page and half of the page only.
This is the page after an item from the right ListView has been selected.
I would also like to keep things in RelativeLayout. I also believe it is only an XML issue and not to do with the adapter or any other code so I will not include that for now. I can include it if required.
Any help would be great. Thanks in advance.
content_titles.xml my activity xml file
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".TitlesActivity">
<ListView
android:id="#+id/unlocked_titles_list"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:longClickable="true"
android:layout_below="#+id/current_title"
android:layout_alignEnd="#+id/requirements"
android:layout_marginEnd="26dp"
android:layout_above="#+id/requirements">
</ListView>
<TextView
android:id="#+id/current_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="65dp"
android:text="Current Title: Novice"
android:textSize="24sp"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"/>
<ListView
android:id="#+id/locked_titles_list"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignStart="#+id/requirements"
android:layout_marginStart="28dp"
android:layout_above="#+id/requirements"
android:layout_below="#+id/current_title"/>
<TextView
android:id="#+id/requirements"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="34dp"
android:text="temp"
android:textAlignment="center"
android:textSize="24sp"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"/>
</RelativeLayout>
activity_listview.xml used as the individual rows of the ListViews
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/label"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dip"
android:textSize="16dip"
android:textStyle="bold" >
</TextView>
The problems with layout could be caused by ScrollView to be the wrapper
I stumbled upon some note in http://developer.android.com/reference/android/widget/ExpandableListView.html
"...Note: You cannot use the value wrap_content for the android:layout_height attribute of a ExpandableListView in XML if the parent's size is also not strictly specified (for example, if the parent were ScrollView you could not specify wrap_content since it also can be any length. However, you can use wrap_content if the ExpandableListView parent has a specific size, such as 100 pixels."
I removed wrapping ScrollView and linear layout started working properly. Now its only to understand how to wrap the stuff to ScrollView. God help me
But anyway this is really weird behavior. I think that fill_parent is not really correct wording. When using heirarchyviewer tool I always see WRAP_CONTENT and MATCH_PARENT values for layout_width and leayout_height. So probably fill_parent is actually means match_parent which puts me in cognitive dissonance.
You have your layout_width properties set to wrap_content. This means that they could change as the data changes. I would recommend putting your ListViews in a LinearLayout with orientation:horizontal and set the amount of space that each element takes up with layout_weight. Here is a relevant SO question What does android:layout_weight mean?
I am developing an app in which I want to add textviews in a column-wise order. Atmost 3 textviews can fill horizontally the screen width. If there are more than 3 textviews to be added, the new ones should be added in the next row, and so on. See the diagram below-
---1st---------------2nd--------------3rd
---4th----------------5th-----and so on
I know we need to use a nested linear layout with different orientation parameters. But how do I get around this "maximum 3 textviews per row constraint". I know that this has to do something with the weight parameter. The code I have written so far is-
LinearLayout out = (LinearLayout) findViewById(R.id.linear_params);
TextView mView = new TextView(this);
mView.setText("placeholder");
mView.setLayoutParams(new LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT));
out.addView(mView);
And for the layout I have written-
<LinearLayout
android:id="#+id/out
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_margin="5dp">
<LinearLayout
android:id="#+id/in
android:layout_width="match_parent"
android:layout_height="10dp"
android:layout_gravity="center_horizontal"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:orientation="horizontal">
<TextView ... />
</LinearLayout>
</LinearLayout>
How should I modify the above xml and code so that I am able to place the views dynamically as required ?
The correct way to do this will be to use a GridView Component with three columns. It will allow you to add the views as well.
If you use LinearLayout you will have to use weights and keep adding new LinearLayout per row, this will take a lot of processing for calculations and overdrawing as well.
Using GridView will help to avoid writing the code to calculate and add every row and every view and will keep the layout optimized as well.
I've observed a behavior with layout_weight that I can't explain. The following is a trivial example:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:text="This is a very very very very very very very very very very very very very very very long string."
android:layout_weight="1"
/>
<View
android:layout_width="32dp"
android:layout_height="32dp"
android:layout_gravity="center_vertical"
android:background="#ffffffff"
/>
</LinearLayout>
In a QVGA display, the TextView wraps the text. The white square is displayed to the right of the text.
However, if I remove android:layout_weight="1" from the TextView, the TextView now takes up the entire display width. The white square is no longer displayed.
Why would layout_weight in the TextView affect whether or not the white square is displayed? Shouldn't the View with the white background always be assigned 32dpx32dp first? (It makes no difference if the view were any other types - ImageView or TextView).
The problem I was working on is that I want the white square to always be displayed to the right of the TextView (whether or not the text is wrapped), but I don't want any empty space between the TextView and the white square. (If I add android:layout_weight="1" to the TextView, then there is a gap if the text is not wrapped.)
Any help would be appreciated!
To answer my question #1: One thing I learned by looking at the source for LinearLayout: Not only does layout_weight assign unused space to a child, it also shrinks a child with layout_weight if the child extends beyond the bounds of the LinearLayout. That explains why a TextView with wrapped text is shrunk in my layout.
As for the answer to my question #2, I think you meant android:toRigthOf instead of android:layout_alignRight. Using a RelativeLayout instead of a LinearLayout doesn't change the layout behavior. The tricky part is placing a view immediately to the right of a TextView, without gaps, whether or not the text is wrapped. Setting a maxWidth would limit the TextView's width, but that solution doesn't scale across portrait/landscape and different display dimensions.
Solution - Looks like Dyarish's solution is the best available. My layout problem exists regardless of the layout you use. The key is to set a maxWidth for the TextView so that it doesn't take up the all of the horizontal space in the layout. Because hardcoding a android:maxWidth value in the TextView doesn't scale across different displays, setting the maxWidth at runtime, as Dyarish suggested, is a good solution.
Hopefully this is what you are looking for.
First off, here is a great resource I found for Creating UI's.
layout_weight - Specifies how much of the extra space in the layout to be allocated to the View.
If you want to ensure that the white square is always to the right of the textview, you can use a Relative View, and add the parameter to the view. android:layout_alignRight="+id#yourTextViewID". This should always make the box appear right beside the textView area. You should probably also add something like android:maxWidth="250px" This will ensure that you don't push the white box completely out of the screen.
Here is a code sample:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<TextView
android:layout_width="wrap_content"
android:maxWidth="250px"
android:id="#+id/TextForWhiteBox"
android:layout_height="wrap_content"
android:layout_gravity="center|left"
android:text="This is a very very very very very very very very very very very very very very very long string."
/>
<View android:background="#ffffffff" android:layout_width="32dp" android:layout_height="32dp" android:id="#+id/view1" android:layout_toRightOf="#+id/TextForWhiteBox"></View>
</RelativeLayout>
You could also add to the View:
android:layout_alignTop="#+id/TextForWhiteBox" android:layout_alignBottom="#+id/TextForWhiteBox"
to make the white box the same size as the TextView.
Firstly I've tested the code from my other answer and it does exactly what you've described you've wanted. (unless I'm misunderstanding what you are asking for). You definitely do not want to use the android:layout_alignRight which is not what is in the code sample. That would simply keep the box on the right hand of the screen and not be affected by the textview at all. This sample uses android:layout_toRightOf="#+id/TextForWhiteBox" which is possible due to it being a relative layout. Since the Relative Layout allows you to place objects in relation to others. That line will always place the box just to the right of the textview with no gaps.
As for the screen orientation changes:
When the orientation changes it creates a new instance of the view.
Here is a simple solution.
//Add to oncreate in your Activity
private TextView textStatus;
textStatus = (TextView) findViewById(R.id.TextForWhiteBox);
// This get's the width of your display.
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
int width = displaymetrics.widthPixels;
// Now you know the screen orientation, and it's width. So just set the maxwidth of the text view to match the display width - the pixels of your white box.
textStatus.setMaxWidth(width - 32); // 32 is here because you already know the size of the white box. More logic is needed to dynamically get this value, because you would need to wait for the activity to be fully created.
}
Here is the main.xml I used:
<?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"
android:orientation="horizontal"
>
<TextView
android:layout_width="wrap_content"
android:id="#+id/TextForWhiteBox"
android:layout_height="wrap_content"
android:layout_gravity="center|left"
android:text="This is a very very very very very very very very very very very very very very very very very very very long string."
/>
<View android:background="#ffffffff" android:layout_width="32px" android:layout_height="32px" android:id="#+id/view1" android:layout_toRightOf="#+id/TextForWhiteBox"></View>
</RelativeLayout>
You might need some additional logic to keep screen values.
This code has been tested, you should be able to literally copy and paste this to work as you asked.
Also depending on your logic you could use something like this to return the screen orientation.
int orient = getResources().getConfiguration().orientation;
Hope this helps!
If this helped you, please click the accepted button. =) Cheers!
How can I get a LinearLayout (or any other ViewGroup) to assume the size of it's child views rather than assuming the size of the background image?
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/large_image300x300pix">
<TextView android:id="#+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello world!"/>
</LinearLayout>
The linear layout becomes the same size as the background image.
How can I get my linear layout to assume the same size as the textview?
OK, so this thread is a little old, but I have a solution that someone might someday find useful. I think Android has problems scaling large images down, so the LinearLayout size ends up getting bumped by the background drawable bitmap, and the ImageView ends up forcing up the size of the parent container.
Unless you use a relative layout. You can make the ImageView relative to the position of the LinearLayout, even when the ImageView is behind the layout in the parent. My solution looks something like this:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
android:src="#drawable/activation_popup"
android:scaleType="fitXY"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_alignTop="#+id/activation_layout"
android:layout_alignBottom="#id/activation_layout"
android:layout_alignLeft="#id/activation_layout"
android:layout_alignRight="#id/activation_layout"
android:contentDescription="#string/act_code_label" />
<LinearLayout
android:id="#id/activation_layout"
android:clipToPadding="true"
android:padding="25dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
<!-- LinearLayout wraps a bunch of smallish views here -->
</LinearLayout>
</RelativeLayout>
I tried this on a top of display sizes and OS versions, seems to work great. Note that the padding in the LinearLayout is a trick to make space for a shadow border in the background image graphic. The LinearLayout doesn't need any relative positioning because top left is assumed.
You can create a FrameLayout and put an ImageView and your LinearLayout there. So you'll be able to configure the layout of your background image.
This happens because the Android view calculates its minimum size based on its background drawable size.
Check my answer here in this another post which covers the same problem which will help you to achieve your layout configuration.
If your image lends itself to being converted to a scalable 9-patch image, then doing that would cause the background to scale around the TextView.
I believe the best solution here is to set android:clipToPadding="true". What this does is excludes the padding for the main layout and wraps your layout to its children.