Android RelativeLayout strange behaviour - android

I'm learning the relative layout and wrote a little test layout to simulate a login page:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="match_parent"
android:layout_width="match_parent">
<TextView android:id="#+id/labelUsername"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="username:"
android:layout_centerVertical="true"/>
<EditText android:id="#+id/txtUsername"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:hint="input username here"
android:layout_toRightOf="#id/labelUsername"
android:layout_alignBaseline="#id/labelUsername"/>
<TextView android:id="#+id/labelPassword"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="password:"
android:layout_below="#id/txtUsername"
android:layout_alignParentLeft="true"/>
<EditText android:id="#+id/txtPassword"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:hint="input password here"
android:layout_below="#id/txtUsername"
android:layout_alignLeft="#id/txtUsername"
android:layout_alignBaseline="#id/labelPassword"/>
</RelativeLayout>
What I want is putting the Username Label and Textfield above the Password Label and TextField. But the result is reverted, password are above!
I think the problem is the "android:layout_below" property in labelPassword, if I set it to below labelUsername, it works, however because the textfield is much bigger than label, the both textfields are in this case overlayed. So i try to make the labelPassword below the txtUsername, but it performs strange, I don't understand.
By the way, is there any guideline when I build layout with Relative Layout?
What should I put there at first?
What should I put at last?
thanks!

I think what you are trying to achieve here is trying to get both the username and password fields vertically centered, and the password field below the username field. The error in your layout is that you only tell the username textview and edittext to center vertically, and relative layout centeres the layouts after having arranged them. So your username field is centered, while the password is left on top.
What you should do is tell the parent(RelativeLayout) to vertically center all its child elements.
For that simply remove this attribute from the "username" TextView element :
android:layout_centerVertical="true"
And add this attribute to your RelativeLayout element:
android:gravity="center_vertical" //tells RelativeLayout to vertically center all child elements
In this case i would recommend using a LinearLayout but you can continue using RelativeLayout for now. Hope it helps!

To answer your concrete question, it's because android:layout_centerVertical="true" rule you are applying to labelUsername.
It seems that the relative position doesn't work well, when the elements you are refering to, are centered. And it also doesn't make sense, in this case, because you probably want the whole form centered, not only the username fields and then put the password bellow.
You can put the elements in a containing element (another relative layout, or linear layout, or table layout, etc.) and center that element. That works. Or to center all the contents, you can add android:gravity="center" to the containing layout.

As you go through the different Layouts you will find that while Relative layout feels the most "natural" if you're used to positioning things via CSS, for example (with absolute or relative positions) the situation you're describing here calls for either Linear or Table layout. Table layout is probably your best bet for anything "form" related. Your table elements (columns) should have a layout_span attribute that details how many columns to go across (it's sort of analog to colspan in HTML).
I'm not sure what specifically is going wrong in your RelativeLayout above, and I'm sure that with adequate trial and error you could get it to do roughly what you want, but I strongly advise you to use the right tools for the job.
LinearLayout is also a terrific tool (which you should remember can be nested indefinitely). Give your Layout a weightSum and then each item can have a layout_weight (they should add up to be the sum), while their layout_width should be 0dp (it's not intuitive, but that's how it works). That's also a terrific way to make things sit where they ought to.
Lastly the answer to the correct order in RelativeLayout is that the items are Z ordered from bottom to top, so the later an item appears in the sibling order, the higher its Z order is. Otherwise, their order is irrelevant.

Related

Vertically aligning suffix with tab space in android TextView

I have rows (of horizontal LinearLayout) with a TextView at the end that displays time. An this is how it looks:
Now I need the suffix (am/pm) in all rows to be aligned vertically. This is not the case in the above layout, as you can see, the last row is misaligned as the displayed time is longer.
I achieved this using the tab character \u0009. This means I would set the text to be for example "7:21\u0009\u0009pm". This produces desired result as show below:
However, I need to know if (1) this is the most efficient way and (2) that this would work on all android devices. If there is an alternative way to achieve this please let me know.
And here is an XML layout of a row for your reference:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="#dimen/prayer_time_row_height"
android:layout_marginLeft="48dp"
android:gravity="center_vertical"
android:orientation="horizontal">
<com.devspark.robototextview.widget.RobotoTextView
style="#style/text_subhead"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Today"
android:textColor="#color/material_light_secondary_text"
android:visibility="invisible" />
<com.devspark.robototextview.widget.RobotoTextView
style="#style/text_subhead"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Event"
android:textColor="#color/material_light_primary_text" />
<com.devspark.robototextview.widget.RobotoTextView
style="#style/text_subhead"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="12:06\u0009\u0009am"
android:textColor="#color/material_light_primary_text" />
</LinearLayout>
BONUS
Bonus points for pointing out a way to vertically align the hour-minute separator, i.e., colon character.
Maybe using tabs is the most efficient, but the gap is pretty big and not configurable. If you need all those rows in a single view group, you may try to check out RelativeLayout: align am/pm vertically on common left, and put hours to the left and on the baseline. This is the most flexible way, since you can control relative positions and margins, but computation-wise it's less efficient because it requires extra calculation upon laying out elements.
As per aligning colons — in most fonts (not just monospace) digits are designed to take equal space, so just align the numbers on the right (e.g. in relative layout) and it should do.
For the colon character, you could try using the character "\uee01" instead of ":". This is what google does with the clock in the lock screen.
https://github.com/android/platform_frameworks_base/blob/master/packages/Keyguard/src/com/android/keyguard/KeyguardStatusView.java#L247
You can use a 2-column TableLayout. The first column is the time without AM/PM and the second column is just the AM/PM. Set the gravity of the first column to "end" or "right" and the times will be lined up at the colons if you are using a fixed width font.

Android Layouts - Combining fills with wraps and gravities

I have an oddly organized activity with a number of LinLayouts inside of LinLayouts inside of LinLayouts (inside of LinLayouts) all so that each little section is organized correctly. Everything looks good except for one part.
I have a vertical LinearLayout with two things inside of it. One is another LinearLayout with weight set to 6, and below it is a TextView weight set to 1. What I want to do is have the height of the TextView to scale depending on the amount of lines in it. It could either be a one-liner sentence or maybe a four-line paragraph--I don't know what it'll end up. Then the LinLayout above it needs to fill in the rest of the height.
What layout_height settings do I need to combine to get this to work?
Finally figured it out. It's sort of weird, but this is what I had to do:
<LinearLayout
android:id="#+id/everything_but_description"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="horizontal" />
<TextView
android:id="#+id/description"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/paragraph" />
I had to have both set to "wrap_content" but give the one I wanted to fill the remaining space a weight WITHOUT giving the other one a weight. Very weird workaround but it works perfectly.

Border Lines for cells in GridLayout, TableLayout, or GridView?

I am trying to create a table/grid for some items within my app and I would like to have a border around each cell to divide the items up and have a coherent association of the setting with the item. This app will be used in an industrial setting where there may be people unfamiliar with Android that need to use this, thus trying to make it as easy as possible.
The table/grid will contain TextView, EditText, Spinner, and Button, and will also be scrollable (via ScrollView parent).
I read about the GridView and found that it (seems) to only be able to get items programmatically, please correct me if I am wrong. I felt that this was unnecessary since I know what items I want and where. Also, I have not tried adding items to a layout programmatically yet so I figured I would try the other options first. Also, the GridView documentation does not say one way or the other if border lines are automatically shown, or if you can have them shown at all.
I started with a TableLayout and was able to get everything except the border lines to work. I tried android:divider to get the lines but that didn't work. One thought I had was to create a bunch of TextViews with black backgrounds and ~2dp widths/heights to make my own border lines. This feels like a huge waste though. Then I also read the TableLayout documentation and found this: "TableLayout containers do not display border lines for their rows, columns, or cells."
I then tried the GridLayout and had the same results as the TableLayout. I tried padding and margins, neither worked. Also, the GridLayout documentation states: "The grid is composed of a set of infinitely thin lines that separate the viewing area into cells."
My questions are:
Is there an attirbute that I missed in TableLayout or GridLayout that will give me border lines via the xml?
If no, then will the GridView give me the lines I want?
Will I be able to add all the perviously mentioned items I want to the GridView?
I was actually able to achieve the desired look by setting the android:background="#000000" within the GridLayout view and then in the child items I set the android:background="#8CDD81" (just some green color) and combined with android:layout_margin="2dp" I was able to get the "grid" lines that I wanted. Thanks to CommonsWare though for getting me thinking in a new direction that turned into a solution.
EDIT:
This does not work quite as anticipated. You need the android:layout_alignLeft/Right which are only available via RelativeLayout in order to get just the right width on the child items. Haven't tested this yet using this idea, child items within RelativeLayout within GridLayout.
Is there an attirbute that I missed in TableLayout or GridLayout that will give me border lines via the xml?
No.
If no, then will the GridView give me the lines I want?
No.
Will I be able to add all the perviously mentioned items I want to the GridView?
Yes, though how well something like a Spinner will work, I can't say.
The simplest way, off the top of my head, to give you the lines you seek is to have each cell of the TableLayout or GridLayout be some container containing the widget(s) for that cell, where you give the container a background that is your line. A ShapeDrawable could be defined in XML for that background, which will be nicely resizeable based upon the actual requirements of the cell.
For future visiters this is how I did it with TableLayout:
table.xml
<TableLayout android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#969696">
<!-- table heading -->
<TableRow>
<Button android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Name"
android:background="#d2d2d2"
android:layout_margin="1dp"
/>
<Button android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Address"
android:background="#d2d2d2"
android:layout_margin="1dp"
/>
</TableRow>
<!-- table data -->
<TableRow>
<TextView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Ahtisham"
android:layout_margin="1dp"
android:background="#f1f1f1"
/>
<TextView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Kashmir"
android:layout_margin="1dp"
android:background="#f1f1f1"
/>
</TableRow>
</TableLayout>

Android Eclipse placing a text view in specific places

I'm creating this in a XML file and want a text view to be placed in a specific spot.
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="200dp"
android:text="Text"
android:textColor="#color/blue"
/>
It's underneath the last button that was placed so it's around in the middle of the screen. I want it to be at the bottom of the screen of to the right.
Easy if you're using a RelativeLayout as parent.
android:layout_alignParentRight
android:layout_alignParentBottom
(check the capitalization, I'm not anywhere I can double check).
Using a RelativeLayout would be perfect if you would be specifying each views' positions. It is the most flexible layout among the Android Layouts.
Take a look at this tutorial. It discussed how to position views in a RelativeLayout.
I hope you can get ideas from it in solving your problem.

How to wrap text in textview in Android

Does any one know how to wrap text in TextView in Android platform. i.e if the text in textview exceed the screen length it should be displayed in the second line.
I have searched and tried the following:
android:scrollHorizontally="false",
android:inputType="textMultiLine",
android:singleLine="false"
But none work..
Can anyone suggest how can I do it.
Constraint Layout
<TextView
android:id="#+id/some_textview"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintLeft_toLeftOf="#id/textview_above"
app:layout_constraintRight_toLeftOf="#id/button_to_right"/>
Ensure your layout width is zero
left / right constraints are defined
layout height of wrap_content allows expansion up/down.
Set android:maxLines="2" to prevent vertical expansion (2 is just an e.g.)
Ellipses are prob. a good idea with max lines android:ellipsize="end"
0dp width allows left/right constraints to determine how wide your widget is.
Setting left/right constraints sets the actual width of your widget, within which your text will wrap.
Constraint Layout docs
For me this issue only occurred on Android < 4.0
The combination of parameters I used were:
android:layout_weight="1"
android:ellipsize="none"
android:maxLines="100"
android:scrollHorizontally="false"
The maxLines count seemed to be the random final piece that made my TextView wrap.
For the case where the TextView is inside a TableLayout, the solution is to set android:shrinkColumns="1" on the TableLayout. (Replace 1 with the column number the TextView you want to wrap is in. (0-indexed))
AFAICT, no other attributes are needed on the TextView.
For other cases, see the other answers here.
FWIW, I had initially gotten it to sort of work with
<TextView
android:id="#+id/inventory_text"
android:layout_width="fill_parent"
android:layout_weight="1"
android:width="0dp"
but that resulted in some extra empty space at the bottom of the Dialog it was all in.
Use app:breakStrategy="simple" in AppCompatTextView, it will control over paragraph layout.
It has three constant values
balanced
high_quality
simple
Designing in your TextView xml
<android.support.v7.widget.AppCompatTextView
android:id="#+id/textquestion"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:scrollHorizontally="false"
android:text="Your Question Display Hear....Your Question Display Hear....Your Question Display Hear....Your Question Display Hear...."
android:textColor="#android:color/black"
android:textSize="20sp"
android:textStyle="bold"
app:breakStrategy="simple" />
If your current minimum api level is 23 or more then in Coding
yourtextview.setBreakStrategy(Layout.BREAK_STRATEGY_SIMPLE);
For more refrence refer this BreakStrategy
You must use 2 parameters :
android:ellipsize="none" : the text is not cut on textview width
android:scrollHorizontally="false" the text wraps on as many lines as necessary
This should fix your problem: android:layout_weight="1".
By setting android:maxEms to a given value together with android:layout_weight="1" will cause the TextView to wrap once it reaches the given length of the ems.
OK guys the truth is somewhere in the middle cause you have to see the issue from the parent's view and child's. The solution below works ONLY when spinner mode = dialog regardless of Android version (no problem there.. tested it in VD and DesireS with Android =>2.2) :
.Set you spinner's(the parent) mode like :
android:spinnerMode="dialog"
Set the textview's(child custom view) properties to :
android:layout_weight="1"
android:ellipsize="none"
android:maxLines="100"
android:scrollHorizontally="false"
I hope this works for you also.
In Android Studio 2.2.3 under the inputType property there is a property called textMultiLine. Selecting this option sorted out a similar problem for me. I hope that helps.
Just was working on a TextView inside a layout inside a RecyclerView. I had text getting cut off, ex, for Read this message, I saw: Read this. I tried setting android:maxLines="2" on the TextView, but nothing changed. However, android:lines="2" resulted in Read this on first line and message on the 2nd.
Try #Guykun's approach
android:layout_weight="1"
android:ellipsize="none"
android:maxLines="100"
android:scrollHorizontally="false"
Also, make sure that parents width is not set to wrap content. This is the thing that I was missing.
I had the same problem. Following change made it work -
android:layout_width="wrap_content"
The ellipsis, maxLines, or layout_weight - all didn't make any difference.
Note - The parent width is also set as wrap_content.
All you have to do is to set your textview width.
android:layout_width="60dp"
you can change the width to your choice. Just type long sentence to check if it working like this
android:text="i want to be among world class software engineer"
I am using Android 2.2 and my textview will automatically goto the next line if it exceeds the screen.
If you would like to have the text goto the next line before the end of the screen, just add in (just put in your own dp value). This will be useful if you have a picture on the right of the text.
android:layout_marginRight="52dp"
Strange enough - I created my TextView in Code and it wrapped - despite me not setting anything except standard stuff - but see for yourself:
LinearLayout.LayoutParams childParams = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.WRAP_CONTENT);
childParams.setMargins(5, 5, 5, 5);
Label label = new Label(this);
label.setText("This is a testing label This is a testing label This is a testing label This is a testing labelThis is a testing label This is a testing label");
label.setLayoutParams(childParams);
As you can see from the params definition I am using a LinearLayout. The class Label simply extends TextView - not doing anything there except setting the font size and the font color.
When running it in the emulator (API Level 9) it automatically wraps the text across 3 lines.
Just set layout_with to a definate size, when the text fills the maximum width it will overflow to the next line causing a wrap effect.
<TextView
android:id="#+id/segmentText"
android:layout_marginTop="10dp"
android:layout_below="#+id/segmentHeader"
android:text="You have the option to record in one go or segments(if you swap options
you will loose your current recordings)"
android:layout_width="300dp"
android:layout_height="wrap_content"/>
The trick is with the textView width, try to make it dedicated number like:
<TextView
android:layout_width="300dp"
android:layout_height="wrap_content"/>
I've tried many solutions without any result, I've tried:
android:ellipsize="none"
android:scrollHorizontally="false"
the only one thing triggred the wrap option is the dedicated width
You need to add your TextView in a ScrollView with something like this :
<ScrollView android:id="#+id/SCROLL_VIEW"
android:layout_height="150px"
android:layout_width="fill_parent">
<TextView
android:id="#+id/TEXT_VIEW"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="This text view should act as header This text view should act as header This text view should act as header This text view should act as header This text view should act as header This text view should act as header This text view should act as header" />
</ScrollView>

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