My question is simple,
How to set my buttons layout_gravity programmatically?
I found this on internet, but it simply throws me a Nullpointer exception:
Button MyButton = new Button(this);
LinearLayout.LayoutParams lllp=(LinearLayout.LayoutParams)MyButton.getLayoutParams();
lllp.gravity=Gravity.RIGHT;
MyButton.setLayoutParams(lllp);
MyLinearLayout.addView(MyButton);
Any solution?
Java
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT);
params.weight = 1.0f;
params.gravity = Gravity.TOP;
button.setLayoutParams(params);
Kotlin
val params = LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT
).apply {
weight = 1.0f
gravity = Gravity.TOP
}
For gravity values and how to set gravity check Gravity.
Basically, you should choose the LayoutParams depending on the parent. It can be RelativeLayout, LinearLayout etc...
I'd hate to be resurrecting old threads but this is a problem that is not answered correctly and moreover I've ran into this problem myself.
Here's the long bit, if you're only interested in the answer please scroll all the way down to the code:
android:gravity and android:layout_gravity works differently. Here's an article I've read that helped me.
GIST of article: gravity affects view after height/width is assigned. So gravity centre will not affect a view that is done FILL_PARENT (think of it as auto margin). layout_gravity centre WILL affect view that is FILL_PARENT (think of it as auto pad).
Basically, android:layout_gravity CANNOT be access programmatically, only android:gravity.
In the OP's case and my case, the accepted answer does not place the button vertically centre.
To improve on Karthi's answer:
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.gravity = Gravity.CENTER;
button.setLayoutParams(params);
Link to LinearLayout.LayoutParams.
android:layout_gravity shows "No related methods" meaning cannot be access programatically.
Whereas gravity is a field in the class.
I had a similar problem with programmatically setting layout_gravity on buttons in a GridLayout.
The trick was to set gravity on the button layoutParams AFTER the button was added to a parent (GridLayout), otherwise the gravity would be ignored.
grid.addView(button)
((GridLayout.LayoutParams)button.getLayoutParams()).setGravity(int)
MyButton.setGravity(Gravity.RIGHT);
For layout_gravity use the answer stated by "karthi". This method sets gravity to place the children inside the view.
layoutParams2.gravity = Gravity.RIGHT|Gravity.BOTTOM;
use this to add mor than one gravity
If you want to change the layou_gravity of an existing view do this:
((FrameLayout.LayoutParams) view.getLayoutParams()).gravity = Gravity.BOTTOM;
Remember to use the right LayoutParams based on the Layout type your view is in. Ex:
LinearLayout.LayoutParams
KOTLIN setting more than one gravity on FrameLayout without changing size:
// assign more than one gravity,Using the operator "or"
var gravity = Gravity.RIGHT or Gravity.CENTER_VERTICAL
// update gravity
(pagerContainer.layoutParams as FrameLayout.LayoutParams).gravity = gravity
// refresh layout
pagerContainer.requestLayout()
This question is old but I just had the same problem and solved it like this
LayoutParams lay = new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.FILL_PARENT)
lay.gravity = Gravity.CENTER;
I use someting like that: (Xamarin and C# code)
LinearLayout linLayout= new LinearLayout(this);
linLayout.SetGravity(GravityFlags.Center);
TextView txtView= new TextView(this);
linLayout.AddView(txtView);
the SetGravity puts my textView in the center of the layout.
So SetGravity layout property refer to layout content
In case you need to set Gravity for a View use the following
Button b=new Button(Context);
b.setGravity(Gravity.CENTER);
For setting layout_gravity for the Button
use gravity field for the layoutparams as
LayoutParams lp=new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);
lp.gravity=Gravity.CENTER;
try this
hope this clears
thanks
If you want to put a view in the center of parent, you can do with following code..
public class myLayout extends LinearLayout {
public myLayout(Context context) {
super(context);
RelativeLayout vi = (RelativeLayout) ((LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(
R.layout.activity_main, null);
LinearLayout.LayoutParams cc = new LinearLayout.LayoutParams(
LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
cc.gravity = Gravity.CENTER;
this.setGravity(Gravity.CENTER);
this.addView(vi);
}
}
these code section make LinearLayout put the first view elements in the center of parent.
So, we system don't consider the initial width and high to arrange view in the center .
I do the code section well.
The rest of the answers are right, I want to add more explaination. The layout_gravity is about how to position the view in parent view.
You must set gravity **after method parentView.addView() ** was called. We can see the code:
public void setLayoutParams(ViewGroup.LayoutParams params) {
if (params == null) {
throw new NullPointerException("Layout parameters cannot be null");
}
mLayoutParams = params;
resolveLayoutParams();
if (mParent instanceof ViewGroup) {
((ViewGroup) mParent).onSetLayoutParams(this, params);
}
requestLayout();
}
And the problem of null pointer is because it's not calling addView before getLayoutParams().
The annotation was already said "This method may return null if this View is not attached to a parent ViewGroup or {#link#setLayoutParams(android.view.ViewGroup.LayoutParams)} was not invoked successfully. When a View is attached to a parent ViewGroup, this method must not return null."
to RelativeLayout, try this code , it works for me:
yourLayoutParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
Perfectly Working!!! None of the above answer works for me. In Xml file setting gravity and setting layout_gravity is different. Check out the below code
// here messageLL is the linear layout in the xml file
// Before adding any view just remove all views
messageLL.removeAllViews();
// FrameLayout is the parent for LinearLayout
FrameLayout.LayoutParams params = new
FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
params.gravity = Gravity.CENTER|Gravity.CENTER_VERTICAL;
messageLL.setLayoutParams(params);
messageText.setVisibility(View.GONE);
messageNoText.setVisibility(View.VISIBLE);
messageLL.addView(messageNoText);
Also check This,where you can find clear explanation about gravity and layout_gravity .
Most of above answer are right, so written a helper methods, so you can use it
directly in you project .
set layout_gravity programmtically
// gravity types : Gravity.BOTTOM, Gravity.START etc.
// view : can be any view example : button, textview, linearlayout, image etc.
// for single view
public static void setLayoutGravity(int gravity, View view){
((LinearLayout.LayoutParams) view.getLayoutParams()).gravity = gravity;
}
// for mulitple views
public static void setLayoutGravity(int gravity, View ...view){
for(View item : view)
((LinearLayout.LayoutParams) item.getLayoutParams()).gravity = gravity;
}
Modify the existing layout params and set layout params again
//Get the current layout params and update the Gravity
(iv.layoutParams as FrameLayout.LayoutParams).gravity = Gravity.START
//Set layout params again (this updates the view)
iv.layoutParams = layoutParams
I switched from LinearLayout.LayoutParams to RelativeLayout.LayoutParams to finally get the result I was desiring on a custom circleview I created.
But instead of gravity you use addRule
RelativeLayout.LayoutParams mCircleParams = new RelativeLayout.LayoutParams(circleheight,circleheight);
mCircleParams.addRule(RelativeLayout.CENTER_IN_PARENT);
int width=getResources().getDisplayMetrics().widthPixels;
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams
(width, width);
params.gravity = Gravity.CENTER;
iv_main_text = new HTextView(getContext());
iv_main_text.setLayoutParams(params);
iv_main_text.setBackgroundColor(Color.BLUE);
iv_main_text.setTextSize(60);
iv_main_text.setGravity(Gravity.CENTER);
iv_main_text.setTextColor(Color.BLACK);
FloatingActionButton sendFab = new FloatingActionButton(this);
FrameLayout.LayoutParams layoutParams = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
layoutParams.setMargins(32, 32, 32, 32);
layoutParams.gravity = Gravity.END|Gravity.BOTTOM;
sendFab.setLayoutParams(layoutParams);
sendFab.setImageResource(android.R.drawable.ic_menu_send);
Try this code
Button btn = new Button(YourActivity.this);
btn.setGravity(Gravity.CENTER | Gravity.TOP);
btn.setText("some text");
or
btn.setGravity(Gravity.TOP);
Related
I'm unable to center-align a child inside a LinearLayout that uses a fixed width. As far as I can see, this should be possible by setting the gravity flag on the LinearLayout but it doesn't seem to work.
Here is the code:
LinearLayout hbox = new LinearLayout(getContext());
hbox.setOrientation(LinearLayout.HORIZONTAL);
TypedValue typedValue = new TypedValue();
getContext().getTheme().resolveAttribute(android.R.attr.listChoiceIndicatorMultiple, typedValue, true);
CheckedTextView ctv = new CheckedTextView(getContext());
ctv.setCheckMarkDrawable(typedValue.resourceId);
params = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
ctv.setLayoutParams(params);
hbox.addView(ctv);
params = new LinearLayout.LayoutParams(200, LayoutParams.WRAP_CONTENT);
params.gravity = Gravity.CENTER;
hbox.setLayoutParams(params);
As you can see, the CheckedTextView uses WRAP_CONTENT so it should be possible to align it. Its parent LinearLayout uses a fixed width of 200 pixels and gravity set to Gravity.CENTER. Still, it isn't center-aligned but the checkbox always appears on the left side of the LinearLayout, not in the center.
Does anyone have an idea what's wrong there?
To answer my own question, setting params.gravity was wrong because this corresponds to the alignment of hbox within its parent. What I want, though, is to set the alignment of the children of hbox, so it has to be like this instead:
params = new LinearLayout.LayoutParams(200, LayoutParams.WRAP_CONTENT);
hbox.setLayoutParams(params);
hbox.setGravity(Gravity.CENTER);
Then it works.
You know this JoystickView from http://code.google.com/p/mobile-anarchy-widgets/wiki/JoystickView ?
Well, I tried to implement it. No Problems with it. I couldn't change It's size because I Added It programmatically. I somehow found out how to change the size, but now It's stuck in the upper left corner and everything I found for three hours got me a NullPointerException on the LayoutParams param I've created or was rejected because It wasn't castable or something to begin with.
public class GameActivity extends Activity implements JoystickMovedListener{
private GraphicsHolder mGraphicsHolder;
private String TAG = "GameActivity";
/*
* creates a new GraphicsHolder and sets it its ContentView
* the GraphicsThread is being included in the GraphicsHolder
*/
#Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
Log.d(TAG, "created");
FrameLayout gameScreen = new FrameLayout(this);
mGraphicsHolder = new GraphicsHolder(this);
JoystickView Joystick = new JoystickView(this);
// I need to set the Gravity HERE
Joystick.setLayoutParams(new RelativeLayout.MarginLayoutParams(500,500));
gameScreen.addView(mGraphicsHolder);
gameScreen.addView(Joystick);
setContentView(gameScreen);
}
}
Now Here's my Question: can you somehow set the Gravity of this View programmatically?
You can try this
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(500,500);
params.addRule(RelativeLayout.CENTER_IN_PARENT, RelativeLayout.TRUE);
Joystick.setLayoutParams(params);
Try to set gravity center to FrameLayout and use ViewGroup.LayoutParams set Joystick LayoutParams :
FrameLayout.LayoutParams params = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,FrameLayout.LayoutParams.MATCH_PARENT);
params.gravity = Gravity.CENTER;
gameScreen.setLayoutParams(params);
Joystick.setLayoutParams(new ViewGroup.LayoutParams(500,500));
try this.
FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) Joystick.getLayoutParams();
params.gravity = Gravity.TOP;// desired gravity
Joystick.setLayoutParams(params);
dont change ur code just add this after setContentView(gameScreen); hope it works
Well, I found the answer, but it's a completely different approach, since none of the above or those I found elsewhere worked for me.
I did the following changes in the onCreate method:
mGraphicsHolder = new GraphicsHolder(this);
LayoutInflater inflate = (LayoutInflater)
getSystemService(Context.LAYOUT_INFLATER_SERVICE);
setContentView(mGraphicsHolder);
getWindow().addContentView(inflate.inflate(
R.layout.controllayout, null), new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT,
ViewGroup.LayoutParams.FILL_PARENT));
Joystick = (JoystickView) getWindow().findViewById(R.id.joystickView1);
Joystick.setOnJostickMovedListener(this);
Now I got my Joystick on an XML Layout, but It actually works (at least in my case where nothing else worked), and it's quite easy to make changes in things of Layout etc.
I need to implement Dialog for my Android app through Java code, so I can't use XML.
I have root LinearLayout where I implement range seek bar, then I have another LinearLayout under root layout, with horizontal orientation, where I want to add two buttons in same row. So I need to set weight to 1, and width to FILL_PARENT and height to WRAP_CONTENT.
How I can do that with Java code?
LinearLayout.LayoutParams p = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
p.weight = 1;
rangeSeekBar.setLayoutParams(p);
I'm not sure which view you want to set the layout params on. I just assumed the rangeSeekbar to show an example. Change if you need.
When using the layout params always use the root's param type..
Ex. if you have a View you want to apply params to within a RelativeLayout use RelativeLayout.LayoutParams..
You can pass it in as part of the LinearLayout.LayoutParams constructor:
Did you mean wrap_content?
LayoutParams param = new LinearLayout.LayoutParams(
LayoutParams.MATCH_PARENT,
LayoutParams.WRAP_CONTENT, 1.0f);
1.0f is the weight
Is not using XML a requirement? If not, you could always build your layout in XML and then use a LayoutInflater at run-time to build up your view hierarchy and pass that to setView() on your dialog.
For example:
LayoutInflater inflater = LayoutInflater.from(getActivity());
View v = inflater.inflate(R.layout.my_dialog_layout, null);
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setView(v);
an easier way:
public static void setLayoutWeight(View view , float weight)
{
((LinearLayout.LayoutParams) view.getLayoutParams()).weight = weight;
view.requestLayout();
}
I am currently doing an android application that contains customize alert dialog. It contains a button , but i can't set the margin for the button . the code is given below. setmargin method is not working
AlertDialog.Builder myDialog = new AlertDialog.Builder(Login.this);
Button button = new Button(Login.this);
button.setText("Send");
LayoutParams buttonLayoutParams
= new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
button.setLayoutParams(buttonLayoutParams);
resetPassword=editText.getText().toString();
LinearLayout layout = new LinearLayout(Login.this);
layout.setOrientation(LinearLayout.VERTICAL);
layout.addView(textView);
layout.addView(editText);
layout.addView(button);
myDialog.setView(layout);
Write below code to set margin, it may help you.
AlertDialog.Builder myDialog = new AlertDialog.Builder(Login.this);
Button button = new Button(Login.this);
EditText editText = new EditText(Login.this);
TextView textView = new TextView(Login.this);
button.setText("Send");
LinearLayout.LayoutParams buttonLayoutParams = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
buttonLayoutParams.setMargins(50, 10, 0, 0);
button.setLayoutParams(buttonLayoutParams);
String resetPassword = editText.getText().toString();
LinearLayout layout = new LinearLayout(Login.this);
layout.setOrientation(LinearLayout.VERTICAL);
layout.addView(textView);
layout.addView(editText);
layout.addView(button);
myDialog.setView(layout);
myDialog.show();
Use LinearLayout.LayoutParams or RelativeLayout.LayoutParams according to parent layout of the child view
Just sharing a slightly different approach.
Instead of casting to LinearLayout.LayoutParams, RelativeLayout.LayoutParams, etc, you can just cast to MarginLayoutParams.
Casting to MarginLayoutParams is better because you can later update your layout and you don't need to return to your java code to change from LinearLayout to RelativeLayout or any other Layout type
You can do something like:
MarginLayoutParams layoutParams = (MarginLayoutParams) view.getLayoutParams();
// Set bottom margin
layoutParams.bottomMargin = x;
// Set top margin
layoutParams.topMargin = x;
// Set left margin
// This won't have effect if you set any relative margin (start) previously or in the layout.xml
layoutParams.leftMargin = x;
// Set left margin
// This won't have effect if you set any relative margin (end) previously or in the layout.xml
layoutParams.rightMargin = x;
// Set start margin
layoutParams.setMarginStart(x);
// Set end margin
layoutParams.setMarginStart(x);
// Set all left, top, right, bottom margins at once
// Note that here, left and right margins are set (not start/end).
// So, if you have used start/end margin before (or via layout.xml),
// setting left/right here won't have any effect.
layoutParams.setMargins(left, top, end, bottom)
// Then re-apply the layout params again to force the view to be re-draw
// This step may not be necessary because depending where you set the margin,
// view is already scheduled to be drawn
// For any case, to ensure the view will apply the new margin, call:
view.setLayoutParams(layoutParams);
buttonLayoutParams.bottomMargin
buttonLayoutParams.topMargin
buttonLayoutParams.leftMargin
buttonLayoutParams.rightMargin
can be used to set margins
The setMargin() method is available if you're using LinearLayout.LayoutParams but not if you're using ViewGroup.LayoutParams. Dipak Keshariya alludes to this but doesn't say it in so many words.
You can set in LinearLayout margin
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
LinearLayout.LayoutParams layoutParams = new
LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
layoutParams.setMargins(30, 20, 30, 0);
Button okButton=new Button(this);
okButton.setText("some text");
ll.addView(okButton, layoutParams);
This works for me (The support library (need to use AndroidX):
Kotlin
val params = LinearLayoutCompat.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT
).apply {
setMargins(0,16,0,16)
}
Java
LinearLayoutCompat.LayoutParams params = LinearLayoutCompat.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT
)
params.setMargins(0,16,0,16)
I created LinearLayout and Button via class not via XML. I know how to inflate layout view and button view dont know how to set margins of them. I need to set margins of my button and my linearlayout. If I use XML, it is very simple: <android:marginLeft="10px">.
But, what should I do if I want to set margin by class not by XML?
In this we have linear layout in main.xml named lyt1 and we add edittext at runtime and set
left margin value
please use bleow code :
lyt = (LinearLayout)findViewById(R.id.lyt1);
EditText txt = new EditText(WvActivity.this);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT);
lp.leftMargin = 10;
txt.setLayoutParams(lp);
lyt.addView(txt);
lyt.invalidate();
Use:
LinearLayout.LayoutParams params=new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
params.setMargins(left, top, right, bottom);