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You can set a LinearLayout to the top left of a screen by doing this:

  android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"

I was wondering how would I do this programmatically?

I have the following piece of code:

 LinearLayout btnBar = (LinearLayout) findViewById(R.id.btnBar);
    LinearLayout.LayoutParams btnBarParams = new LinearLayout.LayoutParams(screenWidth,screenHeight / 3);
 //Not sure how to set the layout to the top left.

but in LayoutParameters there is no addRule() method so I am not sure how to set these attributes. The LinearLayout is inside a RelativeLayout.

EDIT: I think I figured it out, but I am getting a exception. Here is my solution:

   LinearLayout btnBar = (LinearLayout) findViewById(R.id.btnBar);
    LinearLayout.LayoutParams btnBarParams = new LinearLayout.LayoutParams(screenWidth,screenHeight / 3);
    btnBarParams.gravity = Gravity.START;
    btnBar.setLayoutParams(btnBarParams);

But I cannot see if this is working because I get a exception on the last line of my solution saying

java.lang.ClassCastException: android.widget.LinearLayout$LayoutParams cannot be cast to android.widget.RelativeLayout$LayoutParams

Foobar
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2 Answers2

1

The solution turned out to be using RelativeLayout.LayoutParams

 LinearLayout btnBar = (LinearLayout) findViewById(R.id.btnBar);
    RelativeLayout.LayoutParams btnBarParams = new RelativeLayout.LayoutParams(screenWidth,screenHeight / 3);
    btnBarParams.addRule(RelativeLayout.ALIGN_PARENT_TOP);
    btnBarParams.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
    btnBar.setLayoutParams(btnBarParams);
Foobar
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This is how it will work, 

LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.FILL_PARENT);
params.weight = 1.0f;
params.gravity = Gravity.TOP;

btnBar.setLayoutParams(params);
User0911
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