How do I set android:layout_columnWeight=“1” programmatically to an element in an android support v7 Gridlayout

问题

I'm trying to build a GirdLayout programmatically with 2 columns and I want these columns to have equal width set at half the width of the screen.

I figured out you can do this since API 21 or with the support v7 GirdLayout view. I see examples that uses android:layout_columnWeight="1" to do this. But I can not find how to do this programmatically.

Can anyone help me with this matter?

package com.tunify.v3.component;

import java.util.ArrayList;

import android.support.v7.widget.GridLayout;
import android.util.DisplayMetrics;
import android.util.TypedValue;
import android.view.ViewGroup;

import com.tunify.asme.data.ChangeableSelectionParameterValue;

public class ChangeableSelectionParameters extends GridLayout{

//private ArrayList<ChangeableSelectionParameterView> selectionParameterViews;
private ArrayList<ChangeableSelectionParameterValue> selectionParameterValues;

private static final int ITEM_PADDING_LEFT_DP = 0;
private static final int ITEM_PADDING_RIGHT_DP = 0;
private static final int ITEM_PADDING_TOP_DP = 0;
private static final int ITEM_PADDING_BOTTOM_DP = 0;

//private static final int MUSICCOLLECTION_DISPLAY_TEXT_SIZE_SP = 15;


public ChangeableSelectionParameters(android.content.Context context, ArrayList<ChangeableSelectionParameterValue> selectionParameterValues) {
    super(context);

    this.selectionParameterValues = selectionParameterValues;

    initializeLayoutBasics(context);
    initializeComponents();
}

private void initializeLayoutBasics(android.content.Context context) {
    setOrientation(VERTICAL);
    setColumnCount(2);
    setRowCount((int)Math.ceil(selectionParameterValues.size()/2.0));

    int width = ViewGroup.LayoutParams.MATCH_PARENT;
    int height = ViewGroup.LayoutParams.WRAP_CONTENT;
    android.view.ViewGroup.LayoutParams layoutParams = new android.view.ViewGroup.LayoutParams(width, height);
    this.setLayoutParams(layoutParams);

    DisplayMetrics metrics = getResources().getDisplayMetrics();

    int paddingLeftPx = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, ITEM_PADDING_LEFT_DP, metrics);
    int paddingRightPx = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, ITEM_PADDING_RIGHT_DP, metrics);
    int paddingTopPx = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, ITEM_PADDING_TOP_DP, metrics);
    int paddingBottomPx = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, ITEM_PADDING_BOTTOM_DP, metrics);
    setPadding(paddingLeftPx, paddingTopPx, paddingRightPx, paddingBottomPx);

}

private void initializeComponents() {

    for(ChangeableSelectionParameterValue param : this.selectionParameterValues){
        ChangeableSelectionParameterView v = new ChangeableSelectionParameterView(getContext(), param);
        //TODO set views layout column weight to 1
        this.addView(v);
    }
 }
}

SOLUTION:

 GridLayout.LayoutParams parem = new LayoutParams(GridLayout.spec(GridLayout.UNDEFINED, 1f),      GridLayout.spec(GridLayout.UNDEFINED, 1f));
 v.setLayoutParams(parem);

回答1:

I found this method from GridLayout: http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/5.0.0_r1/android/widget/GridLayout.java#GridLayout.spec%28int%2Cfloat%29

So maybe you could try something like this:

((GridLayout.LayoutParams) this.getLayoutParams()).columnSpec =
    GridLayout.spec(GridLayout.UNDEFINED, 1f);

回答2:

-Here you are ! :>

Button button = new Button(this);
GridLayout.LayoutParams param= new GridLayout.LayoutParams(GridLayout.spec(
            GridLayout.UNDEFINED,GridLayout.FILL,1f),
            GridLayout.spec(GridLayout.UNDEFINED,GridLayout.FILL,1f));
param.height = 0;                                                                                                           
param.width = 0;
button.setLayoutParams(param);

回答3:

This functions of GridLayout.Spec will allow you to set the weight correctly:

public static Spec spec(int start, int size, Alignment alignment, float weight)
public static Spec spec(int start, Alignment alignment, float weight)
public static Spec spec(int start, int size, float weight) 
public static Spec spec(int start, float weight)

usage example:

((LayoutParams) gm.getViewFromGridCoords(i, j).getLayoutParams()).columnSpec = GridLayout.spec(j, span, CENTER, 1);

回答4:

For anyone using xamarin.android, these answers helped me, but I had to change the syntax a bit. So if anyone else is using xamarin.android here is the syntax:

GridLayout.LayoutParams param = new GridLayout.LayoutParams();
param.RowSpec = GridLayout.InvokeSpec(GridLayout.Undefined, 1f);
param.ColumnSpec = GridLayout.InvokeSpec(GridLayout.Undefined, 1f);
view.LayoutParameters = param;

Where view is the view contained in the GridLayout.

来源：https://stackoverflow.com/questions/31655352/how-do-i-set-androidlayout-columnweight-1-programmatically-to-an-element-in-a